Journal Logo

COVID

Evidence of SARS-CoV-2 Infection in Cells, Tissues, and Organs and the Risk of Transmission Through Transplantation

Gaussen, Amaury PhD1; Hornby, Laura MSc2,3; Rockl, Gary MSc1; O’Brien, Sheila PhD3; Delage, Gilles MD4; Sapir-Pichhadze, Ruth MD, PhD5,6,7; Drews, Steven J. PhD8,9; Weiss, Matthew J. MD10,11,12; Lewin, Antoine PhD4,13

Author Information
doi: 10.1097/TP.0000000000003744

Abstract

INTRODUCTION

Since the first cases of infection were reported on December 31, 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide. Human-to-human viral transmission is the predominant mechanism, mainly upon contact with droplets of respiratory secretions from an infectious individual, which can occasionally include aerosol transmission. The virus was initially isolated from bronchoalveolar lavage (BAL) fluids of symptomatic patients, but several signs and symptoms of coronavirus disease 2019 (COVID-19) revealed the possible involvement of organs other than the lungs. These findings have raised concerns about the potential for direct infection of different kinds of cells, tissues, and organs (CTO) throughout the body. Damage to organs has been documented in COVID-19 patients, but it is unclear at this time if this is attributable to direct damage caused by SARS-CoV-2 infection or rather, medications, preexisting conditions, or immune/inflammatory responses.

This uncertainty regarding the potential route of CTO infection has created tremendous pressures on the organ and tissue donation and transplantation communities. A safe supply of CTO is a prerequisite and all efforts are made to prevent transmission of infectious diseases.1,2 In the pandemic context due to a novel infectious agent, there is widespread concern that the transplantation of CTO from an unknown and undetected COVID-19 positive donor may lead to infection in the recipient. This is particularly important since there is a possibility of worse clinical outcomes for solid organ recipients following community or hospital-acquired COVID-19 infections in comparison to matched controls, but this still has to be elucidated.3-5 The risk of COVID-19 transmission must be weighed against the risks of withholding transplantation,6 which occurred in several jurisdictions during the spring of 2020.7 At the beginning of the pandemic, there was uncertainty about the risk of nosocomial infection for procurement and transplant teams, as well as for recipients. In addition, the healthcare system faced limited hospital resources and intensive care unit beds. These factors, among others, impacted capacity to maintain transplant activity.

SARS-CoV-2 has been isolated from the respiratory tract until day 9 since symptom onset (SSO), despite the detection of high viral RNA loads subsequently. Also, a recent analysis of severe and critical COVID-19 patients revealed a median duration of infectious viral shedding 8 d SSO, with 1 case of SARS-CoV-2 isolation until day 20 SSO.8-13 SARS-CoV-2 viral load in lower and upper respiratory tract has been shown to peak within the 1–2 wk SSO, with a mean duration of shedding until days 15th and 17th, respectively.8 These results concur with previous observations from other respiratory viruses of detectable viral RNA by sensitive molecular techniques beyond infectivity.14,15 Since asymptomatic yet infectious patients could present as potential donors, clinical evaluation alone will not entirely mitigate the risk of possible transmission. Currently, there is evidence of COVID-19 to suggest asymptomatic infection in adults16-21 and children,20,22-24 but the incidence and prevalence of asymptomatic cases are not clearly established.

Thus, screening is critical to rule out infection, but the sensitivity of reverse transcription-polymerase chain reaction (RT-PCR) has been challenged based on the adequate collection of samples, the type of sample and the quality of the RT-PCR assays.25-27 A low viral load early in the infection course may make the detection of SARS-CoV-2 RNA difficult. The probability of obtaining a false-negative RT-PCR result before symptom onset ranges between 100% on day 1 postexposure to SARS-CoV-2 to 67% on day 4 postexposure, considering a median incubation period of 5 d.28 False-negative results can have serious implications for public health, and even more so when screening of CTO donors, given the risk of proceeding to transplantation from a donor with an undetected infection.

Some groups have attempted to estimate the risk of bloodborne transmission of SARS-CoV-2.29 Blood banks have adapted their collection practices to screen potential donors for COVID-19 symptoms or close contacts with known COVID-19.30 Tracking protocols have also been implemented to identify blood products from donors who develop COVID-19 disease postdonation.31 To date, no transfusion acquired COVID-19 has been reported, even when transfusions occurred with donations from presymptomatic or asymptomatic donors.31-34 Moreover, SARS-CoV-2 has not been isolated from the blood of confirmed COVID-19 patients and neither have been other coronaviruses.9,35,36 In contrast, SARS-CoV-2 RNA has been detected in whole blood and plasma of mostly symptomatic but also asymptomatic people and donors.29 Even in studies reporting on the virus being identified in members of their cohort found it only in a few cases, suggesting that most COVID-19 patients do not present with viral genomic material in their blood.37-39 When SARS-CoV-2 RNA was detected in the blood, it was found at extremely low levels as demonstrated by cycle threshold (CT) values of RT-PCR amplification >30, which are close to the cutoff value of accurate positive results, increasing the probability of false positives. These elements, in addition to the fact that hematogenous transmission has not been reported to date, have led researchers to conclude that the risk of transmission by blood transfusion should be considered solely theoretical.29 It is possible, however, that SARS-CoV-2 RNA detection in blood is related to the dissemination of RNA fragments in the circulation rather than low level of infectious particles.

Although reassuring, the lack of documented transmission from blood products does not preclude transmission through transplantation of solid organs, tissues, or hematopoietic stem cells (HSCs). In the context of organ transplantation, very low levels of infectious SARS-CoV-2 particles in the blood could affect other organs, giving rise to sustained viral replication in the presence of cellular entry factors. The purpose of this review is to explore the current state of knowledge on the risk of transmission of virulent SARS-CoV-2 through transplantation. To evaluate this risk, we first identified biologic evidence supporting the possibility of a potential infection of various cell and tissue types. We then reviewed the reports of SARS-CoV-2 detection in CTO, including autopsy studies. Finally, we conducted an extensive search until January 2021 to identify cases of CTO transplantation from COVID-19 positive donors to recipients. A full description of the PICO questions, search methods, sources, and results, is provided in File S1: Materials and Methods, SDC, http://links.lww.com/TP/C182.

CELL TYPE SUSCEPTIBILITY TO INFECTION

Molecular analysis and cellular level in vitro experiments have demonstrated that SARS-CoV-2 virus, as the prior severe acute respiratory syndrome coronavirus (SARS-CoV),40 uses angiotensin-converting enzyme 2 (ACE2) as a receptor, and that transmembrane serine protease 2 (TMPRSS2) is able to prime SARS-CoV-2 spike protein for cell entry.41,42 Emerging results also suggest that furin could play a role in cellular entry of the virus.43 SARS tropism for ACE2 positive cells in several tissues and organs suggested that SARS-CoV-2 could also have extrapulmonary targets like kidney and the gastrointestinal tract.44-46 Moreover, the binding affinity of SARS-CoV-2 ectodomain for ACE2 appears to be 10- to 20-fold higher than SARS-spike protein affinity for this receptor.47 Although SARS-CoV-2 could bind to other receptors, as suggested by some studies, and the spike protein cleaved by other proteases (furin is a potential candidate), human cells expressing ACE2 and TMPRSS2 are potential biologic targets of this virus. However, the presence of these molecules in higher quantity on human cell membranes does not alone constitute enough evidence to predict pathologic organ infection.

Cell culture models have been used to screen differences in susceptibility to SARS-CoV-2 infection and replication as well as cytopathic effects.44 While displaying potential physiologic differences from in vivo organisms, immortalized cell lines have been used to study Middle East respiratory syndrome coronavirus virus tropism and replication with good correspondence between cell lines and patients.48 Biologic differences between cancer cell lines and primary cells have led to the study of other models like cells and organoids derived from human stem cells,49,50 but human pluripotent stem cells (hPSCs) infectivity has yet to be compared with adult cells.

Analysis of gene expression of virus receptors from different nonpathologic human tissues identified ACE2 expression in colon colonocytes, ileum and rectum endothelial cells, and kidney proximal tubules.51 Other large genomic data sets from normal tissues and cells indicate that ACE2 gene is expressed in the intestinal tract, and particularly by ileal enterocytes as revealed by single-cell RNA sequencing, as well as in duodenum and small intestine, as detected by immunohistochemical analysis.52,53 In vitro experiments by Chu et al with different human cell lines showed that SARS-CoV-2 infects and replicates at the same level in intestinal Caco2 cells as in pulmonary Calu3 cells, but cytopathic effects were only observed in nonhuman primate cell lines (VeroE6 and FRhK4) beyond 24 h and up to 120 h inoculation period.54 Data sets generated by single-cell RNA sequencing from human noninfected tissue samples and animal samples were used by Ziegler et al to identify pulmonary type II pneumocytes, ileal absorbent enterocytes, and secretory goblet cells of the nose as ACE2 and TMPRSS2 gene expressing cells.55 Human intestinal organoids generated from small and large mucosa cells have been used as a model to recapitulate biologic processes of the digestive tract as a source of all progenitor and differentiated cell types of the intestinal epithelium.56,57 Human small intestinal organoids (hSIO) were cultured under different conditions to represent a variability in cell nature and proportion and were then inoculated with SARS-CoV-2 subsequently demonstrating infection as well as a viral replication.56,57 This was demonstrated by reverse transcription-quantitative PCR (qRT-PCR) and viral titration on Vero E6 cells that resulted in increased quantities of RNA and virus progeny.57 Immunostaining and microscopy analysis also showed that enterocytes can be infected by SARS-CoV-2 in hSIO cultivated in proliferating and differentiation conditions. Zhou et al also demonstrated the expression of both ACE2 and TMPRSS2 gene transcripts in hSIO.

The susceptibility of liver tissue to SARS-CoV-2 infection is of great interest. To date, gene and protein expression analysis from public data sets have shown the presence of ACE2 in liver cholangiocytes and gallbladder51-53 and, in in vitro experiments, SARS-CoV-2 demonstrated the ability to infect and replicate in hepatic Huh754, primary human hepatocytes, and cholangiocytes organoids.49,50 Moreover, a reduction in gene expression essential for bile acid transport and tight junctions between cholangiocytes was observed following infection of human liver ductal organoids suggesting a possible negative impact of SARS-CoV-2 infection on hepatic tissue structure and function.50

In the pancreas, ACE2 and TMPRSS2 transcripts have been found in alpha cells and beta cells of primary islets49,58,59 and the ACE2 protein expression has been visualized by immunostaining in small capillaries of the pancreas,52 in alpha and in beta cells.49 SARS-CoV-2 pseudovirus demonstrated infection of pancreatic endocrine cells derived from hPSCs, and SARS-CoV-2 virus was able to infect adult human primary islets in vitro.49

Transcripts of ACE2 genes and ACE2 protein were detected in kidney cells, with mRNA expression localized to renal proximal tubules.51,52 Mass spectrometry and protein abundance data indicate ACE2 is abundantly present in the kidney.52,53 ACE2 expression was also identified in cell clusters from kidney organoids generated from human embryonic stem cells.60 SARS-CoV-2 was able to infect and replicate into renal 293T cells54 and kidney organoids, producing infectious viral progeny, proven by infecting Vero E6 cells with supernatant from infected organoids and detecting consecutively increased level of SARS-CoV-2 RNA by qRT-PCR.60

The ACE2 gene is also expressed in heart cells,52 in cardiomyocytes and pericytes.61,62 Immunostaining has detected ACE2 protein expression in small capillaries and cardiomyocytes.52 hPSC-derived cardiomyocytes express ACE2 as revealed by immunostaining, and these cells demonstrated susceptibility to infection by SARS-CoV-2 pseudovirus.49

Human capillary organoids generated from induced pluripotent stem cells were successfully used as a model to show that SARS-CoV-2 is capable of infection and replication.60 In this report, supernatant from infected capillary organoids was also able to infect Vero E6 cells, again demonstrating the infectiousness of viral progeny.

ACE2 and TMPRSS2 genes expression has been detected in both conjunctiva and cornea of normal human samples,63,64 while ACE2 and TMPRSS2 genes were only identified in the conjunctival and pterygium cells from some patients.65 ACE2 protein has been detected by immunostaining in superficial layers of conjunctiva and cornea, as well as TMPRSS2.52,66,67 Ex vivo cultures of human nontumor conjunctiva can be infected by SARS-CoV-2 as infectious viral titers in tissue culture supernatant demonstrates consistent replication and immunostaining reveals the presence of viral nucleoproteins in explants.68

Single-cell ACE2 gene expression analysis showed no ACE2 transcripts in bone marrow containing immune cells, mesenchymal stem cells, progenitor cells, and blood cells.51,52 These results are consistent with proteomics results interpreted from other data sets.53 In pseudovirus infectivity assay, macrophages demonstrated low susceptibility to SARS-CoV-2.49

VIRAL DETECTION

An extensive search strategy led to the identification of 38 references reporting in vitro and postmortem detection of SARS-CoV-2 in cells and tissues (Table 1). RT-PCR demonstrates a very high sensitivity for detecting viral RNA. However, the interpretation of RT-PCR analysis must be made with caution since a positive result may indicate a qualitative and quantitative detection of genomic material without consideration of its origin nor its ability to infect cells and replicate in vivo. The RNA fragments amplified by RT-PCR can be undergoing a postviral clearance process or be a sign of the presence of infectious virus. In respiratory specimens, an association has been made between CT values and infectivity, with a short time to symptoms onset and low CT values associated with an increased possibility of collecting infectious specimens from patients.10,11 However, high viral loads as measured by RT-PCR have also been measured in specimens from patients that could not demonstrate infection of cells in culture experiments, meaning that definite CT counts intervals alone cannot be considered reliably predictive of infectivity.9-11

TABLE 1. - In vitro and postmortem detection of SARS-CoV-2 in cells and tissues
Authors Organs/tissues investigated Type of study Patients and type of samples Tests and analysis Viral infectivity assays
Jeong et al Clinical specimens In vitro 5 COVID-19 patients in mild (n = 1), severe (n = 3), and critical condition (n = 1).Clinical specimens: naso/oropharyngeal swabs and saliva, urine, and stool samples. SARS-CoV-2 qRT-PCR: positive in all naso/oropharyngeal swabs (1.18 ± 0.12 to1.34 ± 0.30 log10 copies/mL), saliva (1.07 ± 0.34 to 1.65 ± 0.46 log10 copies/mL), urine (1.08 ± 0.16 to 2.09 ± 0.85 log10 copies/mL), and stool samples (1.17 ± 0.32 to 2.18 ± 0.11 log10 copies/mL) collected between d 8 and 30 postsymptoms onset. Positive virus isolation in Vero cells from 1 naso/oropharyngeal swab and 2 saliva specimens (from severe and critical COVID-19 patients).Positive virus isolation following inoculation of ferrets with 2 human urine samples (severe COVID-19) and 1 stool sample (critical COVID-19).
Kim et al Clinical specimens In vitro 74 COVID-19 positive patients.Collection of serum, urine and stool samples. SARS-CoV-2 RT-PCR: positive in serum samples of 6 patients; positive in urine samples of 2 patients; positive in stool samples of 8 patients. Negative virus isolation following Caco-2 cells inoculation by serum, urine or stool SARS-CoV-2 RT-PCR positive samples.
Wang et al Clinical specimens In vitro 205 COVID-19 positive patients, in severe and nonsevere condition. Collection of pharyngeal swabs, blood, sputum, feces, urine, and nasal samples.Bronchoalveolar lavage fluid and fibrobronchoscope brush biopsy were sampled from patients with severe illness. SARS-CoV-2 rRT-PCR: 14 of 15 (93%) positive bronchoalveolar lavage fluid specimens; 72 of 104 (72%) positive sputum specimens; 5 of 8 (63%) positive nasal swabs; 6 of 13 (46%) positive fibrobronchoscope brush biopsy; 126 of 398 (32%) pharyngeal swabs; 44 of 153 (29%) positive feces specimen; 3 of 307 (1%) positive blood samples.None of the 72 urine specimens tested positive. Culture of cells with 4 SARS-CoV-2 positive fecal specimens with high copy numbers.Live SARS-CoV-2 isolated from 2 patients stool samples (data not shown).
Wölfel et al Clinical specimens In vitro 9 COVID-19 positive patients with mild course.Collection of sputum and nasopharyngeal swabs, stool, serum and urine samples. SARS-CoV-2 RT-PCR: Positive in oro- and naso-pharyngeal swabs in all patients.Positive in stool samples of 8 patients. Negative in urine samples collected from all 9 patients. Negative in serum samples collected from all 9 patients. Isolation of infectious virus from throat- and lung-derived samples. Active replication of SARS-CoV-2 in throat samples by identification of viral subgenomic messenger RNAs (sgRNA).No or very low viral replication in stool samples by identification of sgRNA.Unsuccessful viral isolation from stool samples.
Xiao et al Clinical specimens Biopsy 1 COVID-19 positive patient who died ultimately. SARS-CoV-2 RT-PCR: positive in stool specimens. Inoculation of Vero E6 cells with fecal specimen.Cytopathic effect observed. Viral-like particles detected by transmission electron microscopy in culture supernatant.
Zhou et al Clinical specimens In vitro 1 COVID-19 positive patient with diarrhea. SARS-CoV-2 qRT-PCR: positive in stool specimen (CT value of 33.6). Positive isolation of infectious virus from the stool specimen (data not provided).
Arora et al Eye In vitro 75 SARS-CoV-2 RT-PCR positive patients with moderate and severe symptoms.Collection of tears from both the eyes. RT-PCR: positive in tears of 18 patients. Absence of ocular signs and symptoms. ND
Atum et al Eye In vitro 40 SARS-CoV-2 RT-PCR positive patients.Collection of conjunctival swabs. rRT-PCR on conjunctival swabs: 3 positive patients.Signs and symptoms: 10 patients diagnosed with conjunctivitis. Only 1 of them was found positive by conjunctival swab rRT-PCR. ND
Bayyoud et al Eye Postmortem 1 COVID-19 deceased patient. Collection of conjunctival fluid swabs, bulbar conjunctiva, corneal epithelium, corneal stroma, corneal endothelium, anterior chamber fluid, lens, iris, vitreous, retina, uvea, sclera and optic nerve. qRT-PCR: no SARS-CoV-2 RNA was detected in the samples collected. ND
Chen et al Eye Signs and symptoms 535 COVID-19 positive patients with mild symptoms. Signs and symptoms: 27 patients manifested conjunctival congestion (4 as the initial symptom). ND
Colavita et al Eye In vitro 1 COVID-19 positive patient with bilateral conjunctivitis.
Collection of ocular swabs.
RT-PCR: positive for SARS-CoV-2 on ocular swabs from d 3 to 21 posthospital admission (d 3: CT, 21.6).CT values detected in the late ocular samples were lower than those observed in the nasal swabs. Confirmed.Cytopathic effect observed 5 d postinoculation on Vero E6 cells.
Viral replication confirmed by real-time RT-PCR.
Seah et al Eye In vitro 17 COVID-19 positive patients.
Collection of tears samples.
RT-PCR: all samples showed negative results for SARS-CoV-2. Unsuccessful SARS-CoV-2 isolation.No cytopathic effects observed on Vero E6.
Valent et al Eye In vitro signs and symptoms 27 pediatric COVID-19 positive patients.Collection of conjunctival swabs. Signs and symptoms: ocular manifestations observed in all patients at admission.RT-PCR: 1 symptomatic and 2 asymptomatics for ocular infection, were positive for SARS-CoV-2 at first conjunctival swab; 2 became negatives on the second test and 1 on the third. ND
Wu et al Eye In vitro signs and symptoms 38 clinically confirmed COVID-19 positive patients. 28 SARS-CoV-2 RT-PCR positive patients with mild, moderate, severe, and critical COVID-19.Collection of conjunctival swabs. Ocular manifestations consistent with conjunctivitis observed for 12 patients (31.6%).2 positive patients among 28 RT-PCR positive COVID-19 patients tested on nasopharyngeal swabs. ND
Xia et al Eye In vitro signs and symptoms 9 severe and 21 nonsevere COVID-19 positive patients.Collection of tears and conjunctival secretions. RT-PCR positive for the 2 samples of tear and conjunctival secretions obtained from the patient with conjunctivitis.58 samples from other patients were all negative. Unsuccessful
Bayyoud et al Eye Postmortem 5 COVID-19 positive patients deceased of respiratory insufficiency.Collection of 10 bulbi.Collection of corneal stroma and endothelium, bulbar conjunctiva, conjunctival fluid swabs, anterior chamber fluid and corneal epithelium. qRT-PCRs: no viral RNA in corneal stroma and endothelium, bulbar-limbal conjunctiva, conjunctival fluid swabs, anterior chamber fluid, and corneal epithelium. ND
Lindner et al Heart Postmortem 39 patients deceased from COVID-19 (16 males and median age of 85 y).Collection of cardiac tissue samples. SARS-CoV-2 RT-PCR in myocardium: positive for 24 of 39 patients. Viral load >1000 copies per μg RNA in 16 of 39 patients.In situ hybridization: localization of SARS-CoV-2 RNA in interstitial cells in myocardium tissue.No diagnosis of myocarditis. Viral replication determined by cDNA synthesis: positive in the 5 patients with the highest viral load.
Tavazzi et al Heart Postmortem 1 COVID-19 positive patient deceased of bacterial septic shock.
Endomyocardial biopsy.
Light and electron microscopy: viral-like particles in interstitial cytopathic macrophages and their surroundings. No observation of viral-like particles in cardiac myocytes.Histopathological examinations: nonspecific damages in cardiomyocytes; neither cytopathic endothelia, small intramural vessel inflammation, or thrombosis. ND
Braun et al Kidney Postmortem 63 COVID-19 positive patients. SARS-CoV-2 RT-PCR: positive in kidney tissues in 60% (38 of 63) of patients. Inoculation of Vero cells with kidney tissues homogenate. Viral load increase detected by RT-PCR from cell culture supernatants. SARS-CoV-2 nonstructural protein 3 detected by immunostaining in Vero cells.
Diao et al Kidney Postmortem Medical records of 85 COVID-19 positive patients.Autopsies conducted for 6 COVID-19 positive patients.Collection of kidney tissues. Signs-symptoms: 3 of 85 patients exhibited acute renal failure.Electron microscopy: virus-like particles observed in the kidneys.Immunohistochemistry: observation of SARS-CoV-2 nucleocapsid protein antigen accumulation in kidney tubules.
H&E staining: severe acute tubular necrosis and lymphocyte infiltration.
ND
Roufosse et al Kidney Biopsy Live patients with COVID-19. Collection of kidney tissue. Electron microscopy: no observation of SARS-CoV-2 viral particles. ND
Su et al Kidney Postmortem 26 patients deceased from COVID-19 (respiratory failure and multiple organ dysfunction syndrome).19 male and 7 females (average of 69 y). Light microscopy: kidney tissue injury. Electron microscopic examination: coronavirus-like particles in the tubular epithelium and podocytes.Immunostaining with SARS-CoV nucleoprotein antibody: positive in tubules.Histopathological examination: diffuse proximal tubule injury. ND
Frelih et al Kidney lungs Postmortem 4 COVID-19 positive deceased patients.Collection of lung and kidney specimens. SARS-CoV-2 RT-PCR: positive in all lung samples. Negative in all kidney samples.Transmission electron microscopy: intracellular vesicular structures observed in lung and kidney specimens.No observation of viral infection of organs. ND
Remmelink et al Kidney, lungs, heart, liver, spleen, colon, brain, bone marrow Postmortem complete autopsies 17 patients deceased from COVID-19.Complete sets of tissue samples collected. SARS-CoV-2 RT-PCR: positive in at least 1 organ from every patient; positive in all tested organs from 8 patients.CT values for nonpulmonary organs: from 28.67 to 35.11.Immunohistochemistry on lung samples: positive cells with a heterogeneous distribution (11 of 17 patients).Histopathological examinations: diffuse alveolar damage on 15 of 17 patients; microthrombi in small lung arteries on 11 patients.No evidence of myocarditis, hepatitis, or encephalitis. No specific viral organ injury. ND
Puelles et al Kidney, lungs, pharynx, heart, liver, brain Postmortem 27 COVID-19 positive patients in which 22 patients deceased from COVID-19.More than 2 coexisting conditions on 17 patients.Kidney tissue microdissection in additional 5 COVID-19 patients. SARS-CoV-2 qRT-PCR: high viral load detected in the respiratory tract. Lower viral load detected in the kidneys, liver, heart, brain, and blood.Kidney tissue microdissections: SARS-CoV-2 viral load detectable on all kidney compartments examined.In situ hybridization and indirect immunofluorescence with confocal microscopy: detection of SARS-CoV-2 RNA and spike proteins in kidney. ND
Beigmohammadi et al Lungs, heart, and liver Postmortem core needle biopsies 7 patients deceased from COVID-19. Histopathological examinations: lung: diffuse alveolar damage and other alterations; liver: nonspecific findings; heart: no myocarditis observed. ND
Varga et al Lungs, heart, kidney, intestine Postmortem analysis and living biopsy analysis 3 COVID-19 positive patients with preexisting conditions (developed respiratory failure). 2 males.Postmortem analysis on 2 patients: 1 patient survived and biopsy was performed on the small intestine. Electron microscopy: observation of viral-like inclusion structures in endothelial cells for 1 patient.Histopathological examinations: observation endothelial cell involvement.Observation of viral-like elements within endothelial cells, accumulation of inflammatory cells, and evidences of endothelial and inflammatory cell death.No sign of lymphocytic myocarditis in patient 2. ND
Schaller et al Lungs, heart, liver, spleen, kidney, brain, pleural effusion, and cerebrospinal fluid Postmortem 10 COVID-19 positive deceased patients. Average of 79 y (range, 64–90 y). 7 males. Median of 4 known preexisting comorbidities (cardiovascular disease being most frequent). Preexisting structural lung damage found on 2 patients.Collection of postmortem nasopharyngeal, tracheal, and bronchial swabs. Collection of pleural effusion and CSF. RT-PCR: SARS-CoV-2 detected in the respiratory tracts of all patients, in pleural effusion but negative in all CSF samples.Histopathological examinations: lungs: diffuse alveolar damage, patchy lymphocyte infiltration, and other alterations; liver: unspecific inflammation; heart: mild lymphocytic myocarditis and signs of epicarditis on some cases.No direct viral organ infection evidence. ND
Tian et al Lungs, liver, and heart Postmortem 4 patients deceased from COVID-19. Three males and 1 female (59–81 y old).At least 1 underlying disease. Needle core biopsies of lung, liver, and heart. Histological examinations: lungs: diffuse alveolar damage; intra-alveolar neutrophilic infiltration. Liver: mild lobular infiltration by small lymphocytes and centrilobular sinusoidal dilation. Patchy necrosis. Heat: changes likely secondary or related to the underlying diseases. ND
Xu et al Lungs, liver, and heart tissue Postmortem analysis Patient who died from severe infection with SARS-CoV-2.Biopsies from lung, liver, and heart tissue. Histological examinations: lungs: no obvious intranuclear or intracytoplasmic viral inclusions; liver: moderate microvesicular steatosis and mild lobular and portal activity but no conclusive evidence to support SARS-CoV-2 infection; heart: few interstitial mononuclear inflammatory infiltrates and no other substantial damage. ND
Yao et al Lungs, liver, heart, intestine, skin, bone marrow Postmortem analysis COVID-19 positive patient who died from sudden cardiovascular accident. SARS-CoV-2 digital PCR on tissue sections: positive only in the lung. Negative for other tissues.Electron microscopic: coronavirus-like particles observed in bronchiolar epithelial cells and type II alveolar epithelial cells. Immunohistochemical staining targeting SARS-CoV-2 nucleocapsid: signal detected in the lung tissue.Histopathological examinations: lung tissue: diffuse alveolar damage; infiltrated immune cells in alveolar space and septa.SARS-CoV-2 not detected in the liver, heart, intestine, skin, and bone marrow. ND
Martines et al Lungs, liver, kidney, heart, intestine, spleen Postmortem analysis 8 patients deceased from COVID-19.Respiratory viral or bacterial coinfections were identified in 6 cases. Electron microscopy: virus-like particle observed in conducting airways and in the lungs. Immunohistochemistry: SARS-CoV-2 localization in upper airways, pneumocytes, alveolar macrophages and a hilar lymph node. No evidences of SARS-CoV-2 localization in other tissues.Histopathological examinations: no definitive viral inclusions observed; Lung: diffuse alveolar damage; No myocarditis or myocardial necrosis; Intestine: no notable changes.SARS-CoV-2 RT-PCR positive in the lungs and respiratory airways. ND
Barton et al Multiple organs Complete autopsies 2 COVID-19 positive patients 1- to 77-y-old obese man with medical history.2- to 42-y-old obese man with medical history. 1-SARS-CoV-2 positive on postmortem nasopharyngeal and lung parenchymal swabs.2- SARS-CoV-2 positive on postmortem nasopharyngeal swab and negative on lung parenchymal swabs.Histopathological examinations: neither autopsy revealed viral inclusions, mucus plugging in airways, eosinophils or myocarditis. ND
Menter et al Multiple organs Postmortem analysis 21 COVID-19 positive patients deceased from respiratory failure. Preexisting comorbidities in most patients. Histopathological examinations: Lungs: diffuse alveolar damage. Generalized thrombotic microangiopathy observed on 3 patients. Other organ damages not attributed to viral infection. ND
Hanley et al Multiple organs Postmortem analysisComplete autopsies 10 patients deceased from COVID-19.Complete autopsy of 9 patients.Limited autopsy of 1 patient. SARS-CoV-2 RT-PCR: positive in extrarespiratory tissues of 4 of 5 patients.Histopathological examinations: diffuse alveolar damage, thrombosis, haemophagocytosis, immune cell depletion, pancreatitis, pericarditis, adrenal microinfarction, secondary disseminated mucormycosis, and brain microglial activation. Subgenomic viral RNA transcripts were detected on 4 of 5 patients in heart, kidney, liver, lungs, bone marrow, or trachea.
Schepis et al Pancreas In vitro analysis One patient with pancreatic pseudocyst and SARS-CoV-2 associated pneumonia. Collection of pancreatic pseudocyst fluid sample. SARS-CoV-2 RT-PCR: positive in pancreatic pseudocyst fluid sample for E, RdRP, and N genes (CT values = 21.19, 24.04, and 23.44 respectively).Confirmed by qRT-PCR: 2.4 × 106 cps/mL within the pseudocyst fluid. ND
Skok et al Throat, lungs, intestine, gallbladder, and brain Postmortem analysis 28 COVID-19 positive patients.Swabs were taken postmortem during autopsy (N = 19) or without autopsy (N = 9). SARS-CoV-2 RT-PCR: positive in the lungs and throat. Less frequently positive in the intestine. Negative in blood, bile, and the brain.SARS-CoV-2 RT-PCR on throat swabs: positive up to 128 h after death without significant increase of CT values.Immunohistochemistry: nucleocapsid protein of SARS-CoV-2 detected in bronchial and intestinal epithelium, bronchial glands and pneumocytes.Histopathological examinations: lungs: diffuse alveolar damage.Intestine: focal ischemic changes on 30% of cases. ND
COVID-19, coronavirus disease 2019; CT value, cycle threshold value; H&E, hematoxylin and eosin; ND, not determined; PCR, polymerase chain reaction; qRT-PCR, reverse transcription-quantitative PCR; RT-PCR, reverse transcription-PCR; SARS-CoV, severe acute respiratory syndrome coronavirus; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; sgRNA, subgenomic messenger RNA.

Conjunctiva and Cornea

Ocular manifestations have been reported during the course of the outbreak in adult and pediatric patients,69,70 and it has been a matter of speculation whether SARS-CoV-2 can directly infect ocular tissue. Several authors have identified conjunctivitis as the first or sole manifestation of COVID-19,71-73 but conjunctivitis incidence following SARS-CoV-2 infection is highly variable. Guan et al report that among 1099 COVID-19 cases, only 0.8% showed conjunctival congestion, whereas Chen et al identified it in 5% of 535 COVID-19 patients.74 The proportion of ocular manifestations rose to 31.6% in a number of case series.73 These differences may be attributed to the diverse methodologies and protocols of clinical examination applied by the authors. SARS-CoV-2 RNA has been detected by RT-PCR in tears and conjunctival secretions in some samples from subjects with COVID-19 who have developed ocular manifestations, particularly conjunctivitis71,72,75,76 but the proportion of RT-PCR positive tests in such samples is also highly variable depending on the studies, ranging from 0% to 11%.70,73,77,78 A postmortem analysis on eye bulbi from patients deceased because of respiratory insufficiency consecutive to COVID-19 failed to detect SARS-CoV-2 RNA in corneal tissues or ocular fluids.79 Conversely, SARS-CoV-2 RNA from conjunctival swabs has been detected in living COVID-19 patients without ocular manifestations. Arora et al found that 24% of the 75 moderate and severe COVID-19 patients of their cohort tested positive by RT-PCR analysis of tear samples, and these patients did not manifest any ocular symptoms.80 Some have suggested that the window for detection of SARS-CoV-2 in conjunctival swabs is short and ocular samples would need to be collected at the early stages of ocular infections.81 A low viral load due to antiviral properties of tears and dilution factor could also explain the difficulty to detect RNA material in tear samples. Interestingly, in a patient with a severe case of conjunctivitis, Colavita et al identified SARS-CoV-2 RNA from ocular swabs from early days after hospital admission until day 21 postadmission. The authors claim that the first RNA-positive ocular sample induced cytopathic effects a few days following inoculation in Vero E6 cells, and RT-PCR analysis showed SARS-CoV-2 replication. Unfortunately, those data were not published; thus, these results need to be confirmed as no other attempt at isolation of the virus from the eye of COVID-19 patients has succeeded to our knowledge.71 Several other questions remain to be elucidated as conjunctiva and cornea have not yet been identified as an entry gate for infection compared with the upper respiratory airways. The results of the inoculation experiment of SARS-CoV-2 in the conjunctiva of Rhesus macaques have shown a possibility of infection of the nasolacrimal system and throat, as revealed by the detection of viral RNA.82 The development of IgG antibodies against SARS-CoV-2 antigens only after inoculation of the virus in conjunctiva, and immunohistochemistry analysis identifying SARS-CoV-2 in damaged lobes of the lungs, also support the hypothesis of the conjunctiva serving as a port of entry for SARS-CoV-2.

Kidneys

In 2003, Ksiazek et al reported the isolation of SARS-CoV from the postmortem kidney tissue of a patient infected in Hong Kong.83 SARS-CoV was also isolated from urine.84 SARS-CoV-2 infection of the kidney has also been a matter of debate, especially when relying on electron microscopy. Researchers have proposed conflicting interpretations of viral-like particles observed in kidney tissue to represent SARS-CoV-285–88 versus clathrin-coated vesicles and microvesicular bodies.89-92 SARS-CoV-2 RNA detection in kidney tissue, despite detection in lung tissue from the same patient has been inconsistent.89,93,94 Although hybridization in situ and indirect immunofluorescence suggest the presence of SARS-CoV-2 in the glomerular epithelium,94 in endothelial cell and in tubular cells,85,94 these immunohistochemistry experiments must be considered preliminary and interpreted with caution when not performed with antibodies validated for formalin-fixed paraffin-embedded tissue or targeting SARS-CoV proteins rather than specifically SARS-CoV-2 proteins.85,93,95 Despite the detection of SARS-CoV-2 RNA in tissue samples, Remmelink et al did not observe direct histopathologic changes due to SARS-CoV-2 infection in the kidney in autopsies.93 These observations were different from the one made by Braun et al who detected SARS-CoV-2 RNA in kidney tissue of 60% of the 63 COVID-19 patients they autopsied and in 72% of the 32 patients who demonstrated acute kidney injury.96 In their letter, they report to have detected viral replication following Vero cells inoculation and culture with kidney tissue homogenate from one of their patients. The experiments, however, did not demonstrate the isolation of viable virus from the autopsied tissue. Instead, they used proxy indicators such as fold changes in viral protein and mRNA. Although the authors report that a 1000-fold viral load increase was detected by RT-PCR from cell culture supernatants, it is unclear which controls or standardization approaches were used for estimating increased viral RNA. It is also unclear how close estimated values were to assay cutoffs. The number of experimental replications and the error estimates generated for the quantified RNA values are also unclear. Braun et al also report that immunostaining revealed the presence of SARS-CoV-2 nonstructural protein 3 in Vero cells. It is unclear if this is an indicator of infection and replication or represents an artifact. It should also be noted that the addition of tissue homogenate over a cell line cannot rule out transfection of the cell line with viral RNA.97 Furthermore, as SARS-CoV-2 is a positive-sense RNA virus, its genome can act as mRNA and lead to low levels of protein expression in cell lines. If viral mRNA are able to enter the cell culture system, it is possible that genomic RNA encoding for open reading frame 1a, is translated into the nonstructural protein 3.98 This work requires further confirmation.

SARS-CoV-2 has also been isolated from urine specimens, but it is unclear if this represents an infection of the kidney, the bladder, or the urinary tract,99 or even contamination of urine specimens. Detection of viable SARS-CoV-2 in urine specimens is not a routine phenomenon with some studies not identifying SARS-CoV-2 RNA in urine samples9,37 and others reporting its detection.100 Two groups reported the detection of infection in urine samples from severe COVID-19 patients.101,102 Whether kidney infection by SARS-CoV-2 results in a viable virus in urine requires confirmation.

Lungs, Liver, and Heart

Lungs and airway tissues are targets of SARS-CoV-2. Infectious virus has been isolated from upper and lower respiratory tract.9,103 SARS-CoV-2 RNA has been detected by RT-PCR in lung tissue from several deceased COVID-19 positive patients,89,93,94,104,105 often with a high viral load.93 These results have been supported by immunohistochemical verification of SARS-CoV-2 proteins.89,93,94,105,106 Although histopathologic analysis revealed lung injuries by diffuse alveolar damage due to COVID-19, neither heart nor liver demonstrated lesions as the specific consequence of viral infection.93,104,106-111 Nonetheless, autopsies revealed the heterogeneity of organ injury, including heart, liver, and the intestine. It is important to note that qualitative and quantitative detection of SARS-CoV-2 RNA in the tissue of several organs from the same deceased patients was observed in autopsies.93,94 These results could be a consequence of SARS-CoV-2 tropism for kidney, liver, heart, bowel, and the intestine or might be a result of viral RNA detection in residual blood. Viral load measurements identified the highest levels of RNA in the lungs. Remmelink et al noted RNA detection in tissue was not associated with specific viral injury of the organs.

SARS-CoV-2 infection was not associated with hepatitis, and rarely with myocarditis, in the postmortem studies reported here. Schaller et al suggest it was unclear whether systemic inflammation could have been responsible for the observed myoepicardial alterations. They hypothesize that changes observed in the heart and liver are related to underlying diseases and comorbidities rather than represent a direct consequence of SARS-CoV-2 infection. Electron microscopy observation on 1 sample of endomyocardial tissue from heart biopsy of SARS-CoV-2 patient with respiratory distress and cardiogenic shock, who died ultimately of septic shock of bacterial origin, showed dense round envelope viral-like particles with spike-like structure on the surface. Tavazzi et al attributed this to viral particles harboring the same morphology as coronavirus.112 These particles were observed in interstitial cytopathic cells of the myocardium but not in cardiomyocytes. No other tests were performed to confirm the detection of SARS-CoV-2 at the ultrastructural level and the associated viral load. Pathologic analysis showed myocardial inflammation but absence of myocytes necrosis. Lindner et al used in situ hybridization analysis to observe SARS-CoV-2 genetic material in interstitial cells or macrophages in the myocardial tissue of deceased COVID-19 patients (mostly from pneumonia).113 SARS-CoV-2 RNA was detected in the cardiac tissue of 24 of the 39 patients autopsied (61.5%), among whom 16 had >1000 copies/μg of RNA. The authors claim to have identified negative-sense RNA, suggestive of infection in the 5 patients having the highest viral load in myocardium. However, since paraffin-embedded specimens could not be cultured, it is unclear whether these results represent true productive viral replication, experimental artifacts, the initial stages of an early blunted infection, or the presence of early genomic replication that did not lead to infectious virions. Interestingly in this context when the patients autopsied were not suspected of myocarditis, a viral load in myocardium was not found to be associated with increased mononuclear cell infiltration compared with what was observed for patients without detectable SARS-CoV-2 RNA in heart tissue.

Pancreas

Other studies failed to demonstrate the presence of viral RNA in several organs of autopsy cases,95,106 meaning that a tropism of the virus for the organs is not systematic. Whether SARS-CoV-2 targets the pancreas during COVID-19 course is still unknown, as the virus has not been isolated from pancreatic tissue at the time of writing this review. Several studies mention pancreatic enzyme abnormalities in a proportion of COVID-19 patients,59,114 and a few cases have been diagnosed with acute pancreatitis. Some viral infections may result in pancreatitis-like syndromes, but the etiology of pancreatic inflammation observed in some COVID-19 patients remains unclear.115,116 Uncontrolled hyperglycemia has also been reported in COVID-19 patients,117 but the causal role for SARS-CoV-2 infection of islets cells has not been confirmed. Consequentially, it is uncertain if COVID-19 induces pancreatic injury because of direct SARS-CoV-2 infection. SARS-CoV-2 RNA was detected by RT-PCR from pancreatic pseudocyst fluid that developed in a symptomatic COVID-19 patient as a complication of a recent acute edematous pancreatitis.118 The amplification of the 3 SARS-CoV-2 genes targeted was as low as 21.9, 24.04, and 23.44 for genes coding for envelope, RNA-dependant, RNA polymerase, and nucleocapsid proteins. A high viral load of 2.4 × 106 copies/mL was quantified by qRT-PCR in the pancreatic pseudocyst fluid. More studies are necessary to decipher if this SARS-CoV-2 genome detection represents a direct infection of pancreatic cells, inflammatory cells, or is a result of viral clearance from other infected tissues. Sampling and analysis of stool or tissue biopsy specimens would have also been informative.

Intestinal Tract

COVID-19 can manifest in gastrointestinal symptoms as reported by as many as 12% of patients.119 This was also the case for SARS-CoV patients. SARS-CoV was isolated from stool and the small intestine in autopsies and biopsy analyses.120,121 Rectal swabs and stool samples collected from COVID-19 patients allowed the detection of RNA of SARS-CoV-2. Several groups detected RNA in stool specimens from symptomatic, previously symptomatic, and even asymptomatic COVID-19 patients.9,122,123 Several studies reported on SARS-CoV-2 RNA detectable in stool, with the infectious virus also isolated.37,56,102,124,125

Subgenomic RNA Detection

Although studies evaluating SARS-CoV-2 isolation from tissues are limited, in the majority of biopsy or autopsy analysis, subgenomic RNA has been used by other researchers as a marker of active viral replication,9 and, therefore, presence of viable virus,126 suggesting potential infectivity. Subgenomic RNAs are a set of transcription products of complementary negative-sense genomic length RNA. Their synthesis results in series of RNA sequences of different length. SARS-CoV-2 subgenomic mRNAs are thought to code for several structural and accessory proteins. Because replication and transcription are required for subgenomic RNA synthesis, their detection has been considered an indication of active virus infection. Hanley et al have recently claimed to have identified subgenomic RNA transcripts in cells from heart, kidney, liver, lungs, bone marrow, or trachea samples collected from 4 patients deceased from COVID-19.127 One series of experiments suggests that subgenomic RNA was present in some organs. However, subgenomic RNA was not uniformly detected in all organs analyzed from each patient. The authors do not provide normalizing controls for subgenomic RNA levels and the robustness of the assay cutoff is unclear. No information was provided on the dynamic range of the assay and whether these positive values could potentially represent false-positive values hovering near the cutoff. Along with estimated high titers of virus in these organs, via RT-PCR, the authors conclude that there are “indications of viral replication” within nonpulmonary organs. Others note that the gold-standard for active viral replication is still cell culture propagation of SARS-CoV-2128 and 1 publication has suggested that some subgenomic RNA data may be artifactual and not represent active viral replication.129

TRANSMISSION OF SARS-COV-2 THROUGH GRAFTS OR TRANSPLANTATION

Our literature search identified 4 case reports of cells and organs transplantation from COVID-19 infected donors, and 3 cases of organ donors with 1 positive SARS-CoV-2 RT-PCR test the day of or the day before transplantation (Table 2).

TABLE 2. - Transplantations case reports
Reference Organ/tissue/cell type Type of transplantation Donor-derived transmission to the recipient Donors Recipients Organ description
Hong et al Liver ABO incompatible living donor liver transplantation. No transmission of SARS-CoV-2 detected. Pretransplant: the donor was healthy and had a mild febrile illness for a d before admittance. No respiratory or gastrointestinal symptoms. Temperature was 37.5°C.Day of transplantation: live biopsy of the liver. SARS-CoV-2 RT-PCR result negative.Day 3 posttransplantation: COVID-19 positive via NP and oropharyngeal swab and sputum specimens using real-time reverse transcription polymerase chain reaction (rRT-PCR) assay. SARS-CoV-2 RT-PCR on blood specimen was negative. Day 7 posttransplantation: COVID-19 negative via NP and oropharyngeal swab. Pretransplant: no symptoms of COVID-19, no history of travels abroad, and no exposure to COVID-19 positive patients.COVID-19 rRT-PCR tests via both NP swab and serum were negative from d 3 until d 14 posttransplant. No evidence of viral infection on the donor liver biopsy.
Heinz et al Liver Living donor liver allograft. The recipient contracted the infection (either preliver transplant or through the donated tissue). Day 3 posttransplantation: transient sore throat and cough. Day 4 posttransplantation: tested positive for SARS-CoV-2 via NP RT-PCR. Day 4 posttransplantation: nasal congestion and diarrhea.Low-grade fever. Moderate respiratory distress. Patchy bilateral lung opacities.COVID-19 rRT-PCR tests via NP swab were positive.Day 4 posttransplantation: again, tested positive via NP SARS-CoV-2 RT-PCR. Moderate acute cellular rejection and moderate lobular hepatitis observed on liver biopsy.
Lázaro del Campo et al Bone marrow transplant Allogeneic hematopoietic cell transplant. No transmission of SARS-CoV-2 detected. Related matched donor was asymptomatic before mobilization and the apheresis. Posttransplantation: asymptomatic consecutive SARS-CoV-2 NP RT-PCR tests were negative. ND
Anurathapan et al Bone marrow transplant HLA-matched sibling hematopoietic stem cells transplant. No transmission of SARS-CoV-2 detected. One d pretransplantation: SARS-CoV-2 RT-PCR on NP swab was positive. Asymptomatic. Retrieved marrow was tested negative for SARS-CoV-2 by RT-PCR. Asymptomatic. RT-PCR SARS-CoV-2 in NP swab and blood. ND
Neidlinger et al Liver, heart, and kidneys Deceased donor organs transplantation. No transmission of SARS-CoV-2 detected. Liver donor: 1 d pretransplantation: 1 NP RT-PCR positive and 2 others RT-PCR tests negatives (BAL, stool); IgG positive; IgM negative.Heart and kidneys donor: 1 NP SARS-CoV-2 RT-PCR negative at hospital admission; 1 BAL SARS-CoV-2 RT-PCR negative (d 2 postadmission); 1 SARS-CoV-2 RT-PCR positive on stool sample; and 1 NP SARS-CoV-2 RT-PCR negative (d 3 postadmission). Liver recipient: d 1 to 23 posttransplantation: 3 SARS-CoV-2 RT-PCR negatives (biopsy; NP). The recipient died 1 mo later of multisystem organ failure.Heart recipient: NP SARS-CoV-2 RT-PCR negative.Left kidney recipient: NP SARS-CoV-2 RT-PCR negative.Right kidney recipient: NP SARS-CoV-2 RT-PCR negative. ND
Ceulemans et al Lungs; liver Double-lung transplantation;liver transplantation. No transmission of SARS-CoV-2 detected. COVID-19 confirmed 3 mo before transplantation.Day of transplantation: SARS-CoV-2 RT-PCR positive on lung parenchyma biopsy; SARS-CoV-2 viral culture negative; RT-PCR negative (NP, BAL); IgG positive. Lungs recipient: d 1 to 90 posttransplantation: SARS-CoV-2 RT-PCR negative (NP; BAL; bronchoscopic biopsy); viral culture on BAL negative; chest CT and X-ray: normal; IgG negative.Liver recipient: BAL SARS-CoV-2 RT-PCR negative posttransplantation. No pulmonary infiltrates; no signs of interstitial lung disease; mild subpleural emphysema; no signs of virus-induced injury.
BAL, bronchoalveolar lavage; COVID-19, coronavirus disease 2019; CT, cycle threshold; ND, not determined; NP, nasopharyngeal; PCR, polymerase chain reaction; rRT-PCR, real-time reverse transcription-PCR; RT-PCR, reverse transcription-PCR; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.

Hematopoietic Stem Cells

Two case reports of allogenic HSC transplantation from COVID-19 donors occurred in Spain and in Thailand in March and in April 2020, respectively.130,131 Ultimately, in both cases, HSC transplantation was successful and no transmission of SARS-CoV-2 was documented despite consecutive SARS-CoV-2 nasopharyngeal RT-PCR tests and close surveillance for COVID-19 symptoms in the recipients. In the first case, no preliminary tests were performed before transplantation as the donor did not manifest with symptoms before donation.130 The medical team was informed of the donor’s COVID-19 positive status 3 d after the transplantation. In the second case, the donor and his family (mother and aunt) were identified and confirmed to be positive for COVID-19 by RT-PCR, but because the patient was unlikely to survive without transplantation, and neither the donor nor the recipient’s family members manifested any symptoms, a decision was taken to proceed.131 A sample of bone marrow was tested, and the RT-PCR result was negative.

Lungs

Ceulemans et al report on double-lung transplantation from a donor who had COVID-19 symptoms 3 months pretransplant.132 Upon admission with intracranial bleeding, the patient had a first negative SARS-CoV-2 RT-PCR result on nasopharyngeal swab. Detection of SARS-CoV-2-IgG confirmed a previous infection. Eight days after admission, the patient was evaluated for donation. SARS-CoV-2 RT-PCR on nasopharyngeal swab and lower lobe BAL were negative. Right upper and left lower lobe biopsies were submitted for SARS-CoV-2 RT-PCR analysis. The right upper biopsy sample demonstrated SARS-CoV-2 RNA amplification (CT value of 35). The team proceeded with transplantation. BAL samples collected from the recipient for SARS-CoV-2 PCR analysis and viral culture on days 15, 34, and 90 posttransplant (PT) were negative. A viral culture of a lung biopsy was also negative. Chest imaging revealed no lung injury, and SARS-CoV-2 serology was also negative. Thus, there was no evidence for SARS-CoV-2 transmission.

Liver

We have identified 2 case reports of liver transplantation from COVID-19 positive donors. The first case, from Korea, described an ABO incompatible living donor liver transplantation between a 28-y-old donor and her mother of 57 y that took place in February 2020, before community spread of COVID-19.133 Donor and recipient had not met during the 14 d preceding the intervention. The recipient reported no travel history or exposure to COVID-19 patients. The donor was admitted to the hospital 1 day before the intervention and reported a mild febrile illness since the day prior, without any other symptoms. The donor was informed 2 d after transplantation that he had been in close contact with a COVID-19 case and subsequent SARS-CoV-2 RT-PCR test was positive. From day 4 to 18 PT, all RT-PCR tests on nasopharyngeal or blood samples of the recipient were negative. Her chest x-rays were normal, and she did not show any COVID-19 symptoms. The results of SARS-CoV-2 RT-PCR on liver biopsy were also negative and histopathologic analysis revealed no architecture disorder or evidence of inflammation. The recipient was maintained at the hospital until day 69 because of intra-abdominal infection and hepatic artery occlusion but was considered to not have developed any postoperative COVID-19 symptoms or infection.

The second case involved a living related liver transplant performed in March 2020 in the United States between a mother and her 6-mo-old infant with end-stage liver disease.134,135 No signs or symptoms were observed in either donor or recipient before the intervention. An RT-PCR test was not done to verify viral presence at that time. The mother developed a cough and sore throat 3 d PT. She tested positive for SARS-CoV-2 by RT-PCR analysis on nasopharyngeal swab performed a day later. The recipient started to have diarrhea and nasal congestion on day 4 PT. The infant developed fever and patchy bilateral opacities on the lungs. No complications related to the transplantation were observed until these symptoms developed. SARS-CoV-2 infection was confirmed in the recipient by RT-PCR test on a nasopharyngeal sample and high viral load was still measured on day 12 PT, with CT count of 19.9. Liver biopsies taken between day 7 and 30 PT demonstrated moderate acute cellular rejection and moderate lobular hepatitis due to viral infection since large clusters of apoptotic hepatocytes were observed, similar to other acute viral liver infections. Hybridization in situ experiment was interpreted to detect SARS-CoV-2 in hepatocytes, but the test was not yet validated when performed. The patient was discharged on day 22 PT as symptoms improved. Unfortunately, no RT-PCR test was done on liver biopsy or on the recipient at the time of transplantation. The mother was in close contact with her child before the intervention, which makes it impossible to conclude if an infection of the recipient occurred via liver tissue or airways. A nosocomial infection of the recipient before the transplantation could not be excluded either. Postoperative infection by the mother seems improbable since postoperative care was provided by 2 independent teams and in the absence of physical contact. Although the first case of liver transplantation reported here showed no transmission of SARS-CoV-2, donor-derived transmission is possible in the second case.

Two additional liver transplants from donors with a SARS-CoV-2 RT-PCR positive result in proximity to transplantation have been reported.132,136 Neidlinger et al describe a patient who had a cardiac arrest and at first tested negative for SARS-CoV-2 RT-PCR on a nasopharyngeal swab.136 When being evaluated for organ donation 3 d later, he tested positive to SARS-CoV-2 RT-PCR on a nasopharyngeal swab. Two other negative RT-PCR results were obtained on the same day from stools and BAL. Serological analysis revealed that the donor was SARS-CoV-2-IgG positive but IgM negative. Transplantation was performed the following day. RT-PCR in the recipient on days 1, 3, and 23 PT was negative. The recipient died 1-month PT due to multisystem organ failure.

The donor reported by Ceulemans et al also donated a liver to a different recipient.132 A BAL sample analyzed by RT-PCR in the liver recipient confirmed no SARS-CoV-2 transmission.

Heart and Kidneys

Neidlinger et al also reported on a deceased donor, with no previous history of infection, whose kidneys, heart, and liver were allocated following 2 negative SARS-CoV-2 RT-PCR results.136 During organ recovery, a SARS-CoV-2 RT-PCR test result on a stool sample came back positive, but another RT-PCR test performed on a nasopharyngeal swab was negative. Only kidneys and heart transplantations were performed. A 30-d follow-up of the 3 recipients, including RT-PCR testing, has shown no evidence of SARS-CoV-2 transmission.

CONCLUSION

To our knowledge, this overview is the first to capture the various routes of SARS-CoV-2 transmission during living or deceased organ, tissue, or cellular transplantation. We conducted an extensive literature search to identify clinical cases of CTO transplantation from COVID-19 positive donors to recipients. We found laboratory evidence to support biologically plausible mechanisms of SARS-CoV-2 transmission in transplantation, though the likelihood of transmission varies by organ and tissue and type. Moreover, techniques for viral detection and tests of infectivity/virulence vary widely and suggest a lack of standardized laboratory protocols. Despite those findings, during the review period, there has been no documented case of transmission of SARS-CoV-2 by CTO transplantation.

Considering the currently available data, there remains a theoretical risk of transmission through transplantation. It is currently impossible, however, to convert this theoretical risk into a calculable risk because of the inconsistency across the techniques used and the variable expression of the virus in different tissues. The fact that no cases have been linked to transplantation is somewhat reassuring from a systems safety standpoint. Yet, it remains to be established whether this is related to effective clinical and laboratory screening of potential donors or to low likelihood of transmission.

The novelty of the virus and the inconsistent methods applied to detect its viability and transmissibility limit the conclusions that can be drawn from this effort. At this stage of the COVID-19 pandemic, this overview can help identify gaps in the current state of knowledge.

Future work defining unified standards for the verification of viral presence and infectivity in organs and tissues may benefit the scientific and clinical community by providing more robust tools of infection monitoring and control. There is a need for research outlining standards for the verification of transmissible infection via CTO transplants that is sufficiently rapid to deploy when decisions on organ allocation are taken and can also serve for posttransplant surveillance.

Since the beginning of the pandemic, a consensus has emerged not to consider COVID-19 positive patients as potential living or deceased donors.137 This decision, combined with multiple other factors, notably pressure on healthcare system resources and the fear of postoperative transmission of SARS-CoV-2 to recipients, has led to a global decrease in transplantation procedures.138-140 However, some patients with life-threatening organ failure require timely access to transplantable organs. Since SARS-CoV-2 isolation from the respiratory tract of patients with mild COVID-19 disease does not exceed beyond the second week SSO,8,9,11 and repeat negative results following nucleic acid testing are highly recommended by some transplant societies for potential organ donors,141 a minimum delay of 21 d SSO could be considered when evaluating mild COVID-19 recovered patients as potential donors. A 2-wk delay from symptom resolution may also be considered.142 With the virus continuing to circulate worldwide, and the timeline for an effective, widely distributed vaccine still uncertain, clinicians will be forced to evaluate an increasing number of previously or actively COVID-19 infected patients as potential donors. It is thus imperative for the virology and infection control experts in the donation and transplantation communities to ensure that every potential donor who can safely donate their organs is considered and no recipient is put at risk for COVID-19 from a received graft.

REFERENCES

1. White SL, Rawlinson W, Boan P, et al. Infectious disease transmission in solid organ transplantation: donor evaluation, recipient risk, and outcomes of transmission. Transplant Direct. 2019; 5:e416
2. Len O, Garzoni C, Lumbreras C, et al. Recommendations for screening of donor and recipient prior to solid organ transplantation and to minimize transmission of donor-derived infections. Clin Microbiol Infect Off Publ Eur Soc Clin Microbiol Infect Dis. 2014; 20Suppl 710–18
3. Fung M, Babik JM. COVID-19 in immunocompromised hosts: what we know so far. Clin Infect Dis. 2020; 27:27
4. Azzi Y, Bartash R, Scalea J, et al. COVID-19 and solid organ transplantation: a review article. Transplantation. 2021; 105:37–55
5. Raja MA, Mendoza MA, Villavicencio A, et al. COVID-19 in solid organ transplant recipients: a systematic review and meta-analysis of current literature. Transplant Rev (Orlando). 2021; 35:100588
6. Craig-Schapiro R, Salinas T, Lubetzky M, et al. COVID-19 outcomes in patients waitlisted for kidney transplantation and kidney transplant recipients. Am J Transplant Off J Am Soc Transplant Am Soc Transpl Surg. 2020; 4:1576–1585
7. Loupy A, Aubert O, Reese PP, et al. Organ procurement and transplantation during the COVID-19 pandemic. Lancet. 2020; 395:e95–e96
8. Cevik M, Tate M, Lloyd O, et al. SARS-CoV-2, SARS-CoV, and MERS-CoV viral load dynamics, duration of viral shedding, and infectiousness: a systematic review and meta-analysis. Lancet Microbe. 2021; 2:e13–e22
9. Wölfel R, Corman VM, Guggemos W, et al. Virological assessment of hospitalized patients with COVID-2019. Nature. 2020; 581:465–469
10. La Scola B, Le Bideau M, Andreani J, et al. Viral RNA load as determined by cell culture as a management tool for discharge of SARS-CoV-2 patients from infectious disease wards. Eur J Clin Microbiol Infect Dis. 2020; 39:1059–1061
11. Bullard J, Dust K, Funk D, et al. Predicting infectious severe acute respiratory syndrome coronavirus 2 from diagnostic samples. Clin Infect Dis. 2020; 71:2663–2666
12. van Kampen JJA, van de Vijver DAMC, Fraaij PLA, et al. Duration and key determinants of infectious virus shedding in hospitalized patients with coronavirus disease-2019 (COVID-19). Nat Commun. 2021; 12:267
13. Liu WD, Chang SY, Wang JT, et al. Prolonged virus shedding even after seroconversion in a patient with COVID-19. J Infect. 2020; 81:318–356
14. Falsey AR, Formica MA, Treanor JJ, et al. Comparison of quantitative reverse transcription-PCR to viral culture for assessment of respiratory syncytial virus shedding. J Clin Microbiol. 2003; 41:4160–4165
15. Ip DKM, Lau LLH, Chan KH, et al. The dynamic relationship between clinical symptomatology and viral shedding in naturally acquired seasonal and pandemic influenza virus infections. Clin Infect Dis. 2016; 62:431–437
16. Hoehl S, Rabenau H, Berger A, et al. Evidence of SARS-CoV-2 infection in returning travelers from Wuhan, China. N Engl J Med. 2020; 382:1278–1280
17. Tong ZD, Tang A, Li KF, et al. Potential presymptomatic transmission of SARS-CoV-2, Zhejiang Province, China, 2020. Emerg Infect Dis. 2020; 26:1052–1054
18. Zou L, Ruan F, Huang M, et al. SARS-CoV-2 viral load in upper respiratory specimens of infected patients. N Engl J Med. 2020; 382:1177–1179
19. Bai Y, Yao L, Wei T, et al. Presumed asymptomatic carrier transmission of COVID-19. JAMA. 2020; 323:1406–1407
20. Hu Z, Song C, Xu C, et al. Clinical characteristics of 24 asymptomatic infections with COVID-19 screened among close contacts in Nanjing, China. Sci China Life Sci. 2020; 63:706–711
21. Pan X, Chen D, Xia Y, et al. Asymptomatic cases in a family cluster with SARS-CoV-2 infection. Lancet Infect Dis. 2020; 20:410–411
22. Chan JF-W, Yuan S, Kok K-H, et al. A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster. Lancet Lond Engl. 2020; 395:514–523
23. Wei M, Yuan J, Liu Y, et al. Novel coronavirus infection in hospitalized infants under 1 year of age in China. JAMA. 2020; 323:1313–1314
24. Kam K, Yung CF, Cui L, et al. A well infant with Coronavirus Disease 2019 with high viral load. Clin Infect Dis. 2020; 71:847–849
25. Woloshin S, Patel N, Kesselheim AS. False negative tests for SARS-CoV-2 infection - challenges and implications. N Engl J Med. 2020; 383:e38
26. Mohammadi A, Esmaeilzadeh E, Li Y, et al. SARS-CoV-2 detection in different respiratory sites: a systematic review and meta-analysis. Ebiomedicine. 2020; 59:102903
27. Lother SA. Preoperative SARS-CoV-2 screening: can it really rule out COVID-19? Can J Anaesth. 2020; 67:1321–1326
28. Kucirka LM, Lauer SA, Laeyendecker O, et al. Variation in false-negative rate of reverse transcriptase polymerase chain reaction-based SARS-CoV-2 tests by time since exposure. Ann Intern Med. 2020; 173:262–267
29. Leblanc JF, Germain M, Delage G, et al. Risk of transmission of severe acute respiratory syndrome coronavirus 2 by transfusion: a literature review. Transfusion. 2020; 60:3046–3054
30. Stanworth SJ, New HV, Apelseth TO, et al. Effects of the COVID-19 pandemic on supply and use of blood for transfusion. Lancet Haematol. 2020; 7:e756–e764
31. Kwon S-Y, Kim E-J, Jung YS, et al. Post-donation COVID-19 identification in blood donors. Vox Sang. 2020; 115:601–602
32. Essa MF, Elbashir E, Batarfi K, et al. Lack of transmission of SARS-CoV-2 by platelet transfusion from a COVID-19-positive donor in a hematopoietic stem cell transplantation patient. Pediatr Blood Cancer. 2020; 68:e28658
33. Cappy P, Candotti D, Sauvage V, et al. No evidence of SARS-CoV-2 transfusion transmission despite RNA detection in blood donors showing symptoms after donation. Blood. 2020; 136:1888–1891
34. Cho HJ, Koo JW, Roh SK, et al. COVID-19 transmission and blood transfusion: a case report. J Infect Public Health. 2020. doi: 10.1016/j.jiph.2020.05.001
35. Corman VM, Albarrak AM, Omrani AS, et al. Viral shedding and antibody response in 37 patients with middle east respiratory syndrome coronavirus infection. Clin Infect Dis. 2016; 62:477–483
36. Chang L, Yan Y, Wang L. Coronavirus disease 2019: coronaviruses and blood safety. Transfus Med Rev. 2020; 34:75–80
37. Wang W, Xu Y, Gao R, et al. Detection of SARS-CoV-2 in different types of clinical specimens. JAMA. 2020; 323:1843–1844
38. Huang C, Wang Y, Li X, et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet Lond Engl. 2020; 395:497–506
39. Corman VM, Rabenau HF, Adams O, et al. SARS-CoV-2 asymptomatic and symptomatic patients and risk for transfusion transmission. Transfusion. 2020; 60:1119–1122
40. Li W, Moore MJ, Vasilieva N, et al. Angiotensin-converting enzyme 2 is a functional receptor for the SARS coronavirus. Nature. 2003; 426:450–454
41. Hoffmann M, Kleine-Weber H, Schroeder S, et al. SARS-CoV-2 cell entry depends on ACE2 and TMPRSS2 and is blocked by a clinically proven protease inhibitor. Cell. 2020; 181:271–280.e8
42. Zhou P, Yang X-L, Wang X-G, et al. A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature. 2020; 579:270–273
43. Shang J, Wan Y, Luo C, et al. Cell entry mechanisms of SARS-CoV-2. Proc Natl Acad Sci U S A. 2020; 117:11727–11734
44. Ding Y, He L, Zhang Q, et al. Organ distribution of severe acute respiratory syndrome (SARS) associated coronavirus (SARS-CoV) in SARS patients: implications for pathogenesis and virus transmission pathways. J Pathol. 2004; 203:622–630
45. Hamming I, Timens W, Bulthuis ML, et al. Tissue distribution of ACE2 protein, the functional receptor for SARS coronavirus. A first step in understanding SARS pathogenesis. J Pathol. 2004; 203:631–637
46. Gu J, Gong E, Zhang B, et al. Multiple organ infection and the pathogenesis of SARS. J Exp Med. 2005; 202:415–424
47. Wrapp D, Wang N, Corbett KS, et al. Cryo-EM structure of the 2019-nCoV spike in the prefusion conformation. Science. 2020; 367:1260–1263
48. Chan JF-W, Chan K-H, Choi GK-Y, et al. Differential cell line susceptibility to the emerging novel human betacoronavirus 2c EMC/2012: implications for disease pathogenesis and clinical manifestation. J Infect Dis. 2013; 207:1743–1752
49. Yang L, Han Y, Nilsson-Payant BE, et al. A human pluripotent stem cell-based platform to Study SARS-CoV-2 tropism and model virus infection in human cells and organoids. Cell Stem Cell. 2020; 27:125–136.e7
50. Zhao B, Ni C, Gao R, et al. Recapitulation of SARS-CoV-2 infection and cholangiocyte damage with human liver ductal organoids. Protein Cell. 2020; 11:771–775
51. Qi F, Qian S, Zhang S, et al. Single cell RNA sequencing of 13 human tissues identify cell types and receptors of human coronaviruses. Biochem Biophys Res Commun. 2020; 526:135–140
52. Hikmet F, Méar L, Edvinsson Å, et al. The protein expression profile of ACE2 in human tissues. Mol Syst Biol. 2020; 16:e9610
53. Wang Y, Wang Y, Luo W, et al. A comprehensive investigation of the mRNA and protein level of ACE2, the putative receptor of SARS-CoV-2, in human tissues and blood cells. Int J Med Sci. 2020; 17:1522–1531
54. Chu H, Chan JF, Yuen TT, et al. Comparative tropism, replication kinetics, and cell damage profiling of SARS-CoV-2 and SARS-CoV with implications for clinical manifestations, transmissibility, and laboratory studies of COVID-19: an observational study. Lancet Microbe. 2020; 1:e14–e23
55. Ziegler CGK, Allon SJ, Nyquist SK, et al. SARS-CoV-2 receptor ACE2 Is an interferon-stimulated gene in human airway epithelial cells and is detected in specific cell subsets across tissues. Cell. 2020; 181:1016–1035.e19
56. Zhou J, Li C, Liu X, et al. Infection of bat and human intestinal organoids by SARS-CoV-2. Nat Med. 2020; 26:1077–1083
57. Lamers MM, Beumer J, van der Vaart J, et al. SARS-CoV-2 productively infects human gut enterocytes. Science. 2020; 369:50–54
58. Taneera J, El-Huneidi W, Hamad M, et al. Expression profile of SARS-CoV-2 host receptors in human pancreatic islets revealed upregulation of ACE2 in diabetic donors. Biology. 2020; 9:215
59. Liu F, Long X, Zhang B, et al. ACE2 expression in pancreas may cause pancreatic damage after SARS-CoV-2 infection. Clin Gastroenterol Hepatol. 2020; 18:2128–2130.e2
60. Monteil V, Kwon H, Prado P, et al. Inhibition of SARS-CoV-2 infections in engineered human tissues using clinical-grade soluble human ACE2. Cell. 2020; 181:905–913.e7
61. Nicin L, Abplanalp WT, Mellentin H, et al. Cell type-specific expression of the putative SARS-CoV-2 receptor ACE2 in human hearts. Eur Heart J. 2020; 41:1804–1806
62. Chen L, Li X, Chen M, et al. The ACE2 expression in human heart indicates new potential mechanism of heart injury among patients infected with SARS-CoV-2. Cardiovasc Res. 2020; 116:1097–1100
63. Leonardi A, Rosani U, Brun P. Ocular surface expression of SARS-CoV-2 receptors. Ocul Immunol Inflamm. 2020; 28:735–738
64. Sungnak W, Huang N, Bécavin C, et al.; HCA Lung Biological Network. SARS-CoV-2 entry factors are highly expressed in nasal epithelial cells together with innate immune genes. Nat Med. 2020; 26:681–687
65. Ma D, Chen CB, Jhanji V, et al. Expression of SARS-CoV-2 receptor ACE2 and TMPRSS2 in human primary conjunctival and pterygium cell lines and in mouse cornea. Eye (Lond). 2020; 34:1212–1219
66. Grajewski RS, Rokohl AC, Becker M, et al. A missing link between SARS-CoV-2 and the eye? ACE2 expression on the ocular surface. J Med Virol. 2021; 93:78–79
67. Zhou L, Xu Z, Castiglione GM, et al. ACE2 and TMPRSS2 are expressed on the human ocular surface, suggesting susceptibility to SARS-CoV-2 infection. Ocul Surf. 2020; 18:537–544
68. Hui KPY, Cheung MC, Perera RAPM, et al. Tropism, replication competence, and innate immune responses of the coronavirus SARS-CoV-2 in human respiratory tract and conjunctiva: an analysis in ex-vivo and in-vitro cultures. Lancet Respir Med. 2020; 8:687–695
69. Ma N, Li P, Wang X, et al. Ocular manifestations and clinical characteristics of children with laboratory-confirmed COVID-19 in Wuhan, China. JAMA Ophthalmol. 2020; 138:1079–1086
70. Valente P, Iarossi G, Federici M, et al. Ocular manifestations and viral shedding in tears of pediatric patients with coronavirus disease 2019: a preliminary report. J Am Assoc Pediatr Ophthalmol Strabismus JAAPOS. 2020; 24:212–215
71. Xia J, Tong J, Liu M, et al. Evaluation of coronavirus in tears and conjunctival secretions of patients with SARS-CoV-2 infection. J Med Virol. 2020; 92:589–594
72. Chen L, Deng C, Chen X, et al. Ocular manifestations and clinical characteristics of 535 cases of COVID-19 in Wuhan, China: a cross-sectional study. Acta Ophthalmol. 2020; 98:e951–e959
73. Wu P, Duan F, Luo C, et al. Characteristics of ocular findings of patients with coronavirus disease 2019 (COVID-19) in Hubei Province, China. JAMA Ophthalmol. 2020; 138:575–578
74. Guan W-J, Ni Z-Y, Hu Y, et al. Clinical characteristics of coronavirus disease 2019 in China. N Engl J Med. 2020; 382:1708–1720.
75. Atum M, Boz AAE, Çakir B, et al. Evaluation of conjunctival swab PCR results in patients with SARS-CoV-2 infection. Ocul Immunol Inflamm. 2020; 28:745–748
76. Colavita F, Lapa D, Carletti F, et al. SARS-CoV-2 isolation from ocular secretions of a patient with COVID-19 in Italy with prolonged viral RNA detection. Ann Intern Med. 2020; 173:242–243
77. Seah IYJ, Anderson DE, et al. Assessing viral shedding and infectivity of tears in coronavirus disease 2019 (COVID-19) patients. Ophthalmology. 2020; 127:977–979
78. Liu YC, Ang M, Ong HS, et al. SARS-CoV-2 infection in conjunctival tissue. Lancet Respir Med. 2020; 8:e57
79. Bayyoud T, Iftner A, Iftner T, et al. Absence of severe acute respiratory syndrome-coronavirus-2 RNA in human corneal tissues. Cornea. 2021; 40:342–347
80. Arora R, Goel R, Kumar S, et al. Evaluation of SARS-CoV-2 in tears of moderate to severe COVID-19 patients. Ophthalmology. 2020; 128:194–503
81. Guo D, Xia J, Shen Y, et al. SARS-CoV-2 may be related to conjunctivitis but not necessarily spread through the conjunctiva SARS-CoV-2 and conjunctiva. J Med Virol. 2020; 92:1757–1758
82. Deng W, Bao L, Gao H, et al. Ocular conjunctival inoculation of SARS-CoV-2 can cause mild COVID-19 in rhesus macaques. Nat Commun. 2020; 11:4400
83. Ksiazek TG, Erdman D, Goldsmith CS, et al.; SARS Working Group. A novel coronavirus associated with severe acute respiratory syndrome. N Engl J Med. 2003; 348:1953–1966
84. Xu D, Zhang Z, Jin L, et al. Persistent shedding of viable SARS-CoV in urine and stool of SARS patients during the convalescent phase. Eur J Clin Microbiol Infect Dis. 2005; 24:165–171
85. Diao B, Wang C, Wang R, et al. Human Kidney is a target for novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. medRxiv. 2020. doi: 10.1101/2020.03.04.20031120
86. Su H, Yang M, Wan C, et al. Renal histopathological analysis of 26 postmortem findings of patients with COVID-19 in China. Kidney Int. 2020; 98:219–227
87. Varga Z, Flammer AJ, Steiger P, et al. Electron microscopy of SARS-CoV-2: a challenging task - Authors’ reply. Lancet. 2020; 395:e100
88. Kissling S, Rotman S, Gerber C, et al. Collapsing glomerulopathy in a COVID-19 patient. Kidney Int. 2020; 98:228–231
89. Frelih M, Erman A, Wechtersbach K, et al. SARS-CoV-2 virions or ubiquitous cell structures? Actual dilemma in COVID-19 Era. Kidney Int Rep. 2020; 5:1608–1610
90. Roufosse C, Curtis E, Moran L, et al. Electron microscopic investigations in COVID-19: not all crowns are coronas. Kidney Int. 2020; 98:505–506
91. Smith KD, Akilesh S, Alpers CE, et al. Am I a coronavirus? Kidney Int. 2020; 98:506–507
92. Miller SE, Brealey JK. Visualization of putative coronavirus in kidney. Kidney Int. 2020; 98:231–232
93. Remmelink M, De Mendonça R, D’Haene N, et al. Unspecific post-mortem findings despite multiorgan viral spread in COVID-19 patients. Crit Care. 2020; 24:495
94. Puelles VG, Lütgehetmann M, Lindenmeyer MT, et al. Multiorgan and renal tropism of SARS-CoV-2. N Engl J Med. 2020; 383:590–592
95. Martines RB, Ritter JM, Matkovic E, et al.; COVID-19 Pathology Working Group. Pathology and pathogenesis of SARS-CoV-2 associated with fatal Coronavirus Disease, United States. Emerg Infect Dis. 2020; 26:2005–2015
96. Braun F, Lütgehetmann M, Pfefferle S, et al. SARS-CoV-2 renal tropism associates with acute kidney injury. The Lancet. 2020; 396:597–598
97. Hashemi A, Roohvand F, Ghahremani MH, et al. Optimization of transfection methods for Huh-7 and Vero cells: a comparative study. Cytol Genet. 2012; 46:347–353
98. ViralZone. Betacoronavirus. Available at https://viralzone.expasy.org/764?outline=all_by_species. Accessed October 19, 2020
99. Jefferson T, Spencer EA, Brassey J, et al. Viral cultures for COVID-19 infectious potential assessment – a systematic review. Clin Infect Dis. 2020ciaa1764. doi:10.1093/cid/ciaa1764
100. Kim JM, Kim HM, Lee EJ, et al. Detection and isolation of SARS-CoV-2 in serum, urine, and stool specimens of COVID-19 patients from the Republic of Korea. Osong Public Health Res Perspect. 2020; 11:112–117
101. Sun J, Zhu A, Li H, et al. Isolation of infectious SARS-CoV-2 from Urine of a COVID-19 patient. Emerg Microbes Infect. 2020; 9:991–993
102. Jeong HW, Kim S-M, Kim H-S, et al. Viable SARS-CoV-2 in various specimens from COVID-19 patients. Clin Microbiol Infect. 2020; 26:1520–1524
103. Zhu N, Zhang D, Wang W, et al. A novel Coronavirus from patients with pneumonia in China, 2019. N Engl J Med. 2020; 382:727–733
104. Barton LM, Duval EJ, Stroberg E, et al. COVID-19 Autopsies, Oklahoma, USA. Am J Clin Pathol. 2020; 153:725–733
105. Skok K, Stelzl E, Trauner M, et al. Post-mortem viral dynamics and tropism in COVID-19 patients in correlation with organ damage. Virchows Arch. 2021; 478:343–353
106. Yao XH, He ZC, Li TY, et al. Pathological evidence for residual SARS-CoV-2 in pulmonary tissues of a ready-for-discharge patient. Cell Res. 2020; 30:541–543
107. Menter T, Haslbauer JD, Nienhold R, et al. Postmortem examination of COVID-19 patients reveals diffuse alveolar damage with severe capillary congestion and variegated findings in lungs and other organs suggesting vascular dysfunction. Histopathology. 2020; 77:198–209
108. Xu Z, Shi L, Wang Y, et al. Pathological findings of COVID-19 associated with acute respiratory distress syndrome. Lancet Respir Med. 2020; 8:420–422
109. Tian S, Xiong Y, Liu H, et al. Pathological study of the 2019 novel coronavirus disease (COVID-19) through postmortem core biopsies. Mod Pathol. 2020; 33:1007–1014
110. Schaller T, Hirschbühl K, Burkhardt K, et al. Postmortem examination of patients with COVID-19. JAMA. 2020; 323:2518–2520
111. Beigmohammadi MT, Jahanbin B, Safaei M, et al. Pathological findings of postmortem biopsies from lung, heart, and liver of 7 deceased COVID-19 patients. Int J Surg Pathol. 2020; 29:135–145.
112. Tavazzi G, Pellegrini C, Maurelli M, et al. Myocardial localization of coronavirus in COVID-19 cardiogenic shock. Eur J Heart Fail. 2020; 22:911–915
113. Lindner D, Fitzek A, Bräuninger H, et al. Association of cardiac infection with SARS-CoV-2 in confirmed COVID-19 autopsy Cases. JAMA Cardiol. 2020; 5:1281–1285
114. Wang F, Wang H, Fan J, et al. Pancreatic injury patterns in patients with coronavirus disease 19 pneumonia. Gastroenterology. 2020; 159:367–370
115. Thaweerat W. Current evidence on pancreatic involvement in SARS-CoV-2 infection. Pancreatology. 2020; 20:1013–1014
116. Rawla P, Bandaru SS, Vellipuram AR. Review of infectious etiology of acute pancreatitis. Gastroenterology Res. 2017; 10:153–158
117. Bode B, Garrett V, Messler J, et al. Glycemic characteristics and clinical outcomes of COVID-19 patients hospitalized in the United States. J Diabetes Sci Technol. 2020; 14:813–821
118. Schepis T, Larghi A, Papa A, et al. SARS-CoV2 RNA detection in a pancreatic pseudocyst sample. Pancreatology. 2020; 20:1011–1012
119. Heneghan C, Spencer E, Brassey J, et al. SARS-CoV-2 and the role of orofecal transmission: systematic review. medRxiv. 2020; 10:231.
120. Chan KH, Poon LL, Cheng VC, et al. Detection of SARS coronavirus in patients with suspected SARS. Emerg Infect Dis. 2004; 10:294–299
121. Leung WK, To KF, Chan PK, et al. Enteric involvement of severe acute respiratory syndrome-associated coronavirus infection. Gastroenterology. 2003; 125:1011–1017
122. Park S, Lee C-W, Park D-I, et al. Detection of SARS-CoV-2 in fecal samples from patients with asymptomatic and mild COVID-19 in Korea. Clin Gastroenterol Hepatol. 2020. doi: 10.1016/j.cgh.2020.06.005
123. Tang A, Tong ZD, Wang HL, et al. Detection of Novel Coronavirus by RT-PCR in Stool Specimen from Asymptomatic Child, China. Emerg Infect Dis. 2020; 26:1337–1339
124. Xiao F, Sun J, Xu Y, et al. Infectious SARS-CoV-2 in Feces of Patient with Severe COVID-19. Emerg Infect Dis. 2020; 26:1920–1922
125. Zhang Y, Chen C, Zhu S, et al. Isolation of 2019-nCoV from a stool specimen of a laboratory-confirmed case of the coronavirus disease 2019 (COVID-19). China CDC Wkly. 2020; 2:123–124
126. Wu HY, Brian DA. Subgenomic messenger RNA amplification in coronaviruses. Proc Natl Acad Sci U S A. 2010; 107:12257–12262
127. Hanley B, Naresh KN, Roufosse C, et al. Histopathological findings and viral tropism in UK patients with severe fatal COVID-19: a post-mortem study. Lancet Microbe. 2020; 1:e245–e253
128. Vijayan A, Humphreys BD. SARS-CoV-2 in the kidney: bystander or culprit? Nat Rev Nephrol. 2020; 16:703–704.
129. Alexandersen S, Chamings A, Bhatta TR. SARS-CoV-2 genomic and subgenomic RNAs in diagnostic samples are not an indicator of active replication. Nat Commun. 2020; 11:6059
130. Campo PL del, López AR, Benito B de la C, et al. No transmission of SARS-CoV-2 in a patient undergoing allogeneic hematopoietic cell transplantation from a matched-related donor with unknown COVID-19. Transfus Apher Sci. 2020; 59:102921
131. Anurathapan U, Apiwattanakul N, Pakakasama S, et al. Hematopoietic stem cell transplantation from an infected SARS-CoV2 donor sibling. Bone Marrow Transplant. 2020; 55:1–2
132. Ceulemans LJ, Van Slambrouck J, De Leyn P, et al. Successful double-lung transplantation from a donor previously infected with SARS-CoV-2. Lancet Respir Med. 2020; 9:315–318
133. Hong HL, Kim SH, Choi DL, et al. A case of coronavirus disease 2019-infected liver transplant donor. Am J Transplant. 2020; 20:2938–2941
134. Heinz N, Griesemer A, Kinney J, et al. A case of an Infant with SARS-CoV-2 hepatitis early after liver transplantation. Pediatr Transplant. 2020; 24:e13778
135. Lagana SM, De Michele S, Lee MJ, et al. COVID-19–Associated hepatitis complicating recent living donor liver transplantation. Arch Pathol Lab Med. 2020; 144:929–932
136. Neidlinger NA, Smith JA, D’Alessandro AM, et al. Organ recovery from deceased donors with prior COVID-19: a case series. Transpl Infect Dis Off J Transplant Soc. 2020e13503. doi:10.1111/tid.13503
137. Ahn C, Amer H, Anglicheau D, et al. Global Transplantation COVID Report March 2020. Transplantation. 2020; 104:1974–1983
138. Manara AR, Mumford L, Callaghan CJ, et al. Donation and transplantation activity in the UK during the COVID-19 lockdown. Lancet. 2020; 396:465–466
139. Reddy MS, Hakeem AR, Klair T, et al. Trinational study exploring the early impact of the COVID-19 pandemic on organ donation and liver transplantation at national and unit levels. Transplantation. 2020; 13:13
140. Charnaya O, Chiang TP, Wang R, et al. Effects of COVID-19 pandemic on pediatric kidney transplant in the United States. Pediatr Nephrol. 2021; 36:143–151
141. Trubin PA, Azar MM, Malinis M. Diagnostic testing of COVID-19 in solid organ transplantation: current clinical application and future strategies. Curr Transplant Rep. 2020; 7:390–398
142. European Centre for Disease Prevention and Control. Coronavirus disease 2019 (COVID-19) and supply of substances of human origin in the EU/EEA—Second update. Published December 10, 2020. Available at https://www.ecdc.europa.eu/en/publications-data/coronavirus-disease-2019-covid-19-and-supply-substances-human-origin. Accessed January 8, 2021

Supplemental Digital Content

Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.