A 6-week-old infant girl was admitted to the hospital with impaired movement of the right arm for 24 hours, reduced feeding and intermittent fever up to 38.8°C for 3 days.
She was born at term via scheduled uncomplicated cesarean section with a birth weight of 3135 g and was discharged at 1 day of age. Beside a minor problem with establishing the breastfeeding, the neonatal period was uneventful.
On admission, the infant had a temperature of 37.4°C (rectal), heart rate of 178 beats/min, respiratory rate of 50 breaths/min, oxygen saturation of 100% in ambient air and weighed 4015 g. The right arm was pseudoparalytic, with seemingly pain when examining the right shoulder. There was no pain with passive movement of the right arm, the skin was intact without wounds and there was no sign of trauma. Examination of the left arm, shoulder and neck was normal, including normal palmar grasp reflex in both arms. The rest of the physical and neurologic examinations were normal.
Proximal osteoarticular infection of the right arm was suspected.
Laboratory data included a complete blood count, with hemoglobin of 10.0 g/dL (reference range 9.2–16.4 g/dL), platelets 754 × 109/L (135–620 × 109/L) and white blood cell (WBC) count of 33,000/μL (6000–16,300/μL). Neutrophils were 14,400/μL (1100–6000/μL; 43.6% of total WBCs), lymphocytes 14,600/μL (800–9100/μL; 44.2% of total WBCs), monocytes 3500/μL (200–5000/μL; 10.6% of total WBCs), eosinophils 170/μL (0–900/μL; 0.5% of total WBCs), basophils 90 /μL (0–300/μL; 0.3% of total WBCs) and metamyelo-, myelo- and promyelocytes 210/μL (0.6%). C-reactive protein was 93 mg/L (<10 mg/L), and erythrocyte sedimentation rate was 97 mm/h (2–20 mm/h). Routine renal function tests and electrolytes were all normal.
Radiograph, ultrasound (US) and magnetic resonance imaging (MRI) of the right upper extremity were normal. An unexpected finding on the MRI revealed the diagnosis.
Because of the small size of the patient, the abdomen was included in the MRI which revealed a 33 × 30 × 25 mm subcapsular liver abscess (LA) in segment VII (The Couinaud classification is used to describe functional liver anatomy; Fig.).
Because of motion artifacts, MRI could not determine whether the abscess was located subdiaphragmatic or intrahepatic. However, the US confirmed the intrahepatic location of the abscess.
Liver function tests showed increased alanine aminotransferase at 76 U/L (5–51 U/L) with the rest of the markers normal.
US-guided aspiration of the abscess revealed 1 ml of thick purulent material. Gram stain of the aspirate showed numerous Gram-positive cocci in clusters, and the culture yielded Staphylococcus aureus. Blood culture was without growth. The patient was treated with antibiotics for a total of 42 days. Initially, with intravenous cefuroxime 150 mg/kg divided every 8 hours for 7 days, which was changed to intravenous ceftriaxone 100 mg/kg once daily for 16 days, followed by oral amoxicillin/clavulanic acid 50/12.5 mg/kg divided every 8 hours for 19 days.
Within 4 days from the drainage, movement of the right arm normalized, fever ceased, inflammatory markers decreased and her feeding improved. Response to treatment was monitored by US and inflammatory markers once a week. Twenty-seven days after drainage of the abscess, the US scan was normal.
The infant’s immune workup showed that the IgA 0.15 g/L (0.01–0.34 g/L), IgG 4.6 g/L (2.6–10.4 g/L), IgM 0.55 g/L (0.06–0.66 g/L) and IgE 2 × 103 IU/L (<30 × 103 IU/L) were all normal. The T-, B- and NK-cell counts were also normal, as well as dihydrorhodamine test for chronic granulomatous disease.
On subsequent questioning, the mother recalled minor intermittent umbilical bleeding on days 8 to 10 of life when the cord fell off. This may have been a port of entry of an ascending infection.
At the age of 28 months she is well and thriving.
In children, the most common presentation of LA includes fever, abdominal pain and tender hepatomegaly.1 When located in the subcapsular area, an LA may cause diaphragmatic irritation, leading to referred pain to the right shoulder and/or coughing. In adults with LA, referred pain of the right shoulder as the initial symptom is reported to be as high as 24%.2 In the present case, the pseudoparalysis of the right arm was likely because of the referred pain to the shoulder.
The overall incidence of pediatric LA is estimated to be 25–79 per 100,000 admissions, with the highest incidence occurring in developing countries.1 However, the incidence of neonatal LA is unclear. One study reported an incidence of 25 per 100,000 neonatal admissions,3 while Tan et al4 report less than 100 cases of neonatal LA, worldwide, from 1930 to 2005. A more recent article from 2013 reviewed the literature and found 27 newly published cases over a 6-year period. This increased number of cases was suggested to be because of improved diagnosis with the availability of US.5
Predisposing factors for neonatal LA are prematurity, necrotizing enterocolitis, ascending infection via the umbilical or portal vein, umbilical catheterization, bacteremia and previous abdominal surgery.5,6
In addition, pediatric LA has been associated with sickle cell disease, congenital or acquired immunosuppression and obstructive biliary tract disease. It is also seen in children with inherited immunodeficiency disorders such as chronic granulomatous disease. In developing countries, helminthic hepatic infections and immunosuppression induced by protein malnutrition are also considered as predisposing factors for the development of LA.1
Pediatric LA secondary to appendicitis has declined significantly as a consequence of routine administration of antibiotics and early surgical intervention.1,7
The most common causative bacteria reported in patients with LA include S. aureus, Streptococcus pyogenes and Escherichia coli, but also Klebsiella, Pseudomonas, anaerobic bacteria and Corynebacterium acnes. With early diagnosis and appropriate treatment, the outcome is usually favorable.
Mortality rate was reported as high as 50%3; however, the latest meta-analysis showed a decline in the mortality rate to about 27%. The development of less invasive methods of drainage and the availability of broad-spectrum antibiotics have led to this significant decrease in mortality, particularly after 1990.8
The recommended treatment for neonatal pyogenic LA is drainage (percutaneous drainage or open surgery) in combination with long-term targeted antibiotic therapy. This is effective and associated with few complications.4,5,8,9 However, studies have shown that in uncomplicated cases with rapid convincing clinical response, noninterventional conservative long-term treatment with antibiotics alone may be sufficient.6,10
Because of the small number of cases, more studies are required in neonatal cases to define optimal treatment.
In conclusion, we report for the first time a case of neonatal pyogenic LA, presenting with pseudoparalysis of the right arm as a consequence of referred pain caused by subdiaphragmatic irritation. LA should be considered as a differential diagnosis in neonates and infants with impaired movement of the upper extremity when imaging of the limb is normal, in combination with nonspecific signs of infection and/or unexplained elevation of inflammatory markers.
1. Mishra K, Basu S, Roychoudhury S, et al. Liver abscess in children: an overview. World J Pediatr. 2010;6:210–216.
3. Doerr CA, Demmler GJ, Garcia-Prats JA, et al. Solitary pyogenic liver abscess in neonates: report of three cases and review of the literature. Pediatr Infect Dis J. 1994;13:64–69.
4. Tan NW, Sriram B, Tan-Kendrick AP, et al. Neonatal hepatic abscess in preterm infants:a rare entity? Ann Acad Med Singapore. 2005;34:558–564.
5. Oktav B, Serdar M, Cerreah CA, et al. Liver abscess: increasing occurrence in premature newborns. J Neonatal Surg. 2013;2:23.
6. Simeunovic E, Arnold M, Sidler D, et al. Liver abscess in neonates. Pediatr Surg Int. 2009;25:153–156.
7. Piqueras AI, Macia M, Ibañez L, et al. Pyogenic liver abscess with delayed presentation after appendectomy. Pediatr Infect Dis J. 2016;35:817–819.
8. Shah SI, Hudak J, Meng HD. Meta-analysis of factors associated with survival of neonatal hepatic abscess. J Pediatr Infect Dis. 2010;5:215–220.
9. Lee SH, Tomlinson C, Temple M, et al. Imaging-guided percutaneous needle aspiration or catheter drainage of neonatal liver abscesses: 14-year experience. AJR Am J Roentgenol. 2008;190:616–622.
10. Semerci SY, Babayigit A, Cebeci B, et al. Hepatic abscesses in preterm infants: report of three cases and review of the literature. J Trop Pediatr. 2016;62:255–260.