Secondary Logo

Journal Logo

Original article

Evaluation of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in critical care patients with synthetic cannabinoid (bonzai) intoxication

Kaplan, Mustafaa; Tanoglu, Alpaslanb; Duzenli, Tolgab; Yildirim, Muhammeta; Sakin, Yusuf Serdarc,*; Salmanoglu, Musaa; Önem, Yalçina

Author Information
The Egyptian Journal of Critical Care Medicine: April 2018 - Volume 6 - Issue 1 - p 17-20
doi: 10.1016/j.ejccm.2018.03.002
  • Open


1. Introduction

The use of synthetic cannabinoids has been dramatically increasing among young individuals in many countries. The reasons of the rise in synthetic cannabinoid (SC) abuse are its cannabis-like effects, easy supply, cheap price and detection difficulties with routine toxicological screening methods [1,2]. Substances containing synthetic cannabinoids are named such as spice, K2, Bonzai and Jamaica in different countries They are typically consisted of several different SCs that mixed with herbal ingredients and smoked alike cannabis [2–4] and SCs produce cannabis-like effects in humans [2]. Although SCs show their effects by activating cannabinoid receptors in the body, they do not include cannabis or herbal products and formed from chemicals mixed with plant parts.). The exact number of the SC addiction is not known according to difficulties in detecting synthetic cannabinoid. In a survey study which include 14,966 participants, 17% of participants was reported to take SCs, and 7.2% of patients reported preference for SC over cannabis for reasons such as accessibility, cost, non-detection and effects [5]).

There are two cannabinoid receptor subgroups currently which are Cannabinoid 1 (CB1) receptors (mostly in the brain) and cannabinoid 2 (CB2) receptors (mostly in the immune and enteric nervous system). SCs typically make full agonist effects on CB1 receptors, thereby they cause maximum effect even at very low doses [6–9]. Sympathomimetic effects such as sweating, agitation and restlessness can be seen in synthetic cannabinoid toxicity in addition to marijuana's psychoactive effects [10]. In recent years, there have been reports of serious side effects with SC abuse such as rhabdomyolysis, renal failure, acute myocardial infarction, respiratory depression [1]. For diagnosis of intoxication; there must be suspicion and a good knowledge of signs and symptoms of this intoxication [10,11]. The main therapy of synthetic cannabinoid intoxication is supportive treatment for symptoms and benzodiazepines for agitation and anxiety [8–10].

Recently, the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been evaluated as new prognostic indicators for various malignancies [12–15]. Additionally, previous researches have exhibited that NLR and PLR are associated with mortality and morbidity in many chronic diseases, such as diabetes, hypertension and many other cardiac problems [14,16,17]. Currently, NLR has been accepted as a sign of subclinical inflammation, and used in combination with other inflammatory markers to determine inflammation in many diseases [13–16].

Abuse of SC has become a serious problem for public health institutions due to growing prevalence, variety of dosage/content and the lack of regulations for these drugs [18]. The aim of this study was to evaluate NLR and PLR in critical care patients with SC (bonzai) intoxication.

2. Materıals and methods

2.1. Patients

This was a retrospective case-control study assessing patients with SC (bonzai) intoxication between November 2015 and January 2016. Permission for the study was obtained from the local ethics committee of GATA Haydarpasa Training Hospital.

The study included 107 male patients who were stayed critical care because of synthetic cannabinoid ‘Bonsai’ intoxication and age and sex matched 40 healthy controls in GATA Haydarpasa Training Hospital. Due to the difficulties in detecting synthetic cannabinoids in laboratory tests, we include the patients due to their anamnesis, or their relatives' declarations. Age, gender, duration and frequency of abuse, complete blood count and routine blood tests (alanine aminotransferases, urine tests, blood creatinine level, erythrocyte sedimentation rate, C-reactive protein etc.), electrocardiographies (ECGs), physical examination findings were analyzed.

Patients with diseases such as diabetes, cardiac diseases, renal disorders, acute or chronic infections, celiac disease, inflammatory bowel disease, atherosclerotic disease, history of hypertension, malignancy, autoimmune disorders, hematological disorders, rheumatic diseases, and chronic obstructive lung diseases, as well as patients taking drugs such as aspirin, steroids, warfarin, heparin, antidiabetics, hyperlipidemics and antihypertensives, and patients with other addictions such as alcohol abuse were excluded from the study.

2.2. Laboratory analysis

The complete blood count (CBC) parameters such as white blood cell (WBC), hemoglobin (Hb) level, platelet count, mean platelet volume, NLR and PLR were recorded. The blood samples were obtained by vacutainer through the brachial vein into tubes containing dipotassium ethylenediaminetetraacetic acid (EDTA) in the intensive care unit on admission. It should be noted that, the CBC studies were performed within 45 min of the blood samples being drawn as a routine procedure of our hospital.

Complete blood count analysis was performed by using a fully automated hematologic analyzer (Abott, Cell-dyn Sapphire, USA) in biochemistry clinic. Serum levels of AST, ALT, albumin, total bilirubin and other routine biochemical parameters were evaluated by standard automated techniques (Abbott Architect C16000, USA). Although difficulty of detecting of SCs are well known, all the patients' blood and urine analysis for toxicology screen were performed for exact diagnosis.

2.3. Statistical analysis

Statistical analyses in this study were performed using SPSS ver. 15 software (SPSS Inc., Chicago, Illinois, USA). Demographic and clinical characteristics of patients, laboratory parameters, duration and frequency of abuse were determined with mean ± standard deviation, median, range and percentages (%). The variables were investigated using Kolmogorov-Smirnov/Shapiro Wilk's test to determine whether or not they are normally distributed. Independent samples t-tests were used to compare two groups. Receiver operating characteristic (ROC) curve analysis was used to identify optimal cut-off values of NLR and PLR.

3. Results

The mean age of the patients was 21.74 ± 1.57 and healthy controls was 22.62 ± 2.9 years (p > 0.05). All the patients and healthy controls were smokers (3 to 7 packages/week), and didn't have regular alcohol consumption. The patients in both group didn't have any comorbid disease. According to complaints; 10 patients (% 9.34) had sudden aggression, 36 patients (% 33.6) had dyspnea and chest pain and cardiac effects (mainly bradycardia), 24 patients had (% 22.4) confusion and fainting, 14 patients had (% 13) dizziness and drowsiness, 8 patients had (% 7.4) hallucinations (Table 1). Fortunately, none of the patients died as a result of drug abuse.

Table 1
Table 1:
Patient percentages according to complaints (n: number of patients, %: percentage value).

We couldn't detect the type of SCs in all patients, due to the abundant form of SCs and undetectable property of SCs in blood and urine tests. When comparing SCs intoxication with healthy control group, we found significant differences for platelet count, WBC count, NLR and PLR. The mean WBC value of the patients and healthy controls was 9.43 ± 3.27 × 103/mm3 and 7.05 ± 2.12 × 103/mm3 (p < 0.001), respectively. The mean platelet count (237.33 ± 60 × 103/mm3 vs 263.90 ± 65.98 × 103/mm3, p = 0.022), and PLR values of the patients were significantly lower (114.43 ± 36.39 vs 133.94 ± 45.27, p = 0.008) and NLR counts were significantly higher (3.17 ± 1.95 vs 2.32 ± 1.27, p = 0.003) than healthy controls (Table 2). Additionally, the results of the inflammatory tests of the patients, such as erythrocyte sedimentation rate and C-reactive protein were not different from the control group (p > 0.05).

Table 2
Table 2:
Comparison of demographic and laboratory parameters between two groups. Although the WBC and RBC count of the patients were in normal range, they were significantly different from control group (WBC: White blood cell; RBC: Red blood cell; MCV: Mean corpuscular volüme; RDW: Red cell distribution width; NLR: Neutrophil to lymphocyte ratio; PLR: Platelet to lymphocyte ratio).

When we performed ROC analysis, the MPV and NLR values were significantly different between groups (Fig. 1). Routine blood test results of patients were exhibited in Table 3.

Fig. 1.
Fig. 1.
Table 3
Table 3:
Laboratory values of patients.

4. Dıscussıon

This study was demonstrated the changes of NLR and PLR levels in critical care patients with SC intoxication. To the best of our knowledge, this is the first study in this topic.

NLR demonstrates the balance between neutrophils and lymphocytes and has been accepted as a putative marker for reflecting systemic inflammation [19]. Indeed, elevated NLR has been shown in relation with cardiovascular mortality [20]. The high NLR is a result of raised neutrophil count and diminished lymphocyte count. Increased serum cortisol levels, as a result of the exposure to stress of the body, may lead for such change. The conditions such as inflammation, many kinds of infections, drugs, intoxications and traumas could trigger the production of neutrophil and speed up the apoptosis of lymphocytes [19–21]. Additionally, increase of the neutrophil number is associated with the inflammatory process which may contribute to thrombotic state and bad cardiac outcomes. Previously, many researches have been demonstrated that NLR and PLR are significant risk predictors of bad cardiac outcomes and even short-term mortality for many diseases [21–24].

Currently, PLR has been considered as a new cheap and readily available marker of systemic inflammation and it consolidates the predictive risk of platelet and lymphocyte counts [25,26]. It has been suggested that PLR is a better prognostic marker than platelet or lymphocytes alone in predicting certain cardiovascular diseases [26]. Recently, it has been shown that the PLR is a new prognostic value of inflammation for many types of cardiovascular disease including coronary artery disease, atherosclerosis, hypertension, and peripheral arterial disease [27,28], Raised levels of thrombocytes reflect underlying inflammatory conditions, because thrombocytes are acute phase reactants that are produced in case of various stimuli including inflammatory conditions, systemic infections, bleeding, and tumors [26–28]. On the other side, decreased number of lymphocytes indicates an uncontrolled inflammatory pathway. Therefore, an elevated PLR is an useful inflammatory tool as it reflects the increase in platelet count, and decrease in lymphocyte count in an inflammatory state [14,25]. Although high levels of PLR have been indicated as a prediction of long term survival in different studies in chronic inflammatory processes [29,30], we found lower PLR in the patient differently from other inflammatory diseases in the current literature. We think that this inconsistency should be due to cannabinoid intoxication. It has been shown that higher doses of endocannabinoids reduced the response to TRAP activation associated with a decrease of platelet count [31]. In this study, it has been shown that anandamide causes concentration dependent platelet reduction of platelets. Consistently, we found lower platelet values in the patients when compared to healthy controls. Therefore, lower values of PLR are according to lower levels of platelets as a cause of high cannabinoid concentrations, and low PLR would be a predictor of cannabinoid intoxication. Additionally, our patients didn't have chronic inflammatory comorbidities before and didn't have mortality outcome at the end of the surveillance.

In this study, we also found significantly different platelet levels among SC intoxicated patients. As described before, we think that this result was due to consequence of cannabinoid intoxication. Moreover, in the present research, we selected PLR as a potential marker because it is readily calculated using the results of routine peripheral blood tests, and reflects systemic inflammation. Compatible with this whole data above, we observed mostly cardiac side effects among critical care patients with cannabinoid intoxication, and NLR and PLR were significantly changed. An exact explanation for this data remains unclear and is yet to be elucidated. Nonetheless, as a favorable outcome no patients of us were died. Young age and absence of co-morbidities may explain this benign outcome.

Our study had some limitations. First, our study was a retrospective study. Therefore, we couldn't reach the patients' all data. Secondly, only 107 male patients with SC intoxication were included in the current research. Because our hospital is a military hospital and generally cares for military personnel, we only performed the analysis for males. In contrary, young age and absence of co-morbidities and strict exclusion criteria are powerful sides of the current research. Finally study population was relatively small. Larger study population would provide higher statistical power.

In conclusion, our results have shown that PLR and NLR are significantly affected in critical care patients with synthetic cannabinoids toxicity. Although we can-not clearly conclude the underlying pathological process of these changes, we believe that these findings may open the way for further studies searching the role of PLR and NLR in SC toxicity.

Conflict of interest statement

The authors declare that they have no conflict of interest to the publication of this article.


This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.


[1] Sedefov R, Gallegos A, King L, Lopez D, Auwärter V, Hughes B, et al. Understanding the ‘spice’ phenomenon. Thematic papers, European Monitoring Centre for Drugs and Drug Addiction; 2009.
[2] Brents LK, Prather PL. The K2/Spice Phenomenon:emergence, identification, legislation and metabolic characterization of synthetic cannabinoids in herbal incense products. Drug Metab Rev 2014;4:72-85.
[3] Evren C, Bozkurt M. Sentetik Kannabinoidler: Son yılların Krizi. Düşünen Adam 2013;26:1-11.
[4] Vandrey R, Dunn KF, Fry JA, Garling ER. A survey study to characterize use of Spice products (synthetic cannabinoids). Drug Alcohol Depend 2012;120:238-241.
[5] Winstock AJ, Barratt MJ. Synthetic cannabis: a comparison of patterns of use and effect profile with natural cannabis in a large global sample. Drug Alcohol Depend 2013;131(1-2):106-111.
[6] Szily E, Bitter I. Designer drugs in psychiatric practice - a review of the literatüre and the recent situation in Hungary. Neuropsychopharmacol Hung 2013;15:223-231.
[7] Bretteville-Jensen AI, Tuv SS, Bilgrei OR, Fijeld B, Bachs L. Synthetic Cannabinoids and Cathinones: Prevalence and Markets. Forensic Sci Rev 2013;25:7-26.
[8] Aoun EG, Christopher PP, Ingraham JW. Emerging drugs of abuse:clinical and legal considerations. R I Med J 2014;97:41-45.
[9] Ibrahim S, Al-Saffar F, Wannenburg T. Unique Case of Cardiac Arrest following K2 Abuse. Case Rep Cardiol 2014;2014:120607.
[10] Hudson S, Ramsey J, King L, Timbers S, Maynard S, Dargan PI, et al. Use of high resolution accurate mass spectrometry to detect reported and previously unreported cannabinomimetics in ‘herbal high’ products. J Anal Toxicol 2010;34:252-260.
[11] Cohen J, Morrison S, Greenberg J, Saidinejad M. Clinical Presntation of Intoxication Due to Synthtetic Cannabinoids. Pediatrics 2012;129:1064-1067.
[12] Templeton AJ, Ace O, McNamara MG, Al-Mubarak M, Vera-Badillo FE, Hermanns T, et al. Prognostic role of platelet to lymphocyte ratio in solid tumors: a systematic review and meta-analysis. Cancer Epidemiol Biomark Prev 2014;23(7):1204-1212.
[13] Templeton A.J., McNamara M1, Šeruga B, Vera-Badillo FE, Aneja P, Ocaña A, et al. Prognostic role of neutrophil-to-lymphocyte ratio in solid tumors: a systematic review and meta-analysis. J Natl Cancer Inst 2014;106(6):dju124.
[14] Tanoglu A, Karagoz E, Yiyit N, Berber U. Is combination of neutrophil to lymphocyte ratio and platelet lymphocyte ratio a useful predictor of postoperative survival in patients with esophageal squamous cell carcinoma? Onco Targets Ther 2014;7:433-434.
[15] Tanoglu A, Karagoz E. Predictive Role of the Neutrophil-to-Lymphocyte Ratio in Patients with Advanced Hepatocellular Carcinoma Receiving Sorafenib. Asian Pac J Cancer Prev 2014;15(2):1063.
[16] Tamhane UU, Aneja S, Montgomery D, Rogers EK, Eagle KA, Gurm HS. Association between admission neutrophil to lymphocyte ratio and outcomes in patients with acute coronary syndrome. Am J Cardiol 2008;102(6):653-7.
[17] Guasti L, Dentali F, Castiglioni L, Maroni L, Marino F, Squizzato A, et al. Neutrophils and clinical outcomes in patients with acute coronary syndromes and/or cardiac revascularisation. A systematic review on more than 34,000 subjects. Thromb Haemost 2011;106(4):591-599.
[18] Merola G, Aturkib Z, D'Oraziob G, Gottardo R, Macchia T, Tagliaro F, et al. Analysis of synthetic cannabinoids in herbal blends by means of nano-liquid chromatography. J Pharm Biomed Anal 2012;71:45-53.
[19] Zahorec R. Ratio of neutrophil to lymphocyte counts-rapid and simple parameter of systemic inflammation and stress in critically ill. Bratisl Lek Listy 2001;102:5-14.
[20] Cho KH, Jeong MH, Ahmed K, Hachinohe D, Choi HS, Chang SY, et al. Value of early risk stratification using hemoglobin level and neutrophil-to-lymphocyte ratio in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention. Am J Cardiol 2011;107:849-856.
[21] Jo JY, Lee MY, Lee JW, Rho BH, Choi WI. Leukocytes and systemic inflammatory response syndrome as prognostic factors in pulmonary embolism patients. BMC Pulm Med 2013;13:74.
[22] Kundi H, Balun A, Cicekcioglu H, Cetin M, Kiziltunc E, Cetin ZG, et al. The relation between platelet-to-lymphocyte ratio and Pulmonary Embolism Severity Index in acute pulmonary embolism. Heart Lung 2015;44:340-343.
[23] Ma Y, Mao Y, He X, Sun Y, Huang S, Qiu J. The values of neutrophil to lymphocyte ratio and platelet to lymphocyte ratio in predicting 30 day mortality in patients with acute pulmonary embolism. BMC Cardiovasc Disord 2016;16:123.
[24] Kutlucan L, Kutlucan A, Basaran B, Dagli M, Basturk A, Kozanhan B, et al. The predictive effect of initial complete blood count of intensive care unit patients on mortality, length of hospitalization, and nosocomial infections. Eur Rev Med Pharmacol Sci 2016;20(8):1467-1473.
[25] Balta S, Demirkol S, Kucuk U. The platelet lymphocyte ratio may be useful inflammatory indicator in clinical practice. Hemodial Int 2013;17:668-9. [PubMed].
[26] Wang D, Yang JX, Cao DY, Wan XR, Feng FZ, Huang HF, et al. Preoperative neutrophil-lymphocyte and platelet-lymphocyte ratios as independent predictors of cervical stromal involvement in surgically treated endometrioid adenocarcinoma. Onco Targets Ther 2013;6:211-216.
[27] Sunbul M, Gerin F, Durmus E, Kivrak T, Sari I, Tigen K, et al. Neutrophil to lymphocyte and platelet to lymphocyte ratio in patients with dipper versus non-dipper hypertension. Clin Exp Hypertens 2014;36(4):217-221.
[28] Gary T, Pichler M, Belaj K, Hafner F, Gerger A, Froehlich H, et al. Platelet-to-lymphocyte ratio: a novel marker for critical limb ischemia in peripheral arterial occlusive disease patients. PLoS ONE 2013;8(7):e67688.
[29] Mao Y1, Fu Y2, Gao Y3, Yang A2, Zhang Q4. Platelet-to-lymphocyte ratio predicts long-term survival in laryngeal cancer. Eur Arch Otorhinolaryngol 2017 Dec 23. doi:10.1007/s00405-017-4849-4. [Epub ahead of print].
[30] Li H, Zhou Y, Ma Y, Han S, Zhou L. The prognostic value of the platelet-to-lymphocyte ratio in acute coronary syndrome: a systematic review and meta-analysis. Kardiol Pol 2017;75(7):666-673.
[31] Grambow E, Strüder D, Klar E, Hinz B, Vollmar B. Differential effects of endogenous, phyto and synthetic cannabinoids on thrombogenesis and platelet activity. BioFactors 2016 Nov 12;42(6):581-590. doi:

Synthetic cannabinoid; İntoxication; İntensive care unit; Neutrophil to lymphocyte ratio; Platelet to lymphocyte ratio

© 2018 by Lippincott Williams & Wilkins, Inc.