Levamisole Exposure and Hematologic Indices in Cocaine Users
ACADEMIC EMERGENCY MEDICINE 2011; 18:1141–1147 © 2011 by the Society for Academic Emergency Medicine Abstract
is an antihelminthic agent found in nearly 70% of seized U.S. cocaine. Sporadic case literature describes a life‐threatening agranulocytosis associated with levamisole exposure secondary to cocaine use. The authors compared the distribution of hematologic indices in a population of
cocaine users with and without a confirmed exposure to levamisole.
Methods: The records of all patients in the Lifespan hospital system who underwent comprehensive toxicologic testing between September 2009 and December 2009 (n = 799) were reviewed. Of these,
95 patients were eligible for inclusion (cocaine‐positive with a simultaneous complete blood count). Patients were grouped into levamisole‐positive (n = 47) and ‐negative (n = 48) groups. The primary outcome measures were total white blood
cell count (WBC), absolute neutrophil count (ANC), and absolute lymphocyte count (ALC); secondary outcome measures included percent neutrophils, lymphocytes, eosinophils, monocytes, and basophils, as well as identified co‐ingestants.
Results: Both groups had a similar
makeup of age, sex, and race. The total WBC count, ANC, and ALC were not significantly different between the two groups. There was no significant difference in relative proportion of neutrophils, eosinophils, basophils, or monocytes between the groups. There was one neutropenic patient in
the levamisole‐positive group, while three patients were neutropenic in the negative group. Additionally, a literature review of case reports describing levamisole‐induced agranulocytosis (n = 33) was conducted. In 52% of these cases, patients presented with
an oropharyngeal chief complaint; in an additional 27%, patients presented with soft tissue infections or purpura.
Conclusions: The overall incidence of neutropenia was 4.2% in all cocaine users and 2.1% in the levamisole‐positive group. A striking number of the reported
patients with levamisole‐associated neutropenia have presented to care with oropharyngeal complaints, vasculitis, or fever. A clinical algorithm for identifying levamisole toxicity in the emergency department setting is provided. Further research is necessary to determine the circumstances
required for levamisole‐associated neutropenia.
Document Type: Research Article
From the Division of Medical Toxicology, Department of Emergency Medicine, Alpert Medical School/Brown University (PRC, JBH, KMB), Providence, RI; and the Department of Pathology (WB) and the Center for Vascular Disease Research (JM), Rhode
Island Hospital, Providence, RI.
From the Division of Medical Toxicology, Department of Emergency Medicine, Alpert Medical School/Brown University (PRC, JBH, KMB), Providence, RI; and the Department of Pathology (WB) and the Center for Vascular Disease Research (JM), Rhode Island
Hospital, Providence, RI.
Publication date: November 1, 2011