While the diagnosis is primarily clinical, serum IgA levels and ESR can be elevated, urinalysis may demonstrate hematuria or proteinuria, and a CBC may reveal a leukocytosis with normal platelets.6
Suspect levamisole toxicity in patients using cocaine
Patients with levamisole toxicity present with sudden-onset tender plaques or bullae with necrotic centers within days of cocaine use. Case reports cite lesions primarily on the ears and cheeks. However, they can appear almost anywhere on the body.2,7-9 Physicians should have a high index of suspicion for levamisole toxicity in patients using cocaine who present with unexplained neutropenia or vasculitis.
Laboratory tests. If needed, tissue biopsy and urine detection of levamisole can be used to confirm the diagnosis.1
Management is straight-forward, but not simple
Skin lesions have been reported to improve several weeks after discontinuing use of contaminated cocaine1 (strength of recommendation [SOR]: C). Known users should be referred to drug treatment centers and counseled on the risks of use.
Our patient required hospitalization
When our patient came into the ED, he also complained of left thigh pain and swelling. A computed tomography scan revealed a deep sartorius abscess. The patient was admitted for ultrasound-guided aspiration of the abscess and IV antibiotics. His bilateral painful ear nodules persisted throughout his hospitalization, although his neutropenia resolved after 3 days.
Correspondence: Katherine Winter, MD, 101 Manning Drive, Chapel Hill, NC 27514; kwinter@unch.unc.edu