title: Cocaine-related retiform purpura: evidence to incriminate the adulterant, levamisole.
abstract: The term 'cocaine-induced pseudovasculitis' was coined to encompass a constellation of clinical and laboratory findings which mimics a systemic vasculitis but lacks confirmatory evidence of vasculitis on biopsy. Antineutrophil cytoplasmic antibodies reacting with human neutrophil elastase (HNE) have been reported to distinguish the cocaine-related syndrome from a true autoimmune vasculitis. Published cases of retiform purpura related to cocaine use are rare and an etiologic role for levamisole, a common adulterant of cocaine, has been postulated. We describe two female patients aged 39 and 49 years with cocaine-related retiform purpura, mainly affecting the legs. The initial clinical and serological profile in case 1 led to a suspicion of anti-phospholipid syndrome and in case 2 to Wegener's granulomatosis with an unexplained associated neutropenia. Skin biopsies revealed a mixed pattern of leukocytoclastic vasculitis and microvascular thrombosis in case 1 and pure microvascular thrombosis in case 2. Identification of anti-HNE antibodies in both patients linked their disease to cocaine. The mixed vasculopathic pattern in case 1 and the associated neutropenia in case 2, both known adverse effects of levamisole, point to this as the true etiologic agent. Urine toxicology shortly after a binge of cocaine use in each case was positive for levamisole.
authors.affiliation: Department of Pathology, Capital District Health Authority and Dalhousie University, 5788 University Avenue, Halifax, Nova Scotia, Canada. noreen.walsh@cdha.nshealth.ca
authors.forename: Noreen M G
authors.initials: NM
authors.lastname: Walsh
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Green
authors.forename: Rufus W
authors.initials: RW
authors.lastname: Burlingame
authors.forename: Sylvia
authors.initials: S
authors.lastname: Pasternak
authors.forename: John G
authors.initials: JG
authors.lastname: Hanly
mesh_terms: D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood; D016736:Antiphospholipid Syndrome / Q000097:blood / Q000139:chemically induced / Q000473:pathology; D018501:Antirheumatic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001706:Biopsy; D003042:Cocaine / Q000008:administration & dosage / Q000009:adverse effects*; D019970:Cocaine-Related Disorders; D003937:Diagnosis, Differential; D004342:Drug Hypersensitivity / Q000097:blood / Q000473:pathology*; D005260:Female; D014890:Granulomatosis with Polyangiitis / Q000097:blood / Q000139:chemically induced / Q000473:pathology; D006801:Humans; D007978:Levamisole / Q000008:administration & dosage / Q000009:adverse effects*; D008875:Middle Aged; D011693:Purpura / Q000097:blood / Q000139:chemically induced / Q000473:pathology*; D014657:Vasculitis / Q000097:blood / Q000139:chemically induced / Q000473:pathology*
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D018501:Antirheumatic Agents; D007978:Levamisole; D003042:Cocaine