Pathologic manifestations of levamisole-adulterated cocaine exposure

Abstract

Rheumatic manifestations of cocaine have been well described, but more recently, a dramatic increase in the levamisole-adulterated cocaine supply in the United States has disclosed unique pathologic consequences that are distinct from pure cocaine use. Most notably, patients show skin lesions and renal dysfunction in the setting of extremely high perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA). Unexpectedly, antibodies to myeloperoxidase, the typical target of p-ANCA, are relatively low if at all present. This discrepancy is due to the fact that p-ANCA seen in association with levamisole-adulterated cocaine exposure is often directed against atypical p-ANCA-associated antigens within the neutrophil granules such as human neutrophil elastase, lactoferrin, and cathepsin G. Biopsies of the skin lesions reveal leukocytoclastic vasculitis often involving both superficial and deep dermal vessels. Renal injury most typically manifests as crescentic and necrotizing pauci-immune glomerulonephritis. In this review, the manifestations of levamisole-adulterated cocaine-induced vasculitis are discussed with an emphasis on the typical histomorphologic findings seen on biopsy.

Virtual slides: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1764738711370019 .

Figure 1

Skin biopsy from a patient with exposure to levamisole-adulterated cocaine. A) Leukocytoclastic vasculitis involves both superficial and deep dermal vessels (hematoxylin and eosin stain, 40X). B) Numerous neutrophils and eosinophils surround and involve the vascular walls associated with leukocytoclastic debris and fibrinoid necrosis (hematoxylin and eosin stain, 400X).

Figure 2

Kidney biopsy from a patient with exposure to levamisole-adulterated cocaine. A) Necrotizing lesion characterized by the presence of fibrin (arrow) within the Bowman space with associated nuclear debris and incipient cellular crescent (hematoxylin and eosin stain, 400X). B) Cellular crescent with fibrin (arrow) within the Bowman space (methenamine silver-Periodic acid-Schiff stain, 400X). Note that the glomerular tuft is otherwise relatively normal, as is often seen in pauci-immune glomerulonephritis.