Prednisone and vardenafil hydrochloride for refractory levamisole-induced vasculitis

Levamisole is an immunomodulatory drug that was previously used to treat various medical conditions, including parasitic infections, nephrotic syndrome, and colorectal cancer. Over the last few years, increasing amounts of levamisole have been used as an adulterant in cocaine. Levamisole-cut cocaine has become a concern because it is known to cause a necrotizing purpuric rash, autoantibody production, and life-threatening leukopenia. Mixed histologic findings of vasculitis and thrombosis are characteristic of levamisole-induced purpura. The recommended management of levamisole-induced vasculitis currently involves withdrawal of the culprit along with supportive treatment. We describe a patient with levamisole-induced vasculitis who continued to develop skin lesions despite self-reported cocaine cessation. Complete resolution of cutaneous disease occurred with the addition of oral prednisone and vardenafil hydrochloride, suggesting the possibility of a new treatment option in patients with refractory disease. In addition, we review the clinical presentation, disease course, diagnostic approach, laboratory findings, histology, and management of levamisole-induced vasculitis. The harmful effects of levamisole-cut cocaine are serious enough that public alerts have been issued to increase awareness. Clinicians should consider the possibility of levamisole exposure in cocaine users presenting with any combination of fever, neutropenia, and necrotic skin lesions, especially in acral areas including the ears.