Vancomycin-Induced Leukocytoclastic Vasculitis: A Rare Complication From a Commonly Used Medication.

Leukocytoclastic vasculitis (LCV) is a cutaneous small vessel vasculitis that is characterized by the development of a non-blanching palpable purpura. Diagnosis is made by skin biopsy and histopathology which shows subepidermal acantholysis with dense neutrophilic infiltrate leading to fibrinoid necrosis of the dermal blood vessels. Etiology is generally idiopathic in most cases but secondary causes include chronic infections, malignancies, systemic autoimmune conditions, and medication use. Treatment involves supportive measures in the case of idiopathic LCV, and treatment of the offending condition or agent in LCV due to a secondary cause. A 59-year-old male presented with purulent ulcers on the plantar surface of the right foot. Radiograph of the right foot showed soft tissue swelling without evidence of osteomyelitis. Empiric antibiotic treatment with vancomycin was initiated. A wound culture was obtained from the purulent drainage which grew positive for methicillin-resistant (MRSA). On the fourth day of treatment with vancomycin, multiple symmetric, purpuric lesions arose on the patient's trunk and extremities. Skin biopsy with histopathology showed subepidermal acantholysis with neutrophil-predominant inflammatory infiltrate consistent with leukocytoclastic vasculitis. Vancomycin was discontinued and the patient's exanthem began to regress, with full resolution after 30 days post withdrawal of the antibiotic.