Drug-Induced Vasculitis

Abstract

Drug-induced vasculitis is defined as inflammation of blood vessels due to an adverse effect of a drug. Histologically, vasculitis is defined as an inflammatory cell-mediated infiltration and destruction of blood vessels. Vasculitis can be either primary, as seen in granulomatous polyangiits, or secondary, when associated with drugs, infection, malignancy, or connective tissue disease.

While the exact pathogenesis of drug-induced vasculitis remains unclear, it is strongly believed to be an immune-complex mediated process. Many drugs are associated with vasculitis and nearly every class of drug has been implicated. The most common drugs associated with vasculitis are propylthioruacil, hydralazine, minocycline, allopurinol, D-penicillamine, sulfasalazine, penicillins, cephalosporins and several immunomodulating agents, discussed below. Diagnosis of drug-induced vasculitis is often challenging, as there are no pathognomonic clinical or histological features to distinguish it from other causes of vasculitis. It is also very difficult to prove that an exposure to a drug led to cutaneous vasculitis. Severity of drug-induced vasculitis can range from mild, and self-limiting to severely progressive and even fatal. A high index of suspicion should be maintained for vasculitic lesions that arise in the setting of recent introduction of a new drug. Suspicious agents should be promptly withdrawn, as resolution often occurs soon after discontinuation of the offending drug.