Drug associated cutaneous vasculitis in adults in northwestern Spain.

OBJECTIVE

To examine the incidence and clinical features of adults with biopsy proven cutaneous vasculitis (CV) associated with drugs.

METHODS

Retrospective study of an unselected population of adults (age >20 years) with biopsy proven leukocytoclastic CV from 1988 through 1997. Drug associated CV was considered if CV was confirmed by a skin biopsy and there was a history of drug use within one week before the development of CV. Drug associated CV was classified by American College of Rheumatology (ACR) criteria. To differentiate Henoch-Schonlein purpura (HSP) from hypersensitivity vasculitis (HV), the traditional criteria proposed by Michel, et al were used (J. Rheumatol. 1992;19:721-8).

RESULTS

Thirty-three of 138 patients (23.9%) presenting with biopsy proven CV were diagnosed with drug associated CV. The annual incidence rate of biopsy proven drug associated CV in adults was 17.49 cases/million (95% CI 11.53-23.46): men 25.10/million (95% CI 14.85-35.36), women 10.31/million (95% CI 3.92-16.70). Antibiotics (n = 13), especially amoxicillin, and analgesics or nonsteroidal anti-inflammatory drugs (n = 11) were the drugs more commonly associated with CV. All adults with drug associated CV met the ACR classification criteria for HV or HSP. Based on Michel's criteria 26 patients (78.8%) were classified as having HV and 7 HSP. No patient met ACR criteria for other systemic vasculitides. Complete recovery with no sequelae was observed in most cases.

CONCLUSION

Among patients with CV, drug associated disease is common and usually has a good clinical outcome.