RESUMO
BACKGROUND: IgA vasculitis (IgAV) is assumed to be uncommon in adults. OBJECTIVES: To determine the incidence rate of histologically proven IgAV in the adult Slovenian population. METHODS: A retrospective chart review of adult patients diagnosed with IgAV was performed at the departments of rheumatology, nephrology, infectious diseases and dermatovenereology at an integrated secondary/tertiary university teaching hospital. In order to avoid missing miscoded cases, the Institute of Pathology, University of Ljubljana, Slovenia, provided a list of all patients with an IgAV-compatible histological pattern on biopsy. The annual incidence rate of histologically proven IgAV was calculated. RESULTS: Eighty-one new cases of IgAV were identified from June 2010 to June 2013. The estimated annual incidence rate of IgAV was 5·1 per 100,000 adults [95% confidence interval (CI) 3·4-7·4]; in men it was 6·1 per 100,000 (95% CI 3·9-10·6) and in women it was 3·7 per 100,000 (95% CI 1·8-6·8). CONCLUSIONS: Although we only included histologically proven cases of IgAV, the annual incidence rate of 5·1 per 100,000 adults is 3-6-times higher than previously reported.