Acute arthropathy in patients with rash diseases: a comparative study.

The aim of this study was to assess the association of acute arthropathy and selected clinical features in patients with acute rash diseases. Serum samples from 1,554 patients were tested for anti-measles, dengue, human parvovirus B19, and rubella virus IgM using enzyme immunoassay. Sera from children, in whom these infections were excluded, were studied for anti-human herpesvirus type 6 IgG antibodies using an indirect immunofluorescence test. Joint complaints occurred in 31.2% of the 862 patients with an etiologic diagnosis and were more frequently seen in adults than in children (OR 8.5). Among the adults, arthropathy prevailed in women compared to men (OR 1.8). Arthropathy was most frequently reported in rubella (41.2%) and in dengue fever cases (41.1%) than in the other rash diseases studied (p < 0.0001). Joint complaints were more frequently seen in patients with fever (OR 1.6) and with five or more days of onset of the disease (OR 1.6), regardless of serological diagnosis. Arthropathy appeared as a frequent condition in rash diseases, typically with low severity and no specific pattern of joint involvement.