Poncet's disease: tuberculous rheumatism.

Poncet's disease is characterized by a polyarthritis that occurs during acute tuberculosis infection in which no mycobacterial involvement can be found or other known cause of polyarthritis detected. It is a different entity from tuberculous arthritis, which is usually monoarticular and is caused by direct tuberculin infection. Poncet's disease remains a diagnosis of exclusion. Thirteen cases have been reported in the English-language literature since 1974. All patients who received the Mantoux test reacted positively, and 10 of 11 patients treated with antituberculous drugs had resolution of arthritis on therapy. Poncet's disease and erythema nodosum could be differing expressions of a common immunopathogenic response to tuberculin.