Rheumatic fever and Yersinia arthritis. Criteria and diagnostic problems in a changing disease pattern.

A study of rheumatic fever (RF) in Finland and Sweden was carried out by examining (a) the patients with RF in two hospitals in Helsinki, Finland during the years 1969-72, (b) the case reports of RF patients in Uppsals hospital region (UHR) in Sweden during the years 1968-69. In Helsinki there were 22 and 2n UHR 16 patients with an acceptably certain diagnosis of RF. Of the five "major manifestations" according to Jones' revised criteria (Circulation, 32: 664, 1965), carditis and polyarthritis were the most valuable diagnostic criteria, whereas only 8 cases of the whole material had erythema marginatum. The two remaining criteria, chorea and subcutaneous nodules, have lost their diagnostic value, since they are extremely rare nowadays. The diagnosis of RF was substantially influenced by arthritis associated with Yersinia enterocolitica infection. Some of the patients with YA met completely the Jones revised criteria for the diagnosis of RF. The symptomatology of Yersinia arthritis (YA) and that of RF are similar in some cases it is impossible to separate then even on the basis of serological tests. Diagnostic criteria should therefore be viewed against the geographical distribution of the disease. In addition to the required Jones' criteria, we concluded that at least in Sweden and Finland, in order to be categorized under RF, a patient must demonstrate clinical and serological evidence of acute streptococcal infection and, furthermore, Yersinia infection must be excluded.