Yersinia enterocolitica: an inducer of chronic inflammation.

The aim of the present study was to elucidate the connection between yersiniosis and chronic inflammation. During the period 1974-83, Yersinia enterocolitica infection was diagnosed in 458 hospitalized patients by antibody response, or isolation. The patients were followed for 4-14 years (1987); 160 were readmitted with chronic disease. Fifty-three patients had persistent joint complaints, 18 developed ankylosing spondylitis, 14 rheumatoid arthritis, and 17 iridocyclitis. Thirty-eight patients suffered from chronic abdominal pain, and another 28 from chronic diarrhoea. Two who underwent proctocolectomy microscopically had ulcerative colitis. Eleven patients developed neurological disease; others developed conditions such as chronic nephritis, thyroid disease, insulin-dependent diabetes, etc. Chronic hepatitis, found in 22 patients, was significantly correlated with positive test for antinuclear antibody and rheumatoid factor, and with death. Several patients developed chronic multiorgan disease, probably with chronic hepatitis as pivot. Regarding the whole material, the difference between observed and expected cumulative survival rates remained significant for 8 years (0.9189 < 0.9456; p < 0.025), indicating a substantial impact on long-term survival exerted by chronic yersiniosis.