Clinical features of patients with novel Yersinia species.

Our purpose was to describe the clinical features of patients with novel Yersinia species. Between 1985 and 1999; 194 patients had yersinia species isolated from stool specimens, 38 (20%) had non-Yersinia enterocolitica species; 12 (32%) had Yersinia intermedia, 7 (18%) Yersinia fredericksenii, 3 (8%) Yersinia kristensenii, and the remaining 16 (42%) were unclassified non-Yersinia enterocolitica species. The most common presenting symptom was diarrhea alone in 10 (26.3%) patients. Symptoms persisted for >1 month in 54% of cases; 21% had symptoms for <1 week; 18 (47%) patients were taking corticosteroids, acid suppressants, and/or antibiotics when Yersinia was isolated. An immunocompromised state was present in 11 (29%) patients. An immunocompromised host and administration of acid suppressants predicted persistence of symptoms for >1 month. Most [27 (71%)] patients received no treatment; 5 (13%) received antibiotics. In conclusion, novel non-Yersinia enterocolitica species, including Yersinia intermedia, Y. fredericksenii, and Y. kristensenii may represent up to 20% of all Yersinia isolates. Diarrhea is the most common symptom.