Yersinia enterocolitica and Yersinia pseudotuberculosis.

Yersinia enterocolitica can cause enteritis, right lower-quadrant pain mimicking appendicitis, reactive arthritis, and erythema nodosum. This organism is transmitted through food, animal contact, and contaminated blood products. Patients with iron excess are at a higher risk for serious infection. This article describes the history, microbiology, virulence factors, epidemiology, clinical manifestations, diagnosis, and therapy of Y. enterocolitica and Y. pseudotuberculosis. In addition, the immune response of those developing reactive arthritis following infection with Y. enterocolitica is discussed.