A Case of Rat Bite Fever Arthritis

Abstract

Rat bite fever is a rare, systemic illness caused by Streptobacillus moniliformis or Spirillum minus following a rat or other rodent bite. Characteristically, fever develops abruptly with maculopapular skin rash after an incubation period of two to ten days, and asymmetric migrating polyarthritis starts later in up to 50% of patients. The arthritis involves the knees, shoulders, elbows, wrists and hands, which may either be suppurative or non-suppurative. Although most cases seem to resolve spontaneously within two weeks, the mortality in untreated cases is around 10∼15%. The response to antibiotic treatment is good and early diagnosis is the most important prognostic factor. We report a patient who developed arthritis with fever after biting by rat.