Seal finger in a wildlife ranger.

We describe a case of septic arthritis of the interphalangeal joint of the thumb in a man following a seal bite. Early and continued treatment with antibiotics of the penicillin family failed to control the infection. Empirical treatment with tetracycline resolved the infection, but the patient has permanent joint damage. In apparently ordinary infective conditions, which fail to respond to therapy, the history may suggest that an unusual organism is responsible.