Graft infection and bacteremia with a tolerant L-form of Streptococcus sanguis in a patient receiving hemodialysis.

I report a case of a tolerant L-form Streptococcus sanguis infection involving an artificial vascular access site that was probably acquired from a nonhuman source; this is the first report of such an infection in a human. Gram stains from the infected access site and blood cultures revealed an aberrant form which could only be recovered by passage through hypertonic sucrose media before being reisolated and subsequently identified as S. sanguis. The same organism was isolated from a pet dog of the patient. The organism was also felt to be tolerant to penicillin. The patient was successfully treated by removal of the artificial graft and intravenous erythromycin therapy. Microorganisms acquired from nonhuman sources are potential pathogens in the immunocompromised patient.