Prosthetic joint infection with Pasturella multocida following cat scratch: a report of 2 cases.

Infection is a known cause of failure in a total joint arthroplasty. Secondary or delayed infections are caused by a wider variety of pathogens, including Gram-negative organisms. Pasturella multocida is a Gram-negative bacillus that forms part of the normal nasopharyngeal and gastrointestinal flora of cats and many other animals. Nontrauma-associated infections also have been reported, but these are more often confined to animal handlers. We report 2 patients who had cat scratch and who developed infection of their total hip arthroplasties with P multocida. Both patients were immunocompromised and required revision of their hip arthroplasty. One patient had 1-stage revision, because infective cause was not obvious at the time of surgery. These patients were followed for 18 months to 2 years after surgery, with good results.