Bacteremia and polyarticular septic arthritis secondary to Moraxella bovis in a pregnant patient with HIV who injects drugs.

CASE PRESENTATION: We report a rare case of Moraxella bovis bacteremia and polyarticular septic arthritis in a 37-year-old pregnant woman with HIV who injects drugs. Two sets of blood cultures obtained 5 hours apart were positive for gram-negative bacilli, and purulent fluid was present intra-operatively from both her left knee and her right third MCP joints.

DIAGNOSIS: Organism identification using ligation sequencing confirmed both her blood culture and synovial tissue isolates as M. bovis. Her infection was initially treated with third-generation cephalosporins and later changed to moxifloxacin because of a drug reaction; although she defervesced clinically with improvement in her C-reactive protein levels, she died most likely as a result of a non-traumatic fat embolism after an elective cesarean delivery.

DISCUSSION: In contrast to Moraxella catarrhalis, other Moraxella species are rarely associated with disease in human hosts. M. bovis is classically associated with infectious bovine keratoconjunctivitis in cattle; interestingly, our patient denied significant animal exposure. To the authors' knowledge, this is the first case describing infection secondary to M. bovis in an adult host.