Listeria monocytogenesusually causes meningitis or bacteremia, often in immunocompromised adults, pregnant women, or infants. We report a case of septic arthritis caused byL. monocytogenesin a patient with seronegative rheumatoid arthritis (RA) whose hip replacement was infected. She subsequently died, probably secondary to an adult respiratory distress syndrome, a rare complication of listerial infection. We also reviewed all 18 previously reported cases of septic arthritis caused byL. monocytogenes.The frequency of underlying RA, diabetes, neoplastic disease, and immunosuppressive therapy is prominent, as is the concurrent presence of a previous knee or hip replacement. Thus, the simultaneous presence of immune suppression and certain medical disorders or their treatment and a prosthetic joint should alert the clinician to the possibility thatL. monocytogenesis the offending microbial agent. In contrast, in immunocompetent persons the usual Gram-positive cocci such as staphylococci, streptococci, or even pneumococci predominate. Although the outcome of appropriate treatment with penicillin or ampicillin alone (or with an aminoglycoside or trimethoprim/sulfamethoxazole in penicillin-allergic individuals) is usually favorable, complicating medical disorders can lead to death. Cephalosporins are rarely effective antimicrobial agents in patients with listeriosis.