A 43-year-old man hospitalized for hepatocellular carcinoma complicati
ng alcoholic cirrhosis developed septic arthritis of the right knee du
e to Brucella. There was no history of exposure to potentially infecte
d animals or of a high-risk occupation. The patient occasionally ate f
arm-produced goat cheese. He had immune depression as a result of his
cancer. Monoarthritis due to Brucella is infrequent. Diagnosis rests o
n serological and bacteriological tests. Prolonged administration of a
ntimicrobials with activity on intracellular organisms is required.