Brucellosis is a systemic infectious disease frequently associated with osteoarticular involvement. While sacroiliitis is a common manifestation of brucellosis, septic osteoarthritis is less frequent. Here, we report two cases of septic osteoarthritis caused by Brucella melitensis.
Both patients had a history of contact with goats before admission. Upon clinical examination, they showed marked pain and limited movement in the hip. Imaging findings revealed obvious osteonecrosis of the right femoral head. Inflammatory markers, including erythrocyte sedimentation rate and C-reactive protein level, were elevated. The tube agglutination test results of both patients were positive (1:160 and 1:200). Real-time polymerase chain reaction analysis of synovial fluid revealed the presence of B. melitensis. We deduced that septic osteoarthritis could explain these clinical and radiological findings. Both patients were followed-up for 12 months. They returned to their normal routine after completing a standard antibiotic regimen, including doxycycline (100 mg, daily) and rifampicin (600 mg), for 6 weeks.
Brucellar hip arthritis is a serious clinical manifestation of brucellosis, presenting mainly as marked joint pain and limited mobility. It is characterized by joint effusion, synovitis, and soft-tissue swelling on magnetic resonance images. Physicians should consider brucellosis as one of the differential diagnoses of arthritis.