Blastomycosis of bones and joints.

A retrospective study of 45 patients hospitalized with blastomycosis of bones or joints revealed 41 cases of osteomyelitis and 12 cases of septic arthritis. The majority were men (35 [78%] patients) and non-Aboriginal (32 [71%] patients). Median time from the onset of symptoms to hospitalization was shorter in women than men (male, 48 d; female, 14 d; P < 0.02), and shorter for Aboriginals than non-Aboriginals (non-Aboriginal, 50 d; Aboriginal, 19 d; P < 0.04). Cutaneous disease was present in 33 (73%) patients, and lung involvement was present in 29 (64%) patients. The most common osseous sites of involvement were the lower limb and axial skeleton. Common orthopaedic symptoms of bone lesions included bone pain in 42 (78%) patients, swelling in 32 (59%) patients, and soft tissue abscesses in 21 (39%) patients. Joint infection (12 patients) manifested as a monoarticular arthropathy presenting with effusion in 9 (75%) patients, pain in 8 (67%) patients, and decreased range of motion in 5 (42%) patients. Osseous blastomycosis can mimic bacterial infection and should be included in the differential diagnosis of bone and joint infection in patients who have visited or who live in geographic regions where B dermatitidis is endemic.