Dimorphic fungal osteoarticular infections

The objective of this investigation was to review the clinical manifestations, management, and outcome of osteoarticular infections caused by dimorphic fungi. We exhaustively reviewed reports of bone and joint infections caused by dimorphic fungi published between 1970 and 2012. Underlying conditions, microbiological features, histological characteristics, clinical manifestations, antifungal therapy, and outcome were analyzed in 222 evaluable cases. Among 222 proven cases (median age 41 years [interquartile range (IQR) 26-57]), 73 % had no predisposing condition. Histopathology performed in 128 (57 %) cases and culture in 170 confirmed diagnosis in 63 % and 98 % of the cases, respectively. Diagnosis was obtained from an extra-osteoarticular site in 16 cases. The median diagnostic time was 175 days (IQR 60-365). Sporothrix schenckii was the most frequent pathogen (n = 84), followed by Coccidioides immitis (n = 47), Blastomyces dermatitidis (n = 44), Histoplasma capsulatum (n = 18), Paracoccidioides brasiliensis (n = 16), and Penicillium marneffei (n = 13). Arthritis occurred in 87 (58 %) cases and osteomyelitis in 64 (42 %), including 19 vertebral osteomyelitis. Dissemination was reported in 123 (55 %) cases. Systemic antifungal agents were used in 216 (97 %) patients and in combination with surgery in 129 (60 %). Following the Infectious Diseases Society of America (IDSA) guidelines, a successful initial medical strategy was observed in 97/116 (84 %) evaluable cases. The overall mortality was 6 %, and was highest for P. marneffei (38.5 %). This study demonstrates that dimorphic osteoarticular infections have distinctive clinical presentations, occur predominantly in apparently immunocompetent patients, develop often during disseminated disease, and may require surgical intervention.