Aspergillus osteomyelitis: epidemiology, clinical manifestations, management, and outcome

Abstract

Background: The epidemiology, pathogenesis, diagnosis, and management of Aspergillus osteomyelitis are not well understood.

Methods: Protocol-defined cases of Aspergillus osteomyelitis published in the English literature were reviewed for comorbidities, microbiology, mechanisms of infection, clinical manifestations, radiological findings, inflammatory biomarkers, antifungal therapy, and outcome.

Results: Among 180 evaluable patients, 127 (71%) were males. Possible predisposing medical conditions in 103 (57%) included pharmacological immunosuppression, primary immunodeficiency, and neutropenia. Seventy-three others (41%) had prior open fracture, trauma or surgery. Eighty (44%) followed a hematogenous mechanism, 58 (32%) contiguous infections, and 42 (23%) direct inoculation. Aspergillus osteomyelitis was the first manifestation of aspergillosis in 77%. Pain and tenderness were present in 80%. The most frequently infected sites were vertebrae (46%), cranium (23%), ribs (16%), and long bones (13%). Patients with vertebral Aspergillus osteomyelitis had more previous orthopedic surgery (19% vs 0%; P = 0.02), while those with cranial osteomyelitis had more diabetes mellitus (32% vs 8%; P = 0.002) and prior head/neck surgery (12% vs 0%; P = 0.02). Radiologic findings included osteolysis, soft-tissue extension, and uptake on T2-weighted images. Vertebral body Aspergillus osteomyelitis was complicated by spinal-cord compression in 47% and neurological deficits in 41%. Forty-four patients (24%) received only antifungal therapy, while 121 (67%) were managed with surgery and antifungal therapy. Overall mortality was 25%. Median duration of therapy was 90 days (range, 10-772 days). There were fewer relapses in patients managed with surgery plus antifungal therapy in comparison to those managed with antifungal therapy alone (8% vs 30%; P = 0.006).

Conclusions: Aspergillus osteomyelitis is a debilitating infection affecting both immunocompromised and immunocompetent patients. The most common sites are vertebrae, ribs, and cranium. Based upon this comprehensive review, management of Aspergillus osteomyelitis optimally includes antifungal therapy and selective surgery to avoid relapse and to achieve a complete response.

Keywords: Aspergillus; Osteomyelitis.