Diagnosing pelvic osteomyelitis in patients with pressure ulcers: a systematic review comparing bone histology with alternative diagnostic modalities

Accurate diagnosis of osteomyelitis underlying pressure ulcers is essential, as overdiagnosis exposes patients to unnecessary and prolonged antibiotic therapy, while failure to diagnose prevents successful treatment. Histopathological examination of bone biopsy specimens is the diagnostic gold standard. Bone biopsy can be an invasive procedure, and, for this reason, other diagnostic modalities are commonly used. However, their accuracy is questioned in literature. This systematic review aims to assess accuracy of various modalities (clinical, microbiological and radiological) for the diagnosis of pelvic osteomyelitis in patients with pressure ulcers as compared to the gold standard. A systematic literature search was conducted in July 2019 using the MEDLINE (Medical Literature Analysis and Retrieval System - MEDLARS - Online) and CINAHL (Cumulative Index to Nursing and Allied Health Literature) databases. The search terms were "decubitus ulcer", "pressure ulcer", "pressure sore", "bedsore" and "osteomyelitis". The inclusion criteria were original full-text articles in English comparing the results of bone histology with those of other diagnostic modalities in adult patients with pelvic pressure ulcers. Six articles were included in the systematic review. Clinical diagnosis was found to be neither specific nor sensitive. Microbiological examination, and in particular cultures of bone biopsy specimens, displayed high sensitivity but low specificity, likely reflecting contamination. Radiological imaging in the form of X-ray and CT (computed tomography) scans displayed high specificity but low sensitivity. MRI (magnetic resonance imaging), bone scanning and indium-labelled scintigraphy displayed high sensitivity but low specificity. Our systematic review did not find any diagnostic method (clinical, microbiological or radiological) to be reliable in the diagnosis of pelvic osteomyelitis associated with pressure ulcers as compared to bone histology.