The accuracy of different imaging techniques in diagnosis of acute hematogenous osteomyelitis.

OBJECTIVE: The aim of this study was to establish and compare diagnostic accuracy (sensitivity, specificity, and diagnostic odds ratio) of plain x-ray, ultrasonography, bone scintigraphy, computed tomography (CT), and magnetic resonance imaging (MRI) in pediatric acute hematogenous osteomyelitis.

MATERIAL AND METHODS: Analysis of patients' data, hospitalized at the Department of Pediatric Surgery with suspected acute hematogenous osteomyelitis in the period of 2002-2008, was carried out prospectively. Inclusion criteria were age of 1-18 years, pain in bone area, fever, functional disorder, and (or) signs of infection. Plain x-ray, ultrasonography, bone scintigraphy, computed tomography, and magnetic resonance imaging were performed. The recommendations of Standards for Reporting of Diagnostic Accuracy were used in study design.

RESULTS: A total of 183 patients were included into the study. Acute hematogenous osteomyelitis was diagnosed in 156 (85%) patients, and 27 (15%) had other diseases. A total of 169 early plain x-rays (median on the first day of hospital stay), 142 late x-rays (15th day of hospital stay), 82 ultrasonographies (second day), 76 bone scintigraphy (third day), 38 MRI scans (seventh day), and 17 CT (15th day) were performed. The sensitivity of ultrasonography was 0.55 (95% CI, 0.43-0.67); specificity, 0.47 (95% CI, 0.24-0.7); and diagnostic odds ratio, 1.08 (95% CI, 0.3-3.84). The sensitivity of CT was 0.67 (95% CI, 0.38-0.88); specificity, 0.5 (95% CI, 0.01-0.98); and diagnostic odds ratio, 2.0 (95% CI, 0.02-172.4). The sensitivity of early x-ray was 0.16 (95% CI 0.1-0.23); specificity, 0.96 (95% CI, 0.78-1.0); and diagnostic odds ratio, 4.34 (95% CI, 0.63-186.3). The sensitivity of MRI was 0.81 (95% CI, 0.64-0.93); specificity, 0.67 (95% CI, 0.22-0.96); and diagnostic odds ratio, 8.67 (95% CI, 0.91-108.5). The sensitivity of late x-ray was 0.82 (95% CI, 0.75-0.88); specificity, 0.92 (95% CI, 0.62-1.0); and diagnostic odds ratio, 51.17 (95% CI, 6.61-2222.0). The sensitivity of bone scintigraphy was 0.81 (95% CI, 0.68-0.90); specificity, 0.84 (95% CI, 0.60-0.97); and diagnostic odds ratio, 22.30 (95% CI, 4.9-132.7).

CONCLUSIONS: Our analysis showed that late x-ray is the most valuable radiologic method in the diagnosis of acute hematogenous osteomyelitis, but bone scintigraphy and magnetic resonance imaging are the most valuable tests at the onset of the disease.