[Acute osteomyelitis. Clinical, radiological and bacteriological features and outcome]

To compare the clinical, radiological, bacteriological features and outcome of neonatal patients with acute osteomyelitis aged (28 days with those of children aged <= 28 days of age.

A retrospective analysis was performed. The clinical histories of patients aged less than 15 years diagnosed with acute osteomyelitis in a tertiary care hospital were reviewed. Acute osteomyelitis was defined as the association between at least two of the following variables: a) positive blood or biopsy culture; b) purulent bone aspiration; c) clinical features compatible with a diagnosis of acute osteomyelitis; d) radiological features suggestive of acute osteomyelitis, and e) favorable outcome after antibiotic treatment. The patients were divided into two groups: group 1: neonatal patients (aged (28 days) and group 2: children aged <= 28 days. Statistical analysis was performed by the Chi-square test and Student's t-test for categorized and numeric variables, respectively.

Between 1977 and 1999, 45 children aged less than 15 years old were diagnosed with acute osteomyelitis. Of these, 17 patients were neonates (group 1) and 28 patients were aged more than 28 days old (group 2). The male:female ratio was 1.1:1 in group 1 and 3:1 in group 2. The mean age was 17.7 +/- 7.5 days in group 1 and 7.2 +/- 4.3 years in group 2. Metaphysis and tibia were more commonly affected in group 2 (p < 0.05). Epiphysis, arthritis and humerus were more frequently affected in group 1 (p < 0.05). Osteolysis and periosteal reaction predominated in group 1 (p < 0.05). 99mTc Bone scintigraphy and magnetic resonance imaging showed pathological findings in all patients. Blood culture revealed Staphylococcus aureus in 46 % of the patients. Blood and biopsy material cultures were positive in 46 % and 75 %, respectively. Of the 45 patients, outcome was favorable in 37 (82.2 %).

Acute osteomyelitis showed different characteristics in the neonatal and postnatal periods. Bone scintigraphy and magnetic resonance showed high sensitivity. Bacteriology was positive in 50 % of patients.