Acute Osteomyelitis: A Retrospective Study

Background: Acute osteomyelitis(AO) is a rare but serious infection in children, as it can cause significant morbidity.

Objective: Characterization of children with AO in a suburban area outside Lisbon.

Methods: Retrospective study of children (<18years) hospitalized for AO between 2012 and 2018. Record data: demographic, clinical, laboratory, imagiologic and therapeutic information. Statistical analysis performed with IBM-SPSS®.

Results: 40 children were included, the majority male (60%) and of African origin (63%) with mean age of 7.9±5.4years.

Lower limb was the most affected (75%), with predominance of femur (35%). Concomitant septic arthritis was present in 28%, being coxofemoral the most affected joint.

Main symptoms at presentation were pain at mobilization (90%), spontaneous pain (85%), fever (60%) and local inflammatory signs (55%), with median duration before admission of 2.0days (IQR 1.0-6.0). 45% had leukocytosis, 3% leukopenia, 79% elevated erythrocyte sedimentation rate(>20mm/h) and 58% elevated C-reactive protein(>2mg/dL).

53% had risk factors: sickle-cell disease (43%), acute mastoiditis (5%), smallpox (2.5%) and preceding fracture (2.5%).

Agent identified in 18 (45%): S. aureus 7 (MSSA 5, MRSA 2), Streptococcus pneumoniae 3, Escherichia coli 3, Streptococcus pyogenes 2, Neisseria meningitidis 1, Mycobacterium bovis 1, Candida famata 1. Methods: culture media (89%) and detection of bacterial DNA by PCR (11%).

Magnetic resonance(MRI) was performed in 95%. In all, signs of OA were present.

All were treated with antibiotics with median duration of 6.1weeks (IQR 6.0-8.6). Mycobacterium bovis infection was treated with anti-tuberculosis drugs and fungal infection with antibiotics and antifungal drugs. 35% needed surgery and 8% hyperbaric oxygen therapy.

There were 11 complications: subperiosteal abscess (n=6;15%), deep soft tissue abscess (n=1;3%), venous thrombosis (n=4;10%).

Conclusion: We found a high prevalence of african children and sickle-cell disease. In a child with fever and bone pain, especially if elevation of acute phase reactants, we should consider OA and perform a MRI.