Osteomyelitis in sickle cell disease: You know it when you see it?

BACKGROUND: Children with sickle cell disease (SCD) are at increased risk for bacterial infections including osteomyelitis (OM). Fever and bone pain, key presenting symptoms of OM, are common in SCD, thus complicating diagnosis. We reviewed presentation, imaging features, and microbiologic etiologies of children with SCD treated for OM. METHODS: The comprehensive SCD clinical database of children and adolescents with SCD followed at a single, large tertiary pediatric center was searched to identify all diagnostic coding for potential cases of osteomyelitis in children ages 6 months to 21 years from 2010 – 2019. Medical charts were reviewed to determine OM diagnostic probability based on radiographic and microbiologic findings and the duration of prescribed antibiotic treatment for OM. RESULTS: Review of 3,553 patients (18,039 person-years) identified 20 episodes of probable OM in 19 children. Magnetic resonance imaging (MRI) findings to support OM were definitive in 4/19 (21%), probable in 10/19 (53%), suspected in 5/19 (26%), based on blinded radiologist review. Blood and/or operative cultures from bone and tissue debridement isolated Salmonella species in 7 (35%) cases and Methicillin-susceptible Staphylococcus aureus (MSSA) in 2 (10%). Six patients received antibiotic treatment prior to obtainment of cultures. Of culture-positive cases, MRI findings for OM were definitive or probable in 6/9 (67%), suspected in 3/9 (33%). CONCLUSIONS: Distinction between OM and sickle-related bone infarct or vaso-occlusion is difficult based on imaging findings alone. Early attainment of blood and operative cultures increases the likelihood of identifying and adequately treating OM.