Clinical Characteristics of Acute Hematogenous Osteomyelitis With and Without Subperiosteal Abscesses in the Acute Care Setting

Acute hematogenous osteomyelitis (AHO) is a common pediatric disease that can progress to involve nearby structures leading to complications including subperiosteal abscesses (SPAs). Those with SPAs, in particular, often require surgical intervention for complete treatment. Staphylococcus aureus remains one of the most common causes of AHO. With the emergence of community-associated methicillin-resistant Ataphylococcus aureus and its propensity to form abscesses, there has been an observed increased frequency of AHO with SPAs in children. Although magnetic resonance imaging (MRI) remains the gold standard of imaging for AHO, it is not readily available on a 24/7 basis and often necessitates procedural sedation in children. Delay in MRI and surgical intervention in patients with SPAs may lead to increased complications. The goal of this study is to identify, using clinical features easily obtained in the acute care setting, patients at high risk for AHO with SPAs who may benefit from emergent MRI and/or surgical intervention.

A retrospective chart review of patients aged birth to younger than 18 years diagnosed with AHO, who presented to a tertiary pediatric hospital from June 10, 2012, to November 1, 2017, were evaluated. Demographic, clinical, laboratory, and imaging data were collected. Patients were divided into 2 groups: AHO alone and AHO with SPAs.

A final cohort of 110 subjects were included and analyzed. Of these, 73 (66%) were identified as having AHO alone and 37 (33.6%) as having AHO with SPAs. Patients had a higher risk of AHO with SPAs if they had a history of fever, decreased range of motion, edema, or elevated laboratory studies including white blood cell, absolute neutrophil count, erythrocyte sedimentation rate, and C-reactive protein. C-reactive protein was shown to have the highest correlation of AHO with SPAs, with an optimal cut point of 10.3 mg/dL, yielding a sensitivity of 67.7% and specificity of 77.6%. Patients with AHO with SPAs were at higher risk of having a positive blood culture for methicillin-resistant Staphylococcus aureus.

Clinicians in acute care settings should have a high index of suspicion of AHO with SPAs in children with history of fever, decreased range of motion, or elevated laboratory values (white blood cell, absolute neutrophil count, erythrocyte sedimentation rate, and C-reactive protein). In particular, those with a significantly elevated CRP are at a higher risk for having AHO with SPAs in comparison with an uncomplicated AHO. However, with the significant overlap in historical and clinical variables in the initial presentations of children with AHO with and without SPAs, the clinical urgency in obtaining a magnetic resonance imaging must continue to be individualized based on overall clinical suspicion and availability of resources.