302 - Pathogen Identification and Associated Characteristics in a Cohort of Pediatric Acute Hematogenous Osteomyelitis Patients

Poster Number: 302
Publication Number: 302.114

Madison Enderle, George Washington University Milken Institute School of Public Health, Arlington, VA, United States; Gina Gallizzi, Children's National Health System, Washington, DC, United States; Nina R. Hu, George Washington University School of Medicine and Health Sciences, Arlington, VA, United States; Alexandra B. Yonts, Children's National, Washington, DC, United States; Benjamin D. Martin, Children's National Health System, Washington, DC, United States; Rana F. Hamdy, Children's National Health System, Washingtotn, DC, United States

Background: Incidence estimates of pediatric acute hematogenous osteomyelitis (AHO) range from about 2-13 per 100,000 children in developed countries. Blood cultures identify the causative pathogen in approximately 33% of cases, optimizing antibiotic treatment. Bone cultures increase the yield of positive cultures but require an invasive procedure. Recent consensus guidelines recommend bone biopsies for children with AHO when feasible; however, whether the clinical benefit of identifying a pathogen to target the therapy outweighs the risk of undergoing an invasive procedure remains unknown.

Objective: To describe the microbial etiology of the cohort and to describe baseline characteristics, treatment, and outcomes of patients with and without identified pathogens.

Design/Methods: Data were retrospectively abstracted from medical records of patients under age 21 with a clinician’s diagnosis of AHO admitted to Children’s National Hospital from January 2010 – August 2021. Patients with infections of bones of the head, hardware at the site, recent orthopedic surgery, sickle cell disease, or who were immunocompromised were excluded. Bivariate analyses assessed differences between patients with identified pathogens and patients without identified pathogens.

Results: 257 patients were included. 60.7% had identified pathogens. S. aureus was the most commonly identified pathogen (89.3%) with methicillin-resistant S. aureus accounting for 25.8% of the total. Overall, 5.8% of identified pathogens were resistant to the administered empiric therapy. The mean age of the cohort was 7.11 years (SD = 4.89) and was not statistically different between those with pathogens identified and those without pathogens identified. Peak CRP, number of cultures, number of lab draws, number of surgeries, length of hospital stay, number of antibiotics, and length of intravenous therapy were statistically significantly higher among those with pathogens identified than those without pathogens identified (p < 0.01 for all). Readmission (p = 0.41), and recurrence of infection (p = 0.93) did not differ between the two groups.Conclusion(s): Those without pathogens identified did not experience more diagnostic tests or longer treatment than those with pathogens identified. Additionally, readmission and recurrence of infection were similar. However, those without pathogens identified experienced less severe disease; thus, further study is required to determine if the associations remain after adjusting for severity.
Figure 1. Culture results of a retrospective cohort of CNH AHO patients
Table 1. Baseline and treatment characteristics and outcomes of a retrospective cohort of CNH AHO patients stratified by pathogen identification.