Clinical Epidemiology and Outcomes of Pediatric Musculoskeletal Infections

Objectives To understand the epidemiology of acute hematogenous osteomyelitis and septic arthritis, including clinical and demographic features, microbiology, treatment approaches, treatment-associated complications, and outcomes. Study design Retrospective cohort study of 453 children with acute hematogenous osteomyelitis and/or septic arthritis from 2009 to 2015. Results Among the 453 patients, 218 (48%) had acute hematogenous osteomyelitis, 132 (29%) had septic arthritis, and 103 (23%) had concurrent acute hematogenous osteomyelitis/septic arthritis. Treatment failure/recurrent infection occurred in 41 patients (9%). Patients with concurrent acute hematogenous osteomyelitis/septic arthritis had longer hospital stays, longer duration of antibiotic therapy, and were more likely to have prolonged bacteremia and require intensive care. Staphylococcus aureus was identified in 228 (51%) patients, of which 114 (50%) were methicillin-resistant S aureus. Compared with septic arthritis, acute hematogenous osteomyelitis and concurrent acute hematogenous osteomyelitis/septic arthritis were associated with higher odds of treatment failure (OR, 8.19; 95% CI, 2.02-33.21 [P=.003]; and OR, 14.43; 95% CI, 3.39-61.37 [P<.001], respectively). The need for more than 1 surgical procedure was also associated with higher odds of treatment failure (OR, 2.98; 95% CI, 1.18-7.52; P=.021). Early change to oral antibiotic therapy was not associated with treatment failure (OR, 0.64; 95% CI, 0.24-1.74; P=.386). Most (73%) medically attended treatment complications occurred while on parenteral therapy. Conclusions Musculoskeletal infections are challenging pediatric infections. S aureus remains the most common pathogen, with methicillin-resistant S aureus accounting for 25% of all cases. Concurrent acute hematogenous osteomyelitis/septic arthritis is associated with more severe disease and worse outcomes. Fewer treatmentrelated complications occurred while on oral therapy. Early transition to oral therapy was not associated with treatment failure.