Optimizing Pediatric Septic Arthritis Management: A Retrospective Review Following Updated Guidelines

Abstract

Kathryn Timberlake, PharmD, kathryn.timberlake@sickkids.ca None. The authors declare no conflicts of interest. Septic arthritis is a bacterial infection of the synovial fluid of a joint often requiring urgent intervention to prevent long-term morbidity. In 2024, an IDSA guideline was published suggesting a total duration of 10 to 14 days of combined parenteral and oral treatment can be recommended, rather than longer courses of 3 to 6 weeks. This study describes a single-centre retrospective review of pathogen distribution, antimicrobial selection, and treatment duration in pediatric patients with septic arthritis and evaluates alignment with new guidelines. A retrospective review was conducted at a quaternary pediatric hospital of patients diagnosed with septic arthritis from January 2019 and December 2024. Patients with osteomyelitis co-infection, hardware-associated infections, malignancy, or significant medical complexity were excluded. Demographics, infection site, microbiology, antimicrobial regimens, treatment duration, and infectious diseases (ID) consultation data were collected and analyzed descriptively. Of 71 identified patients, 35 met inclusion criteria. The knee was the most commonly affected joint (49%), followed by the hip (34%), elbow (14%), and shoulder (3%). Staphylococcus aureus was the most frequently isolated organism (n=17), followed by Group A Streptococcus (n=7). Of 17 patients with Staphylococcus aureus (MSSA), preferred parenteral therapy was used in 13 (76%). The total duration of antimicrobial therapy ranged from 9 to 80 days, with a mean of 33 days. An ID consultation was obtained in 32 of 35 patients, with most recommendations followed; however, several patients received therapy exceeding recommended durations. Treatment length in this cohort was longer than suggested in updated guidelines. In this pediatric septic arthritis cohort, antimicrobial therapy durations frequently exceeded contemporary guideline recommendations despite high rates of ID consultation and preferred antibiotic therapy selection. These findings highlight an opportunity to optimize treatment duration and support antimicrobial stewardship initiatives aimed at reducing unnecessary prolonged antibiotic exposure.