The Spectrum of Pediatric Osteoarticular Infections: A Comparative Study

BACKGROUND: There is a paucity of data relating to pediatric subacute or chronic hematogenous osteomyelitis (SCHO), non-hematogenous osteoarticular infections (NHO), and osteoarticular hardware infections (HI). A comparative analysis of the entire spectrum of pediatric osteoarticular infections was conducted to identify distinguishing clinical features and biological markers. METHODS: Using ICD9/10 code searches, we identified pediatric patients ≤18 years of age at Hasbro Children’s Hospital (2006–2016) and Nationwide Children’s Hospital (2015–2016) with osteoarticular infections. Cases of Lyme arthritis or ENT-related infections were excluded. Eligibility criteria were confirmed by reviewing medical records and clinical and laboratory data were collected systematically. RESULTS: 428 children met inclusion criteria: 211 (49%) had acute hematogenous osteomyelitis (AHO), 61 (14%) suppurative arthritis (SA), 42 (10%) SCHO, 60 (14%) NHO, and 54 (13%) HI. The age distribution differed significantly across the five infection types: AHO (median, 9.2 years), SA (5.0), SCHO (10.2), NHO (11.5), and HI (14.5); P < 0.001. Median initial CRP values were significantly higher (P < 0.001) in AHO (65 mg/dl) and SA (44) compared with SCHO (15), NHO (15) and HI (24). An ESR >19 mm/hours at presentation was more sensitive than a CRP >8.0 mg/dl in identifying SCHO (80% vs. 64%; P = 0.035). Bacteremia occurred more frequently in AHO (42%) and SA (25%) compared with SCHO (7%), NHOI (5%) and OHI (4%); P < 0.001. Patients with HI had significantly more complications as reflected by more ICU admissions (33% vs. ≤3% for other groups), and longer antibiotic treatment durations (median, 65 vs. ≤37 days for other groups); P < 0.001 for each comparison. S. aureus was the most common organism isolated for all infections, but the proportion of other Gram- and Gram-negative pathogens was significantly higher in SCHO, NHO, and HI compared with AHO and SA (P < 0.001). The ratio of MSSA to MRSA among isolates was 3:1, and did not differ significantly across the infection types. CONCLUSION: SCHO, NHO, and HI commonly present with minimal evidence of inflammation, and differ in the spectrum of causative pathogens compared with AHO and SA. Further studies are required to optimize the diagnosis and management of non-acute, non-hematogenous osteoarticular infections. DISCLOSURES: All authors: No reported disclosures.