Early Bone Ischemia in Pediatric Acute Hematogenous Osteomyelitis and its Association With Progression to Chronic Osteomyelitis: New Insights From Gadolinium-enhanced Subtraction MRI

Background: Acute hematogenous osteomyelitis (AHO), the most common osteoarticular infection in children, carries a significant risk for chronic complications. Predicting chronic complications early in the course of disease is challenging. The underlying pathogenesis of complications is not fully understood. Methods: Children who presented to Sultan Qaboos University Hospital, Muscat, Oman between January 2015 and April 2022 for AHO were identified by a search of magnetic resonance imaging (MRI) records. Children between 1 month and 18 years of age who did not meet exclusion criteria, and whose MRI also included gadolinium-enhanced subtraction (GES) sequences were included in the analysis. Outcomes were compared between patients who showed early evidence of bone ischemia and those who did not. Results: The analysis included 11 children who had GES MRI sequences from among 18 AHO cases in total. Median age was 5 years (IQR, 4–9), and 82% were males. Median duration of symptoms at presentation was 5 days (IQR, 3–7). GES sequences showed early bone ischemia in 6 of 11 (55%) patients. Patients with early bone ischemia were treated with significantly longer durations of IV antibiotics (median 23 vs. 10 days, P = 0.017) and oral antibiotics (median 134 vs. 29 days, P = 0.004), and required more surgical debridements (median 3 vs. 0 debridements, P = 0.017). Chronic osteomyelitis only developed among patients with early bone ischemia (5/6 vs. 0/5, P = 0.015). Conclusions: In pediatric AHO, GES MRI sequences revealed early bone ischemia in a significant proportion of patients. Early bone ischemia was strongly associated with progression to chronic osteomyelitis.