Anakinra for infants under six months with Kawasaki disease and coronary artery lesions: a multicenter case series and literature review

Infants with Kawasaki Disease (KD) have a higher risk of incomplete presentations, IVIG resistance, and coronary artery lesions (CALs). IL-1 plays a key role in the pathogenesis, highlighting its potential as a therapeutic target. To report a multicenter Italian experience and review the literature on anakinra use in KD infants with CALs. We retrospectively reviewed charts of patients aged ≤ 6 months treated with anakinra at four Italian centers between 2015 and 2024. A systematic Literature search was also conducted in PubMed, Scopus, Embase, and the Cochrane Library up to October 2024. Eight infants were included. The median age at diagnosis was 2.75 months. Six had incomplete KD. All were resistant to first-line treatment and all developed CALs, which were detected at a median of 9.5 days from fever onset. Anakinra was initiated at a median of 18 days from fever onset and 1.5 days after CALs detection. One patient received only subcutaneous anakinra. Seven infants underwent intravenous administration (median dose 8.5 mg/kg/day), four of whom received an initial bolus (median dose 2.75 mg/kg), and six were subsequently switched to subcutaneous dosing. Median total treatment duration was 22.5 days. CALs completely resolved in five patients, and improved in two. One treatment-related adverse event was reported. The literature review identified nine additional infants ≤ 6 months; seven showed systemic improvement and five had coronary improvement, and no adverse events were reported after anakinra treatment. Anakinra may be a promising and well-tolerated option for infants with KD and CALs, especially in IVIG-resistant or high-risk cases. While adverse events were unusual, further studies are needed to confirm its safety and efficacy. • This is the first multicenter Italian experience combined with a focused literature review on the use of anakinra in children aged ≤6 months. It offers an overview of current practices, emphasizing key aspects such as timing, dosing strategies, routes of administration, and treatment duration to optimize clinical outcomes. • Anakinra emerges as a safe and effective treatment option for IVIG-resistant infants with Kawasaki Disease and coronary artery lesions. Early anakinra intravenous administration ensures rapid control of inflammation and improves patient comfort. • The findings support the potential integration of IL-1 blockade into the treatment algorithm for infants with Kawasaki Disease, paving the way for future prospective studies. These will be essential to confirm these observations and establish standardized treatment protocols for this high-risk population.