Anakinra in a Preterm Infant with Bronchopulmonary Dysplasia: A Case Report

Bronchopulmonary dysplasia (BPD) remains a major complication of extreme prematurity, driven in part by persistent inflammation. Interleukin (IL)-1-mediated signaling plays a central role in sustaining lung injury, making IL-1 blockade a potential therapeutic target. Evidence on the use of anakinra, a recombinant IL-1 receptor antagonist, in neonatal BPD is still limited. We report the case of a female preterm infant (28⁺² weeks' gestation, birth weight 800 g, -1.41 zs) affected by BPD requiring prolonged respiratory support. Due to persistent respiratory failure despite standard therapies, off-label treatment with subcutaneous anakinra (5 mg/kg twice daily) was initiated at 150 days of life. Clinical respiratory parameters and exploratory salivary inflammatory biomarkers (IL-6 and soluble urokinase plasminogen activator receptor, suPAR) were longitudinally monitored. Following anakinra initiation, the patient showed a gradual improvement in respiratory parameters, with reduction in oxygen requirement, mean airway pressure, and improved gas exchange. Respiratory support was gradually de-escalated from nasal intermittent positive pressure ventilation to continuous positive airway pressure and subsequently to high-flow nasal cannula. Salivary suPAR levels demonstrated a decreasing trend, while IL-6 showed transient fluctuations, partly associated with intercurrent infections. Treatment was generally well tolerated during the observation period. The infant was discharged on minimal respiratory support, with continued improvement during follow-up. This case suggests a possible role of IL-1 blockade in the modulation of persistent inflammation in BPD with a refractory clinical course, although the observed clinical course may also reflect the natural evolution of the disease. Longitudinal salivary biomarkers may represent a feasible, exploratory, non-invasive approach to describe inflammatory dynamics over time. Larger prospective studies are needed to evaluate the efficacy, safety, and optimal treatment protocols of anakinra.