Association between plasma surfactant proteins A and D levels and types of respiratory therapy in preterm neonates

Surfactant proteins A (SP-A) and D (SP-D) are key components of the pulmonary surfactant system and play important roles in lung immunity and homeostasis. Their plasma levels may reflect pulmonary maturity and disease severity in preterm neonates. Aim: to evaluate the association between plasma levels of SP-A and SP-D and the type of respiratory therapy administered to preterm neonates. Material and methods. A total of 114 preterm neonates treated in multiple neonatal intensive care units (NICUs) were categorized based on initial respiratory support - non-invasive (e.g., CPAP, NIPPV) or invasive ventilation. Plasma SP-A and SP-D levels were measured using ELISA. The statistical analysis was performed to assess correlations with therapy type, diagnosis, and outcomes. Results. Of the neonates initially managed with non-invasive therapy, 60.6% required escalation to invasive ventilation. Plasma SP-A and SP-D levels were significantly higher in those requiring invasive support compared to those maintained on non-invasive therapy. Repeated surfactant dosing and lower APGAR scores were also associated with elevated protein levels and escalation therapy. Although trends were observed in the group initially receiving invasive ventilation, statistical significance was limited by the small sample size. Conclusion. Elevated plasma SP-A and SP-D levels are associated with an increased need for invasive respiratory support in preterm neonates. These proteins may serve as useful biomarkers for predicting respiratory therapy needs and monitoring treatment responses. Further large-scale studies are needed to validate their clinical utility. The research was carried out in accordance with the principles of the Declaration of Helsinki. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.