Background. The present study investigates the serum soluble receptor for advanced glycation end products (sRAGE) in serum as a marker of a number of lung diseases as well as asthma and bronchiolitis. The aim was to find a pattern with the severity, frequency of wheezing episodes, and lung ultrasound findings.

Methods. Fifty-eight infants with a mean age of 11.4±6 (1 - 23) months, were hospitalized with a first (21) or recurrent (27) episode of bronchial obstruction, and 10 controls were enrolled in this study. The serum concentration of sRAGE was assessed by ELISA methodology. A lung ultrasound was performed on all infants.

Results. We detected decreased sRAGE concentration in infants with a family history of asthma, severe obstruction with the necessity of oxygen supplementation, and lung ultrasound evidence for consolidation due to atelectasis and interstitial syndrome. There was a significant inverse age correlation ? sRAGE in serum decline with age ( p=0.005), and after 12 months of age, it remains the same. Recurrent wheezing in infants has been associated with the lowest sRAGE levels ? twice lower than the controls (578.73± 193.50 pg/mL vs. 1185.19±373.58pg/mL, p=0.001) and decreased compared to the first episode of wheezing (911.50 ± 371,47pg/mL, p=0.05).

Conclusions. Children with lower sRAGE are prone to more severe clinical presentation and the risk for recurrent wheezing due to a deficiency in its anti-inflammatory effect. This project was financially supported by GRANT 173/2022-Medical University of Sofia.