Broncho-obstructive syndrome (BOS) is one of the most common clinical conditions in pediatric practice, characterized by airflow limitation due to inflammation, bronchial hyperreactivity, and increased mucus production. This syndrome frequently accompanies acute respiratory infections, bronchial asthma, and recurrent wheezing disorders in children. In recent years, increasing scientific interest has been directed toward the role of vitamin D in immune regulation and respiratory health, particularly in pediatric populations.

Vitamin D is known to exert immunomodulatory, anti-inflammatory, and antimicrobial effects, which may influence the course and severity of broncho-obstructive conditions. Deficiency of vitamin D has been widely reported among children and has been associated with increased susceptibility to respiratory infections, frequent exacerbations of bronchial obstruction, and poorer clinical outcomes. However, the therapeutic and preventive potential of vitamin D supplementation in children with broncho-obstructive syndrome remains an area of active research.

The purpose of this study is to assess the effectiveness of vitamin D supplementation in children diagnosed with broncho-obstructive syndrome by evaluating its impact on the frequency and severity of obstructive episodes, clinical symptoms, and overall disease progression. The findings of this research may contribute to improving treatment strategies, reducing the recurrence of bronchial obstruction, and enhancing the quality of life in pediatric patients. Understanding the role of vitamin D in the management of broncho-obstructive syndrome could support the development of evidence-based recommendations for pediatric respiratory care.

Broncho-obstructive syndrome, vitamin D, pediatric respiratory diseases

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