Serum Vitamin D Level in Children With Bronchiolitis

Abstract Acute bronchiolitis is the most common lower respiratory tract infection during the first year of life. Vitamin D is an important contributing factor to the increasing incidence and severity of bronchiolitis over the past three decades. Numerous international studies have suggested that low vitamin D levels are associated with the severity of bronchiolitis. Purpose This study aimed to determine serum vitamin D levels in infants hospitalized with acute bronchiolitis in Myanmar. Method A cross-sectional analytical study was conducted in medical units of Yankin Children’s Hospital from August 2022 to July 2023. A total of seventy-five children aged one to twelve months old were included and the Wang clinical severity score was assessed for severity categorization. In this study, majority of children with severe bronchiolitis were found to be vitamin D deficient. Results A total of 75 children, 86% of the study population, were in the one-to-six-month- old age group and only ten children, 13.3 percent, were in the six-month to one -year-old age group. According to the Wang clinical severity score, severe bronchiolitis was found in 64% of the study population, and non-severe bronchiolitis was detected in 36%. In this study, the mean vitamin D level in the studied population was 38.54 ± 17.67 nmol/L in non-severe bronchiolitis patients and 35.31 ± 15.83 nmol/ L in severe bronchiolitis patients. In the present study, 94.1% of severe bronchiolitis cases were vitamin D deficient, and only 5.9% of none severe bronchiolitis cases were vitamin D deficient. A total of 59.3% of severe bronchiolitis cases were vitamin D insufficient, and 40.7% of non-severe bronchiolitis cases were vitamin D insufficient. Conclusion All of the vitamin D sufficient patients had non- severe bronchiolitis. Therefore, there was a statistically significant association between vitamin D levels and the severity of bronchiolitis.