Vitamin D deficiency as a risk factor of acute constrictive laryngotracheitis in young children Berezhny VV, Mamenko MYe, Romanko MR, Romankevych IV, Glyadelova NP Shupyk National Medical Academy of Postgraduate Education, Kyiv, Ukraine PO.ID 1446 Results Abstracts Vitamin D deficiency as a risk factor of viral croup Respiratory tract infections (RTIs) are important causes of morbidity and mortality in young children. Acute constrictive laryngotracheitis (viral croup) is one of the most common syndromes in pediatric practice associated with viral respiratory infection. Croup remains the commonest reason for acute upper airway obstruction in children, but little is known about risk factors or its recurrence rate. Vitamin D is a regulator of calcium and phosphate homeostasis, and also has numerous extra-skeletal effects. These include effects on the cardiovascular system, central nervous system, endocrine system, and immune system, modulating the innate and adaptive system, influencing the production of endogenous antimicrobial peptides, and regulating the inflammatory cascade. The connection between vitamin D, calcium homeostasis, infections and immune function in the pediatric population indicates a possible role of vitamin D deficiency in viral croup occurrence. Variable Serum 25-OHD concentration <20ng/mL (n=26) 20-40ng/mL (n=26) 40-60ng/mL (n=18) >60ng/mL (n=10) n % Moderate croup 23 88,5 19 73,1 8 44,5* 2 20,0* Recurrent croup (>2 episode/yr) 30,8 Recurrent RTIs (>6 episode/yr ) 14 53,8 12 46,2 6 33,3 3 30,0 History of allergies 7 26,9 53,8* 18,0 1 10,0 *-the difference with children who had serum 25-OHD concentration, significant value, p<0,05 Serum 25(OH)D levels in young children at the age of 1-36 months with acute constrictive laryngotracheitis ranged from 5.43-114.3ng/ml (median 31.81ng/ml). Only 33.8% of patients had sufficient serum 25(OH)D levels (>40ng/ml). In 16.3% cases critically low levels of 25(OH)D (<15ng/ml) were detected. The median of serum 25(OH)D levels in children of the first year of life was 43.8 ng/ ml (QR: 35.0; 61.1) and in children aged 12-24 months it was 37.4ng/ml (QR: 26.0; 57.6; p=0.21). In patients aged 24-36 months the level of serum 25(OH)D was the lowest: 18.4ng/ml (QR: 13.3; 28.1, p<0.001) with the rate of vitamin D deficiency of 70.8%. Serum 25(OH)D levels <40 ng/mL were associated with an recurrent croup risk (χ²=6,5, p=0,011). Serum 25(OH)D levels <20 ng/mL were associated with moderate croup (88,5%, χ²=7,9, p=0,005). Objectives To evaluate the nutritional vitamin D status of young children with acute constrictive laryngotracheitis. Methods Conclusions Vitamin D deficiency can result in increased risks for recurrent episodes of viral croup. Hospital-based survey included 80 children aged 1-36 months with viral croup. Evaluation included clinical data, serum 25-hydroxyvitamin D (25(OH)D) level, serum calcium (mg/dl), phosphorous (mg/dl) and alkaline phosphatase (IU/L). The level of vitamin D above 40 ng/mL was considered as sufficient. 66.2% of young children with acute constrictive laryngotracheitis have low levels of serum 25(OH)D. References Shroff R, Knott C, Rees L. The virtues of vitamin D – but how much is too much? Pediatr Nephrol. 2010;25(9):1607–20. Misra M, Pacaud D, Petryk A, et al. Vitamin D deficiency in children and its management: review of current knowledge and recommendations. Pediatrics 2008; 122:398. Ginde AA, Mansbach JM & Camargo CA. Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey. Arch Intern Med 2009;169(4):384-390. Jolliffe DA, Griffiths CJ & Martineau AR. Vitamin D in the prevention of acute respiratory infection: systematic review of clinical studies. Journal of Steroid Biochemistry and Molecular Biology 2013;136:321-329. Bergman P, Lindh AU, Bjorkhem-Bergman L & Lindh JD. Vitamin D and respiratory tract infections: a systematic review and meta-analysis of randomized controlled trials. PLoS One 2013;8(6):1-9 Bergman P, Norlin AC, Hansen S, et al. Vitamin D3 supplementation in patients with frequent respiratory tract infections: a randomized and double-blind intervention study. BMJ Open 2012;2(e001663):1-10 Contacts: mariaromanko1986@icloud.com EAPS 2016 Geneva, Switzerland