THE PHYSIOLOGICAL AND PHARMACOLOGICAL ROLE OF VITAMIN D IN IMMUNE MODULATION AND INFECTION OUTCOMES AMONG MALNOURISHED PEDIATRIC PATIENTS IN LOW-INCOME SETTINGS

To assess the ‘physiological and pharmacological role of Vitamin D in immune modulation and to determine its association with infection outcomes’ among malnourished pediatric patients. Methods: A cross-sectional study was conducted at the Department of Pediatrics, Hayatabad Medical Complex, Peshawar, from January 2023 to January 2024. A total of 73 malnourished children aged 6 months to 10 years were enrolled. Anthropometric indices, serum 25(OH)D, calcium, phosphate, alkaline phosphatase, hemoglobin, and C-reactive protein were measured. Infection outcomes including respiratory and diarrheal episodes, hospital stay, recurrent infections, and mortality were recorded. Statistical analysis was performed using SPSS version 26 with significance set at p < 0.05. Results: ‘Vitamin D deficiency was detected in 61.6% (n=45) of participants’. Deficient children had significantly lower weight-for-age Z-scores (−2.9 ± 0.8 vs. −2.3 ± 0.7, p = 0.02) and MUAC (11.5 ± 1.1 cm vs. 12.2 ± 1.0 cm, p = 0.03). Biochemically, deficiency was associated with lower calcium levels (8.2 ± 0.7 vs. 8.8 ± 0.6 mg/dL, p = 0.01), higher alkaline phosphatase (320 ± 85 vs. 270 ± 74 U/L, p = 0.03), and elevated CRP positivity (53% vs. 29%, p = 0.04). Clinically, acute respiratory infections (64% vs. 36%, p = 0.01), diarrheal illnesses (56% vs. 32%, p = 0.03), longer hospital stays (7.2 ± 2.1 vs. 5.9 ± 1.8 days, p = 0.04), and recurrent infections (47% vs. 25%, p = 0.02) were significantly more frequent among deficient children. Conclusion: Vitamin D deficiency was highly prevalent among malnourished children and significantly associated with increased infectious morbidity and prolonged hospitalization. Early detection and supplementation strategies may improve immune function and reduce infection burden in resource-limited pediatric populations.