Rare presentation of vitamin D toxicity with hypertriglyceridemia and pancreatitis.

Summary: Vitamin D is commonly recommended for daily intake as dietary sources are often insufficient. However, prolonged high-dose use can lead to serious complications. We present a rare case of a 2-month-old infant who developed severe hypercalcemia and hypertriglyceridemia due to an accidental overdose of 25-OH vitamin D, leading to hypertriglyceridemia and pancreatitis. The management challenges encountered while managing this case were the need for high glucose infusion rate fluids with insulin for hypertriglyceridemia, electrolyte imbalances secondary to forced diuresis, difficulties in providing fat-free formula, gradual introduction of maternal breastfeeding due to pancreatitis and rebound hypercalcemia requiring steroid treatment. These complications, rarely reported in hypervitaminosis D, highlight the need for careful vitamin D dosing in the pediatric population. Potential areas leading to vitamin D intoxication include improper formulation, lack of clarity in prescribing, concurrent use of other vitamin D-containing supplements, parental access to the internet for health supplements and easy availability. Learning points: Children presenting with polyuria and failure to thrive should be screened for hypercalcemia as one of the causes. Hypertriglyceridemia with pancreatitis can be managed with IV insulin infusion, high dextrose-containing fluids and gradual feed establishment as pancreatitis improves. The case report underscores the serious and potentially life-threatening complications associated with vitamin D intoxication while emphasizing the importance of educating parents on safe dosage practices.