STUDYING VITAMIN D INTOXICATION IN CHILDREN

Ingesting high amounts of vitamin D results in soft tissue calcification, nephrocalciosis, neurologic complications and even death in severe cases. The aim of this study was to evaluate vitamin D intoxication in children who referred to children's Hospital of Tabriz/Iran. The medical documents of all children admitted in Children's Hospital of Tabriz with diagnosis of Vitamin D intoxication from 2000 to 2012 were studied, retrospectively. The variables were demographic characteristics, clinical and laboratory findings and outcome of patients. During 12 years, 20 patients (14 boys, 6 girls) with diagnosis of hypervitaminosis D with a mean age of 17.2±6.4 months (9-28 months) were evaluated. The most common symptoms were: anorexia (85%), vomiting (80%), weight loss (70%), dehydration (55%), constipation (45%) and polydipsia (40%). The mean serum level of total calcium was 13.5±3.7 mg/dl (12-17 mg/dl). The mean level of phosphor, 25(OH) D and parathormone were 6.3±1.4 mg/dl, 191.7±87.6 ng/ml and 14±8.8 ng/ml respectively. Ten patients (50%) had medullary nephrocalcinosis in renal sonography. Treatment modalities were: hydration with normal saline in all patients, frusemide in 16(80%), prednisolon in 15 (75%) and pamidronate in 3 (15%) patients. All patients were followed for 1-5.5 years. In the follow-up period recurrence of clinical symptoms and hypercalcemia was not seen in any patient. However nephrocalcinosis was persistent in the last follow up visit in all ten cases. Administration of high doses of vitamin D without considering its serum level and without considering the criteria of rickets may result in vitamin D intoxication. Late diagnosis of intoxication causes acute and long term complications.