From the Guidelines
Vitamin D toxicity in pediatrics is a rare condition that typically presents with symptoms related to hypercalcemia, and the threshold for acute toxicity has not been well-established, but serum concentrations >375 nmol/L are associated with acute hypercalcaemia and hyperphosphataemia. The symptoms of vitamin D toxicity in children can vary, but they often include nonspecific symptoms such as irritability, vomiting, poor feeding, constipation, abdominal pain, and fatigue, as well as more severe manifestations like polyuria, polydipsia, dehydration, and in extreme cases, renal calculi, nephrocalcinosis, and cardiac arrhythmias 1.
Key Findings
- The main function of vitamin D is the regulation of calcium and phosphate, and it is essential for bone health 1.
- The ESPGHAN Committee on Nutrition recommends a total daily vitamin D intake of 400 IU/day for infants and 600 IU/day for children and adolescents 1.
- Prolonged daily intake up to 10,000 IU or up to serum concentrations of 25(OH)D of 240 nmol/L appears to be safe, but serum concentrations >375 nmol/L are associated with acute hypercalcaemia and hyperphosphataemia 1.
- Tolerable upper intake levels identified by the IOM are 1000 IU/day for infants ages 0-6 months, 1500 IU/day for infants ages 7-12 months, 2500 IU/day for children ages 1-3 years, 3000 IU/day for children ages 4-8 years, and 4000 IU/day for children and adolescents ages 9-18 years (and adults) 1.
Prevention and Treatment
- Prevention involves appropriate dosing of supplements and regular monitoring of vitamin D levels in children receiving high-dose therapy.
- Treatment involves immediate discontinuation of vitamin D supplements, low calcium diet, adequate hydration, and in severe cases, administration of corticosteroids, calcitonin, or bisphosphonates under specialist guidance.
- Loop diuretics like furosemide (0.5-1 mg/kg/dose) may be used to enhance calcium excretion. The key to managing vitamin D toxicity is early recognition and prompt treatment to prevent long-term complications, and the recommended treatment approach is based on the severity of the toxicity and the presence of any underlying medical conditions.
From the Research
Vitamin D Toxicity Presentation in Pediatrics
- Vitamin D toxicity is not a common case in pediatrics, but it can occur due to a lack of public education about the permissible limits of vitamin D intake 2.
- Vitamin D toxicity (VDT) refers to serum 25(OH)D levels that exceed 100 ng/mL (250 nmol/L) or is defined as hypervitaminosis D 2.
- Hypercalcemia is a common condition of vitamin D toxicity, which can be induced by vitamin D and its metabolites in moderate levels 2.
Clinical Presentation
- Clinical presentation of vitamin D toxicity in pediatrics can include severe hypercalcemia, hypercalciuria, or nephrocalcinosis 3.
- Mild hypercalcemia and hypervitaminosis can also occur in infants with rickets using currently recommended doses of vitamin D 3.
- Hypercalcemia can be asymptomatic in children and adolescents, but rare cases of vitamin D intoxication can present with dramatic life-threatening symptoms 3.
Treatment and Management
- Treatment of vitamin D toxicity in pediatrics can include discontinuing vitamin D intake, using activated charcoal, furosemide, prednisone, and calcitonin, and rehydration using intravenous sodium chloride 0.9% and dextrose fluid therapy 2.
- Prednisolone is less effective in the treatment of children with severe hypercalcaemia secondary to vitamin D intoxication, and timely implementation of other treatment regimens should be considered 4.
- Glucocorticoids and bisphosphonates can be used to treat long-term hypervitaminosis D-induced hypercalcaemia 5.
- Glucocorticoid effects in vitamin D intoxication can include a dramatic reduction in both mean serum calcium levels and mean 24-hour urinary calcium excretion 6.