Iatrogenic hypercalcaemia in an elderly lady

An 83-year-old lady known to have type 2 diabetes mellitus, hypertension and primary hypothyroidism presented with the complaints of increased thirst of one month duration, diffuse abdominal pain, constipation and mild nausea of one week duration. She was found to have hypercalcaemia. Review of her treatment records revealed that she had received a high dose ofvitamin D (average dose of 63,000 IU/day) over two months. Serum vitamin D was 347 ng/mL. Patient was advised to withhold all calcium and vitamin D preparations and further managed with intravenous 0.9% saline, diuretics and zoledronic acid. She improved clinically; her serum calcium levels became normal and she was subsequently discharged in stable condition. This case illustrates that inappropriate therapy with grossly excessive doses of vitamin D can result in intoxication leading on to hypercalcaemia.