Vitamin D toxicity resulting from overzealous correction of vitamin D deficiency

BackgroundVitamin D toxicity, often considered rare, can be life-threatening and associated with substantial morbidity, if not identified promptly. ObjectiveTo describe clinical and biochemical features, risk factors and management of patients with vitamin D toxicity seen between January 2011 and January 2013. MethodologyPatients presenting with vitamin D toxicity, between January 2011 and January 2013, at single tertiary care centre in Delhi-NCR, India, were included. Evaluation included detailed clinical history and biochemical tests including serum calcium, phosphorus, creatinine, intact parathyroid hormone and 25-hydroxyvitamin D (25(OH)D). ResultsSixteen patients with vitamin D toxicity could be identified. Clinical manifestations included nausea, vomiting, altered sensorium, constipation, pancreatitis, acute kidney injury and weight loss. Median (range) age was 645 (42-86) years. Median (range) serum 25(OH)D level and median (range) serum total serum calcium level were 371 (175-1161) ng/ml and 130 (111-157) mg/dl, respectively. Overdose of vitamin D caused by prescription of mega-doses of vitamin D was the cause of vitamin D toxicity in all cases. Median (range) cumulative vitamin D dose was 3600000 (2220000-6360000) IU. ConclusionOur data demonstrate an emergence of vitamin D toxicity as an increasingly common cause of symptomatic hypercalcaemia. Irrational use of vitamin D in mega-doses resulted in vitamin D toxicity in all cases. Awareness among healthcare providers regarding the toxic potential of high doses of vitamin D and cautious use of vitamin D supplements is the key to prevent this condition.