Severe hypercalcaemia due to household cleaner ingestion

We report the case of a 59-year-old man with a history of type 2 diabetes, hypertension and chronic kidney disease who presented with symptomatic severe hypercalcaemia (calcium 15.8 mg/dL) and acute kidney injury. Evaluation revealed that the hypercalcaemia was not mediated by parathyroid hormone (PTH), PTH-related peptide or 1,25-hydroxyvitamin D. Adrenal insufficiency was subsequently diagnosed and was initially thought to be the aetiology of the hypercalcaemia. He was treated with intravenous fluid, pamidronate and started on hydrocortisone with resolution of his hypercalcaemia. Over the next several months, despite adherence to hydrocortisone therapy, the patient continued to have recurrent severe hypercalcaemia requiring hospitalisation. Additional laboratory evaluation showed similar results to the initial evaluation. On further questioning, the patient admitted to routinely ingesting the household cleaning product Comet, which contains a large amount of calcium. Psychiatric assessment confirmed the diagnosis of pica. The patient eventually discontinued ingestion of Comet with resolution of his hypercalcaemia.