Refractory hypercalcemia owing to vitamin A toxicity in a 4-year-old boy

Divisions of Paediatric Medicine (Lorenzo, Gill) and Endocrinology (Harrington), Department of Paediatrics, The Hospital for Sick Children and University of Toronto; Division of Clinical Pharmacology and Toxicology (Nadeau), Department of Medicine, University of Toronto, Toronto, Ont.

Divisions of Paediatric Medicine (Lorenzo, Gill) and Endocrinology (Harrington), Department of Paediatrics, The Hospital for Sick Children and University of Toronto; Division of Clinical Pharmacology and Toxicology (Nadeau), Department of Medicine, University of Toronto, Toronto, Ont.

Divisions of Paediatric Medicine (Lorenzo, Gill) and Endocrinology (Harrington), Department of Paediatrics, The Hospital for Sick Children and University of Toronto; Division of Clinical Pharmacology and Toxicology (Nadeau), Department of Medicine, University of Toronto, Toronto, Ont.

Divisions of Paediatric Medicine (Lorenzo, Gill) and Endocrinology (Harrington), Department of Paediatrics, The Hospital for Sick Children and University of Toronto; Division of Clinical Pharmacology and Toxicology (Nadeau), Department of Medicine, University of Toronto, Toronto, Ont.