Insulin resistance syndrome presenting with diabetic ketoacidosis — a rare presentation

We report an adolescent male who presented with diabetic ketoacidosis (DKA). He was diagnosed to have type 1 diabetes mellitus at the age of 12 years and had been initiated on insulin. On physical examination, he had a distinct senile-looking coarse facies with clinical stigmata of insulin resistance in the form of acanthosis nigricans and hypertrichosis. Additionally, he required more than 3 units/kg/day of insulin during recovery from DKA. The clinical and biochemical profile of the patient led to the suspicion of insulin resistance syndrome which was confirmed by the detection of homozygous missense variation in exon 2 of the insulin receptor gene (INSR) on clinical exome testing. The patient was put on insulin sensitizers along with insulin which led to a marked improvement in glycemic control. The case highlights the importance of a good clinical examination for a correct diagnosis and discusses the challenges in management.