Endocrine Abstracts

Introduction

Diabetic ketoacidosis (DKA) is associated with Type 1 diabetes mellitus (T1DM), whilst hyperglycemic hyperosmolar state (HHS) with Type 2 (T2DM). HHS has been well described as a presentation of T1DM in children, but not in adults. We present present a case of T1DM presenting in a young adult as HHS, with severe hyperglycemia but without acidosis.

Case report

A 21 year old male presented with a 4 5 day history of weakness, thirst, polydipsia and polyuria. He had vomited once. He was previously well but had received Growth Hormone for idiopathic short stature between the ages 15 18. He has a cousin with T1DM. On examination he was afebrile, pulse 62, BP 125/57, BMI 22. Blood glucose was 993 mg/dl, Na⁺ 131 mM, K⁺ 5.2 mM, creatinine 1.2 mg/dl, pH 7.353, bicarbonate 23.5 mM, serum osmolality 319 mOsm/kg. Anion gap not measured. Urine ketones 15. HbA1c 10.2%. In view of his age he was treated as for DKA with intravenous fluids and insulin. He displayed substantial insulin resistance and at discharge required a total of 82U daily, about 1.4 U/kg/day, . Subsequently his insulin requirement fell and was 24U daily two months after discharge. Serological studies showed positive anti-GAD and anti-islet cell antibodies at over 2000 [ < 5] and over 900 [ < 30] respectively. He is now well controlled on treatment with an insulin pump and continuous monitoring system, most recent HbA1c 6.6%. However, his younger sister age 9 has recently been diagnosed with celiac disease. Previous serological testing of our patient for celiac disease was negative but we are now repeating this as well as checking diabetes antibodies in the sister.

Discussion

This patient presented with a picture typical for HHS in T2DM, with severe hyperglycemia but without metabolic acidosis. Urine ketone testing showed minimal ketones, as a result of this case we have introduced blood ketone (betahydroxybutyrate) into the hospital. In spite of his normal weight he exhibited severe insulin resistance presumably as a result of glucotoxicity, but with sufficient residual insulin secretion to prevent ketoacidosis. Whether there is an association with his previous GH treatment is unclear. The recent diagnosis of celiac disease in his sister strengthens the implication of immunogenetic factors.