ESPE Abstracts

A female patient with atypical diabetes features, showing heterozygous mutations on G6PC2 (Glucose 6 phosphatase, catalytic subunit 2). Does explain all clinical manifestations or is it only polymorphism?

Introduction: Determing diabetes subtypes and classification is not clear for every patient and diagnosis can be difficult. Here in, we have found a quite interesting mutation on G6PC2 gene in a girl, 10 years old, showing atypical diabetes characteristics.

Case: A girl who was first diagnosed with obesity for 9 years and 7 months. In this time blood lipid levels and fasting glucose were in normal range. And she was admitted to endocrinology department due to asemptomatic hypergisemia at 11 years old. Keton was negative. There was no significant symptom except mild weight faiure. In her first physical examination; weight 54 kg (>99P) and height 146.7 cm (>99P) pubertal stage was Tanner 3. Random glucose was 363 mg/dl and insulin 3.76 ıu/ml c peptide was 1 ng/ml. HAb1c level was %10. Other biochemistry tests and hormonal profile were normal. Anti GAD level was 3 ıu/ml (<1). Firstly type 1 DM was diagnosed and insuline has been started but after 3 years her insulin requirment was still 0.4 u/kg/day and insulin resistance findings were noted. So genetic analyses was sent. A mutation was detected on G6PC2 gene. İt was known as glucose sensor (GCK) regulator and no mutation on this gene causing monogenic diabetes up to date.

Conclusion: It is known that this gene does not cause monogenic diabetes that is prone to type 2 diabetes and is generally active in fasting blood sugar regulation. So we treat patients as type 1 diabetes but some patients who can show the characteristics of all types of diabetes. With advanced genetic tests, diabetes classification can be made more clearly.