ODP255 Woman With Maturity-Onset Diabetes of the Young Type 2 (MODY2) Mistakenly Diagnosed and Treated as Type 2 Diabetes Mellitus

BACKGROUND: MODY2 is a rare, monogenic form of diabetes, caused by mutations in the glucokinase gene (GCK), and is often misclassified as type 2 diabetes. Clinical case: A 37-year-old woman, during childhood, at the age of 9, was characterized as overweight and had a poor diet, despite being physically active. Her pediatrician diagnosed her with DM2 and started treatment with metformin. However, there was no improvement in fasting glucose levels, so the family decided to stop the medication on their own. In 2008, the patient became pregnant, presenting fasting glucose levels between 120-130 mg/dl (n<99 mg/dl), and continued without hypoglycemic treatment. In 2010, she resumed treatment for glycemic control having used: metformin, sulphonylurea, IDDP4, and basal insulin. Despite the various treatments tested, there was altered fasting glycemia, in the 130mg/dl range. In 2012, she increased her physical activity by training for a half marathon run. At the peak of her form, but maintaining hyperglycemia (always measuring while fasting), she started liraglutide 1.8mg. In 2019, she presented episodes of malaise during training, being indicated by her physician, to discontinue liraglutide, then starting dapagliflozin, but there was still no improvement of blood glucose levels. In August 2019, she was instructed to take the following medications: insulin degludec, liraglutide, and dapagliflozin. Current weight was 53kg, height 1,57cm and a BMI 21,5kg/. Laboratory exams were requested with the following results: A1C 6,6% (n: <5,7%), mean glycemia 143mg/dL (n: 70-99 mg/dL), fasting glycemia 127mg/dL (n: <100mg/dL), urea 24mg/dL (n: 13-43 mg/dL), creatinine 0,83mg/dL (n: 0,8-1,3 mg/dL), AST 16U/L (n: 10-34 U/L), ALT 17U/L (n 10-130 U/L), LDL 109mg/dL (n<100mg/dl), HDL 80mg/dL (n>60 mg/dL), TG 90mg/dL (n<150 mg/dL), total cholesterol 207mg/dL (<200 mg/dL). Faced with the suspicion of diabetes with different behavior than DM1 and DM2, genetic testing was requested for confirmation. In September 2019, the result arrived, pointing out a genetic change in heterozygosis in the GCK gene. This is a rare mutation that results in the depletion of the phenylalanine amino acid at position 150 of the protein glucokinase. This result confirmed the diagnose of MODY type 2. The patient was oriented to discontinue anti-hyperglycemic agents, maintain a low glycemic index diet, and daily physical exercises. Thus, she has been maintaining excellent glycemic control and adequate weight. CONCLUSION: Suspicion and characterization of MODY through clinical history, and confirmation of diagnosis through genetic testing, is essential to avoid unnecessary or inefficient treatments, and to ensure a better quality of life for the patient. Presentation: No date and time listed