Purpose: MODY is a monogenic diabetes with autosomal dominant inheritance that usually occurs in adolescence or young adulthood. It constitutes 1% of diabetes cases in childhood. The diagnosis of MODY is very difficult due to genetic heterogeneity, rarity, and clinical overlap with other diabetes types. In recent years, the diagnosis of MODY has become easier with genetic developments. On the other hand, misinterpretation of results can cause confusion. In this study, it was aimed to retrospectively evaluate the clinical, laboratory and genetic data of our MODY patients.
Methods: Among the 583 diabetic patients followed up in our clinic,26 patients who met the diagnostic criteria of MODY were included in the study. The clinical and genetic characteristics of the cases were obtained retrospectively from the medical records.
Results: The mean age and duration of diabetes were 17.02±2.9 years and 6.8±2.7 years, respectively. Mean birth weight, body weight SDS and height SDS of the cases were 3.25 ± 0.39 kg, 0.04±1.4 and 0.1± 1.2, respectively. Two of the cases were obese (BMI>95 p), 2 of them were overweight (BMI 85-95 p), and 2 of them were underweight. The complaints at admission were coincidental high blood sugar (n=9), polyuria and polydipsia (n=6), incidental glucosuria (n=2), weight loss (n=1), diabetic ketosis (n=1), diabetic ketoacidosis (n=1). Diabetes history in at least 2 generations was present in 19 patients (14 with genetic diagnosis). Diabetes-associated autoantibodies were found to be negative in 24 of 26 cases. The mean C-peptide value and insulin value of the patients were 2.4±1.2ng/ml and 7.01±1.4mIU/ml, respectively. By next generation sequencing analysis, pathogenic (n=13) or possibly pathogenic (n=4) variants were detected in 17 (65%) of 26 cases. Variants were found in glucokinase (GCK) genes in 58.8% (n=10), hepatocyte nuclear factor 1A (HNF1A) in 29.4% (n=5), and in HNF4A and ABCC8 genes in 5.8% of 17 cases. Treatment consisted of diet alone in 15 (57%) patients, diet and oral antidiabetic (OAD) medication in 9 (34.2%) patients, diet and insulin and OAD treatment in 2.
Conclusion: In this study, GCK MODY was the most common MODY type. Recognition of MODY cases is essential for definite treatment and determination of prognosis. Studies in the field of molecular genetics facilitate the diagnosis of MODY, allow personalization of the treatment and the detection of other family members who may be ill. However, the detected variants should be interpreted together with the clinical follow-up of the cases.
15 Sep 2022 - 17 Sep 2022