Maturity-onset diabetes of the young: difficult differential diagnosis

Maturity-onset diabetes of the young (MODY) is a monogenic variant of diabetes characterized by the primary dysfunctions of pancreatic β-cells. MODY accounts for 1–2% of all variants of diabetes. MODY is generally associated with HNF1A gene mutation. The hallmarks of MODY are an autosomal dominant inheritance pattern, the onset of the disease in the young age, stable C-peptide level over a long period, the lack of the autoantibodies considered as the markers of diabetes, and the lack of ketoacidosis at disease onset. Considering that MODY manifests in children and young individuals, these patients are commonly diagnosed with type 1 diabetes. However, due to the atypical clinical signs of type 1 diabetes and the similarity of this disease to type 2 diabetes, these patients are often misdiagnosed with type 2 diabetes. This case report illustrates the differential diagnosis of diabetes in a patient with unusual disease course. The attention is focused on the features of MODY course. The indications to molecular genetic testing to verify the diagnosis are addressed.KEYWORDS: diabetes, maturity-onset diabetes of the young, monogenic diabetes, sulfonylureas, molecular genetic testing, LADA, pancreatogenic diabetes.FOR CITATION: Lobanova K.G., Titova V.V., Dolgova K.S. Maturity-onset diabetes of the young: difficult differential diagnosis. Russian Medical Inquiry. 2020;4(6):372–376. DOI: 10.32364/2587-6821-2020-4-6-372-376.