Mitochondrial diabetes

Abstract

Diabetes mellitus comes in many shapes and forms. Apart from „type 1 and 2“, a plethora of more or less well delineated subtypes has been codified. Monogenetic forms are of particular significance because of high penetrance, early onset, associated comorbidities and implications regarding family screening. “Mitochondrial diabetes” results from defects of the respiratory chain and ensuing beta cell dysfunction. Its most important cause in adult age is the “MELAS-mutation” of mitochondrial DNA 3243A→G, with a reported prevalence ranging from 0.1% to 3%; hearing impairment is a frequent associated finding. Due to their protean ways of manifestation, mitochondrial disorders are notoriously difficult to diagnose. When non-obese individuals with compatible maternal family history develop diabetes, this entity should be considered and molecular testing performed.