Individuals with mitochondrialRelated to the mitochondria. disorders are at increased risk of developing both high blood sugars (diabetes mellitusA variable disorder of carbohydrate metabolism and usually characterized by the inadequate secretion or utilization of insulin by excessive urine production, excessive amounts of sugar in the blood an) and low blood sugars (hypoglycemiaLow blood sugar.). We will review considerations for diagnosis and management of these conditions, and touch on related endocrine problems, including growth problems and adrenal insufficiency. Our goal is for individuals and families to be well informed for future discussions of these endocrine issues with their clinical care teams.