diabetes mellitus
a metabolic disorder caused by ineffective production or utilization of the hormone insulin. Because of the insulin disruption, the patient is unable to oxidize and utilize carbohydrates in food. Glucose accumulates in the blood, causing weakness, fatigue, and the appearance of sugar in the urine. Fat metabolism is also disrupted so that end products of fat metabolism (ketones) accumulate in the blood. There are two major types of the disorder. Type 1 diabetes, formerly called insulin-dependent diabetes mellitus (IDDM), is characterized by a complete or near complete absence of endogenous insulin secretion, requiring patients to take daily insulin injections and to carefully manage the timing and size of their daily food intake to control their blood glucose levels; because this type usually occurs during childhood or early adolescence, it was formerly also called juvenile-onset diabetes (or juvenile diabetes). Type
2 diabetes, formerly called noninsulin-dependent diabetes mellitus (NIDDM), is characterized by reduced secretion of or resistance to insulin in the body and may be manageable through diet alone. In the past, it typically occurred in adulthood (and was formerly also called adult-onset diabetes); however, with the rise in childhood obesity, a significant risk factor for the disorder, Type 2 diabetes is increasingly seen in children as well as adults.