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Diabetes mellitus

/məˈlītəs/  /ˈmeli-/


1. A group of metabolic diseases in which a person has high blood sugar, either because the pancreas does not produce enough insulin, or because cells do not respond to the insulin that is produced. This high blood sugar produces the classical symptoms of polyuria (frequent urination), polydipsia (increased thirst) and polyphagia (increased hunger).

There are three main types of diabetes mellitus (DM).

  • Type 1 DM results from the body’s failure to produce insulin, and currently requires the person to inject insulin or wear an insulin pump. This form was previously referred to as “insulin-dependent diabetes mellitus” (IDDM) or “juvenile diabetes”.
  • Type 2 DM results from insulin resistance, a condition in which cells fail to use insulin properly, sometimes combined with an absolute insulin deficiency. This form was previously referred to as non insulin-dependent diabetes mellitus (NIDDM) or “adult-onset diabetes”.
  • The third main form, gestational diabetes occurs when pregnant women without a previous diagnosis of diabetes develop a high blood glucose level. It may precede development of type 2 DM.

Other forms of diabetes mellitus include congenital diabetes, which is due to genetic defects of insulin secretion, cystic fibrosis-related diabetes, steroid diabetes induced by high doses of glucocorticoids, and several forms of monogenic diabetes.


2. Diabetes caused by a relative or absolute deficiency of insulin and characterized by polyuria. (

3. Relative or absolute lack of insulin leading to uncontrolled carbohydrate metabolism. In juvenile onset diabetes (that may be an autoimmune response to pancreatic _ cells) the insulin deficiency tends to be almost total, whereas in adult onset diabetes there seems to be no immunological component but an association with obesity. (

4. The commonest form of diabetes, caused by a deficiency of the pancreatic hormone insulin, which results in a failure to metabolize sugars and starch. Sugars accumulate in the blood and urine, and the byproducts of alternative fat metabolism disturb the acid–base balance of the blood, causing a risk of convulsions and coma. (Google Dictionary)

5. A condition characterized by hyperglycemia resulting from the body’s inability to use blood glucose for energy. In type 1 diabetes, the pancreas no longer makes insulin and therefore blood glucose cannot enter the cells to be used for energy. In type 2 diabetes, either the pancreas does not make enough insulin or the body is unable to use insulin correctly. (

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