Mellitus

Also Known As:  Diabetes mellitus, Blood Sugar, Blood Glucose, Glucose

Related Diaseases: Kidney Diseases, Pancreatic Diseases, Heart Disease, Heart Attack, Stroke, Metabolic Syndrome, Acidosis and Alkalosis, Neuropathy, Pregnancy

Definition of diabetes mellitus:

• Diabetes mellitus is a group of metabolic disorders of carbohydrates metabolism in which glucose is not properly utilized, leading to hyperglycemia.
• Criteria for the diagnosis of diabetes Mellitus:
  • Polyuria, polydipsia and rapid weight loss.
  • Insulinopenia decreased insulin due to the loss of β-cells of the pancreas.
  • Most patients have autoantibody were called an autoimmune process.
  • While no cause known is called idiopathic type.

Type of Diabetes  Mellitus:

1. Type 1 diabetes mellitus is insulin-dependent/ juvenile-onset and its types are:
   • Autoimmune type.
   • Idiopathic type.
2. Type 2 diabetes mellitus is non-insulin dependent or adult on set type.
   • Patients have minimal symptoms.
   • This is not dependent on insulin to prevent ketonuria.
   • The insulin level may be normal or decreased or increased.
   • Most patients have impaired insulin action.
3. Gestational diabetes mellitus.
   • This is first diagnosed during pregnancy.
   • Already known cases of diabetic women are not included in this group.
   • This occurs in 6 to 8% of the pregnant ladies.
   • These ladies are at increased risk later on to develop diabetes mellitus (6 to 62% of these ladies).
4. Impaired glucose tolerance (IGT).
   • This group has less fasting glucose than required for diabetes mellitus.
   • An oral glucose tolerance test is needed to diagnose this group.
   • The overt case develops 1 to 5% per year.
   • Microvascular diseases are very uncommon in this group.
5. Impaired fasting glucose (IFG).
   • This is diagnosed by fasting glucose values between normal and diabetics individuals.
   • This is a metabolic stage between normal glucose and diabetes mellitus.
   • There is an increased risk for the development of diabetes and cardiovascular disease.

Latest classification criteria for diabetes mellitus

1. Diabetes mellitus:
   1. Presence of classical symptoms.
   2. If fasting glucose level 126 mg/dl (>7.0 mmol/L) or above should be labeled as D. Mellitus (when this value is found two times).
   3. One random glucose level of more >200 mg/dl  (11.1 mmol/L) with symptoms of polyuria, polydipsia, and polyphagia are considered diagnostic of diabetes.
   4. HbA1c more than 6.5 % diagnostic for Diabetes.
   5. The 2-hour postprandial glucose level of  ≥200 mg/dl  (11.1 mmol/L) during OGTT.
2. Impaired fasting glucose = > 126 mg/dl. (fasting glucose level 110 to 125 mg/dL (6.1 to 7.0 mmol/L).
3. Impaired glucose tolerance when:
   1. Fasting glucose < 126 mg/dl (7 mmol/L).
   2. OGTT 2 hours sample is 140 mg to 199 mg/dl (7.8 to 11.1 mmol/L).

Criteria for the diagnosis of diabetes mellitus

• Fasting blood glucose level:
  • 126 mg/dL (7.0 mmol/L) or higher is considered diagnostic.
• Random/ non fasting blood glucose level:
  • 200 mg/dL (11.1 mmol/L) is diagnostic.
• Oral glucose tolerance test with 75 G of glucose:
  • 2-hour sample 200 mg/dL  (11.1 mmol/L) or higher value is diagnostic.

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