Diabetes Mellitus (Type I and Type II)
Definition : A group disorders that have a variety of genetic causes, but have glucose intolerance as a common thread.
Characteristic
A. Classifications.
1. Type I-insulin dependent diabetes mellitus (IDDM) 2. Type II-noninsulin dependent diabetes mellitus (NIDDM).
3. Gestational (GDM)-increased blood glucose levels during pregnancy.
4. Impaired glucose tolerance (IGT). Plasma glucose levels vacillate between normal or increased (formerly latent, borderline, and subclinical diabetes).
B. Etiology.
1. Genetic factors.
a. Presence of HLA antigens.
b. Individual genes located on "shortarm" of sixth chromosome.
2. Viruses.
a. Type I diabetes occurs at time viral diseases are prevalent-autumm and spring.
b. Type I onset often preceded by viral attack.
c. Coxsackie B4 is found in pancreas.
d. Twenty viruses associated with diabetes.
C. Pathophysiology.
1. Type I-defect in insulin secretion in dying beta collo.
2. Type II-defect can occur in any of the following:
a. Defect in preceptor abnormality (circulation).
b. Defect receptor abnormality (cell membrane).
c. Defect postreceptor (target cell).
3. Autoimmune response.
a. Presence of islet-cell antibodies.
b. Tyroid deficiency.
4. Inability to utilize glucose.
a. Normal or above levels of insulin, but not utilized.
b. Circulating insulin unable to trigger changes in cell membrane. |
