55 Pathophysiology of DM (Henry)

Question 1

. Identify the distinguishing features between Type I and Type II diabetes mellitus as they relate to: b-cell function, insulin sensitivity, blood glucose levels, Hb1Ac measurements, and ketone production.

Answer 1

Type I: B cell destruction by infiltration of activated T-lymphocytes, absolute insulin deficiency, Progression is very dif from type II, takes some time before sx are experienced. High blood glucose. Can lead to ketone production.
Type II: Insulin resistance and insulin secretory defect. Increase in B cell mass. Normal blood glucose levels.

Question 2

Describe the relative significance of obesity, genetics, environment, and the immune system in the development of Type I and Type II diabetes.

Answer 2

Type I: Genetic predisposition (key genes related to MHC locus). Immune mediated. Environmental factors (viruses/toxins that have molecular mimicry to B cells?)
Type II: Genetic predisposition (if twin has type II, 90% chance you’ll get it, Type I is 25-50%), obesity (huge correlation btwn visceral adiposity and resistance to insulin), and environmental factors

Question 3

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List the signs and symptoms, as well as the cause of the signs and symptoms, of Type I and Type II diabetes.

Answer 3

Type I: Can detect autoantibodies many years before onset of disease. Polyuria, thirst, blurred vision, wt loss, weakness, dizzy, sensory nerve dysfunction (paresthiasis), level of consciousness
Type II: High insulin and normal plasma glucose. Metabolic syndrome (see below). Asympto initially. Infections (from elevated glucose), neuropathy (retinal, peripheral), polyuria, thirst, etc, obesity and metabolic syndrome.

Question 4

Compare and contrast the metabolic changes that occur in patients with Type I or Type II diabetes.

Answer 4

Type I: Increase in gluconeogenesis, increase in glycogenolysis, decreased glycolysis, promote ketogenesis.
Type II: Metabolic syndrome (hyperinsulinemia, dyslipidemia, hypertension) – can result in coronary artery disease and stroke. Insulin increases Na retention, thus high BP.

Question 5

Predict common therapeutic strategies employed and the rationale for these strategies in treating Type I and Type II diabetes mellitus.

Answer 5

Type I: Diet, patient education, and INSULIN.
Type II: Diet, pt. education, lots of pharmacological strategies (increase insulin secretion/action by mimicking GLP1, inhibit degradation of GLP1. Inhibit K secretion, etc. etc.) Insulin can be used when other strategies don’t work well.

Question 6

Recognize the acute complications potentially experienced by patients with diabetes mellitus and the general therapeutic approach to addressing these complications.

Answer 6

Hypoglycemia – sx from ANS (tachycardia, sweating, tremors, nausea, hunger), Neurologic sx (confusion, irritable, blurred vision, tired)
Treat w/ glucose or glucagon.

Diabetic Ketoacidosis – insulin deficiency causes mobilization of energy stores which includes ketogenesis and thus metabolic acidosis. More common in Type I. Treat by restoring plasma vol., reduce glucose, correct acidosis, replenish

Question 7

Be familiar with common measurements used to monitor glycemic control.

Answer 7

Cap blood testing, urine ketone testing, cap ketone testing, glycated hemoglobin testing.