Diabetes Flashcards
Which hormone do alpha cells release?
Glucagon.
Which hormones do beta cells release?
Insulin and amylin.
Which hormone do delta cells release?
Somatostatin.
Which hormone do PP cells release?
Pancreatic polypeptide.
What is the action of glucagon?
Causes cells to release stored food into the blood.
What is the function of insulin?
Allows cells to take up glucose from the blood.
What are the functions of amylin?
Slows glucose absorption in small intestine and suppresses glucagon secretion.
What are the functions of somatostatin?
Decreases gastro-intestinal activity, suppresses glucagon and insulin secretion.
Diabetes mellitus can occur due to…
Absolute insulin deficiency. Impaired release of insulin from pancreatic beta cells. Inadequate/defective insulin receptors. Production of inactive insulin or insulin that is destroyed.
What characterizes diabetes mellitus type 1A?
Absolute insulin deficiency.
What causes insulin deficiency in diabetes mellitus type 1A?
Autoimmune destruction of beta cells. (Islet cell antibodies and insulin antibodies).
What are the causes of diabetes mellitus type 1A?
Genetic predisposition. Environmental triggers. T-lymphocytes-mediated hypersensitivity reaction against beta cell antigens.
What is the difference between diabetes mellitus type 1A and type 1B?
Type 1B is idiopathic, and involves variable insulin dependency.
Who is at risk for diabetes mellitus type 1B?
Africans, Asians, and those who have a family history of diabetes mellitus type 1B. (It is strongly inherited).
What are the causes of diabetes mellitus type 2?
Insulin resistance, increased liver production of glucose, beta cell dysfunction.
What are the risk factors for diabetes mellitus type 2?
Genetic. Environmental. Obesity (esp. upper body obesity). Physical inactivity.
What does insulin resistance mean?
Failure of target tissue to respond to insulin.
What is the result of insulin resistance?
Decreased glucose uptake by skeletal muscle.
What are the causes of beta cell dysfunction?
Decreased mass (genetic/prenatal). Increased apoptosis/decreased regeneration. Exhaustion (d/t chronic insulin resistance). Desensitization (d/t chronic glucotoxicity). Destruction (i.e. lipotoxicity). Toxins/deposits (i.e. amyloid).
What is gestational diabetes mellitus?
Glucose intolerance developing during pregnancy.
What are the risk factors for gestational diabetes mellitus?
Glycosuria. Strong family history of DM type 2. Severe obesity. Polycystic ovary disease. Prior history of gestational diabetes mellitus. Previous delivery of large-for-gestational-age infant.
What are some fetal complications of gestational diabetes?
Macrosomia. Hypoglycemia (>9 lbs 4 oz). Hypocalcemia (decreased parathyroid gland function). Polycythemia. Hyperbilirubinemia.
What are the manifestations of diabetes mellitus type 1?
Rapid onset. Weight loss due to fluid loss and use of fat stores.
What are the manifestations of diabetes mellitus type 2?
Insidious. Weight gain.
What are the manifestations that are common to both type 1 and type 2 diabetes?
Polyuria. Polydipsia. Polyphagia (usually type 1). Blurred vision. Weakness/fatigue. Paresthesia. Infection.
Why does diabetes mellitus cause polyuria?
Glomeruli in kidneys unable to reabsorb glucose; spills into urine. Glucose is an osmotically active molecule, so it pulls water with it.
Why does diabetes mellitus cause polydipsia?
Loss of water results in intracellular dehydration; brain recognizes this and signals thirst.
Why does diabetes mellitus cause polyphagia?
Because carbohydrate, fat, and protein stores are used.
Why does diabetes mellitus cause blurred vision?
Hyperosmolar fluid affects lens and retina.
Why does diabetes mellitus case weakness/fatigue?
Decreased fluid in cardiovascular system.
Why does diabetes mellitus cause paresthesia?
Peripheral sensory nerve dysfunction.
Why does diabetes mellitus cause infection?
Organisms are attracted to high glucose levels.
What is the normal level of fasting blood glucose?
> 5.7 mMol/L
What is an oral glucose tolerance test?
Measures ability to store glucose. 75 grams of concentrated glucose solution given at intervals. Normal response is a return to normal blood glucose level within 2-3 hours.
What is a normal blood glucose level 2 hours after glucose tolerance test?
<7.8 mMol/L
What is glycosylated hemoglobin?
Hemoglobin becomes glycosylated to form HbA1 (A1c). Identifies average plasma glucose concentration over long period. (6-12 weeks)
What is the normal range for glycosylated hemoglobin?
3.9-5.6%
What is diabetic ketoacidosis?
Ketones are produced when the liver converts glucose for use and mobilizes fatty acids for energy.
What abnormal blood findings indicate diabetic ketoacidosis?
Low bicarbonate. Low pH. Urine and serum ketones. Metabolic acidosis.
What are the gastrointestinal manifestations of diabetic ketoacidosis?
Nausea, vomiting, abdominal pain/tenderness, fruity breath.
What are the cardiovascular system manifestations of diabetic ketoacidosis?
Dehydration.
Hypotension/tachycardia (not enough vascular volume).
What are the respiratory manifestations of diabetic ketoacidosis?
Kussmaul breathing (rapid, deep breathing, fairly regular; body is trying to breathe off CO2)
What are the central nervous system manifestations of diabetic ketoacidosis?
Confusion, stupor, coma.
What are the treatment goals for diabetic ketoacidosis?
Improve circulatory volume and tissue perfusion. Decrease blood glucose. Correct acidosis. Correct electrolyte imbalance.
How to improve circulatory volume and tissue perfusion in diabetic ketoacidosis…
IV fluids.
How to decrease blood glucose in diabetic ketoacidosis…
Low-dose insulin therapy.
What is the danger of giving too much insulin during diabetic ketoacidosis?
Will lower serum osmolality and cause cerebral edema.
What is a hyperosmolar hyperglycemic state?
Hyperglycemia >33 mMol/L. Hyperosmolarity of plasma. No ketoacidosis (there is some insulin available). CNS depression.
What are risk factors for hyperolsmolar hyperglycemic state?
Type 2 diabetes mellitus. Acute pancreatitis. Severe infection. Myocardial infarction. Total parenteral nutrition.
What are the central nervous system manifestations of hyperosmolar hypergylcemic state?
Insidious, can mimic a stroke. Weakness. Hemiparesis. Aphasia. Muscle fasciculations. Hyperthermia. Hemianopia. Nystagmus. Visual hallucinations. Seizures. Coma.
How to treat hyperosmolar hyperglycemic state…
Careful monitoring. Replace fluid loss gradually (prevent cerebral edema). Potassium lost during diuresis needs to be replaced carefully. Poor prognosis.
What causes hypoglycemia?
Insulin or oral hypoglycemic. Alcohol decreases liver gluconeogenesis. Exercise. Dieting. Endocrine disorders.
What are the manifestations of hypoglycemia?
Rapid onset, variable. Headache. Difficulty problem solving. Confusion. Behavioural changes. Coma. Seizure. Hunger. Anxiety. Tachycardia. Sweating. Constriction of skin vessels.
What is the treatment of hypoclycemia?
Rapid delivery of oral glucose (15g). Glucose IV (D50W) if emergency. Glucagon IM or s/c if unable to take oral glucose.
What is the Somogyi Effect?
Rebound high blood sugar in response to a low blood sugar. Can be in cyclic episodes.
What are neuropathies?
Blood supply altered due to thickening of vessel walls over time. Demyelination of Schwann cells slows nerve conduction.
What is diabetic nephropathy?
Kidney damage due to high blood glucose. Leading cause of kidney disease.
What are the risk factors for diabetic nephropathy?
Genetic and familial (Natives, Hispanic, African descent). Hypertension. Poor blood glucose control. Hyperlipidemia. Smoking.
What causes retinopathies?
Altered vascular permeability. Microaneurism. Neovascularization. Hemmorhage, scarring. Retinal detachment.
What are the risk factors for retinopathy?
Poor glycemic control, hypertension, hyperlipidemia.
What are the risk factors for vascular complications in diabetes mellitus?
Obesity. Hypertension. Hyperglycemia. Hyperinsulinemia. Hyperlipidemia. Altered platelet function. Endothelial dysfunction. Systemic inflammation. Elevated fibrinogen.
What causes diabetic foot ulcers?
Distal symmetrical neuropathy - person is unaware of “constant trauma” until overt symptoms. Deformities increase pressure points on areas not designed to withstand constant pressure. Healing is delayed due to blood glucose, decreasing blood supply.
Which types of diabetes require insulin?
Type 1 always require insulin. Most type 2 eventually require insulin.
