Alterations Of Endocrine Functon Flashcards
What is the cause of type 1 diabetes mellitus?
An autoimmune response that targets the beta cells in the pancreas
Type 1 diabetes mellitus is caused by autoimmune destruction of pancreatic beta cells leads to insulin deficiency. The possible causes are genetics and environmental factors including viral infection and possibly diet.
The symptom of glycosuria in diabetes mellitus is best explained by which of the following mechanisms?
The transport maximum for glucose reabsorption is reached which stimulates the process of osmotic diuresis.
An acute insulin deficiency causes potassium to shift into cells resulting in hypokalemia.
False
The presence of insulin stimulates glucose uptake into cells. During the process of glucose uptake, potassium in transported into the cell. An acute insulin deficiency results in a decrease in glucose uptake resulting in hyperglycemia, and a decrease in potassium uptake resulting in hyperkalemia.
Why do individuals with type I diabetes mellitus sometimes produce excess ketones?
Insulin deficiency leads to the uncontrolled breakdown of fat/lipids in adipose tissue.
Bobby Davies, a 12-year-old male, is newly diagnosed with type 1 diabetes mellitus (DM). His blood glucose level is 280 mg/dL (normal - 70-110 mg/dL). The signs and symptoms of DM you would expect Bobby to exhibit include:
polydipsia and polyuria.
What is a risk factor for hypoglycemia among type 1 diabetics?
Taking insulin and not eating
Insulin decreases plasma glucose levels and therefore can potentially cause hypoglycemia.
Type 1 diabetics who experience repeated episodes of hypoglycemia often miss the early warning signs of hypoglycemia because:
the early autonomic warning signs are not activated.
Nineteen-year-old Susan Lee has type 1 diabetes mellitus. She is admitted to the hospital with the following lab values: plasma glucose 500 mg/dl (high); urine glucose 4+ (high); arterial pH 7.20 (low). Her parents state that she has been sick with the “flu” for a week. Which of the following statements best explains her circumstances?
The stress of her viral illness has caused ketoacidosis.
Elevated plasma glucose, glycosuria, and low blood pH is characteristic of diabetic ketoacidosis. This complication occurs in type 1 diabetics and can occur in response to severe stress, illness, omission of insulin, or taking medications that raise blood glucose levels.
Type 1 diabetes is mainly a result of genetics, whereas the causes of type 2 diabetes are strictly environmental.
False
Type 2 diabetes mellitus actually has a stronger genetic link that type 1 diabetes. Type 1 diabetes is understood to be caused by a combination of genetic and environmental factors.
The pathophysiology of type 2 diabetes mellitus (DM) involves:
down regulation of insulin receptors.
In addition to hyperglycemia, what other condition often develops in type 2 diabetics?
Dyslipidemia
Which pathophysiological feature is present in hyperosmolar hyperglycemic nonketotic syndrome (HHNKS)?
Profound dehydration
Management of diabetes mellitus involves measuring glycosylated hemoglobin (hemoglobin A1c) levels. The purpose of this test is to:
monitor long-term glucose control.
Chronic complications of type 1 and type 2 diabetes mellitus (DM) such as retinopathy and nephropathy are primarily related to:
chronic, uncontrolled hyperglycemia.
What are the 3 main consequences of insulin deficiency?
Decreased glucose uptake into cells (cell starvation in the land of plenty, Hyperglycemia)
Decreased potassium uptake into cells (K+ isn’t transported into the cell with glucose)
Fat breakdown in adipose tissue (decreased inhibition of lipolysis, it occurs unchecked)
In patients with type 1 diabetes, what clinical manifestations do patients report? And which are observed in clinic?
Patients report:
Polyuria
Polydipsia
Polyphagia
Weight loss
In clinic observe:
Glycosuria
Hypergycemia
What is diabetic ketoacidosis?
Is caused by a severe insulin deficiency leading to severe hyperglycemia and uncontrolled lipolysis.
What are the main causes of diabetic ketoacidosis?
Undiagnosed type 1 diabetes mellitus
Omission of insulin
Physiological stress
Taking medications that antagonize insulin
What is hypoglycemia?
Blood glucose level < 50-60 mg/dL
Results from getting too much insulin for the body’s current needs
What are hypoglycemia clinical manifestations?
Sympathetic nervous system (SNS) response to low blood glucose levels triggers the adrenal medulla to produce epinephrine
See tachycardia, palpitations, diaphoresis
What are late clinical manifestations of hypoglycemia?
Due to decreased CNS function (brain is largely dependent on glucose)
See confusion, headache, irritability, weakness, double vision, and later seizures and loss of consciousness
What are type 2 diabetes mellitus risk factors?
Genetics
Obesity
Age > 40 years
Ethnicity
Polycystic ovarian syndrome
Hyperinsulinemia
What conditions often develops in type 2 diabetes?
Downregulation of Insulin Receptors
Decreased glucose uptake into cells
Development of dyslipidemia
Beta cell destruction
Metabolic Syndrome
What are the clinical manifestations of type 2 diabetes?
Same as in Type 1, without the weight loss
Polyuria (increased urine output)
Polydipsia (thirst)
Glycosuria (glucose in the urine)
Hyperglycemia (high glucose in blood)
An acute insulin deficiency causes potassium to shift into cells resulting in hypokalemia.
False
What causes Diabetic ketoacidosis (DKA)?
Undiagnosed type 1 diabetes mellitus
Omission of insulin
Physiological stress
Taking medications that antagonize insulin
What causes Hypoglycemia?
Overdose of insulin (or antihyperglycemic agents)
Delayed or omitted meals after taking insulin
Increased exercise (especially without extra food)
Alcohol
What are the risk factors of Type 2 Diabetes Mellitus?
Genetics
Obesity
Age >40 years
Ethnicity
Polycystic ovarian syndrome
If insulin levels are chronically high, the individual is said to have
hyperinsulinemia.
What is Type 2 diabetes in a nutshell:
Downregulation of Insulin Receptors
Decreased glucose uptake into cells
Development of dyslipidemia
Beta cell destruction
Metabolic Syndrome
What is retinopathy?
Damaged capillaries in the retina leads to visual disturbances and blindness
What is Nephropathy?
Damaged capillaries in the kidneys leads to loss of protein in the urine and eventually chronic renal failure
What causes neuropathy?
Hyperglycemia leads to compromised perfusion of peripheral neurons.
What most directly causes the chronic microvascular and macrovascular complications of both Type 1 and Type 2 DM?
Hyperglycemia
What is Syndrome of Inappropriate Antidiuretic Hormone (SIADH)?
When the kidneys are exposed to excessive amounts of antidiuretic hormone (ADH).
What causes SIADH?
Post-surgery: see increased ADH secretion for 5 to 7 days following general anesthesia
Ectopic production by cancers (especially pulmonary)
Pulmonary infections: tuberculosis, other bacterial pneumonias
CNS disorders (head trauma, infections, stroke)
Syndrome of inappropriate ADH (SIADH) results in:
hyponatremia
reduced plasma osmolarity
Increased blood volume/ blood pressure
What is diabetes insipidus?
When the pituitary produces insufficient amounts of ADH (or the kidneys fail to respond to the ADH).
What is neurogenic Diabetes insipidus?
(a.k.a. Central)
Insufficient amounts of ADH secreted due to lesions of hypothalamus or posterior pituitary.
What causes neurogenic diabetes insipidus?
brain tumors, stroke, infections, head trauma.
What is nephrogenic diabetes insipidus?
Inadequate response to ADH due to renal tubule damage
What causes Nephrogenic diabetes insipidous?
Caused by several renal diseases and drug toxicity (e.g., lithium)
