Chapter 25 - Endocrine Flashcards
most common endocrine disorder/disease
diabetes mellitus
most common neoplasm of endocrine system
thyroid cancer
what structures control both lobes of pituitary gland?
hypothalamus
pituitary anterior lobe hormones (2) AKA: tropic hormones
-growth hormone
-prolactin
pituitary posterior lobe hormone
-oxytocin
what are the most common tumors affecting pituitary glands
adenomas of the anterior pituitary
most adenomas are functioning tumors meaning
they produce hormones; in excess, but only ONE
mass effect of tumor
-pressure on nearby structures
-intracranial pressure
stalk effect of tumor
-tumor blocks delivery of dopamine to anterior pituitary; leads to galactorrhea
types of growth hormone overproduction (2)
-gigantism
-acromegaly
gigantism
before puberty and epiphyseal plates close; extremely tall
acromegaly
after puberty and epiphyseal plates have closed; thick bones and connective tissues
clinical manifestations of acromegaly (3)
-connective tissue proliferation: enlarge tongue, edema, coarse skin and body hair
-metabolic: abnormal glucose tolerance, hyperglycemia, hypertension, etc.
-bony proliferation: large joints, enlargement of facial bones, skull, hands and feet; protusion of lower jaw and forehead
panhypopituitarism definition
decrease in all hormones secreted by pituitary gland
cause of panhypopituitarism
destruction of anterior pituitary gland
what does panhypopituitarism cause
-atrophy of thyroid, adrenal cortex, and gonads
causes of panhypopituitarism
-large neoplasms of pituitary
-postpartum pituitary necrosis
-surgical removal of pituitary
can panhypopituitarism be lethal?
yes, if not treated
what is diabetes insipidus?
insufficiency of ADH (hormone that retains water); partial or total inability to concentrate the urine
cause of diabetes insipidus?
destruction of posterior pituitary and/or hypothalamus from
-tumors
-surgery
-hemorrhage
symptoms of diabetes insipidus (2)
-polyuria
-polydipsia
thyroid gland hormones
T3 and T4; T4 inactive until converted into T3 in the tissues
what is the main function of the thyroid gland?
maintain basal metabolic rate (BMR)
what structures control the thyroid gland?
anterior pituitary/hypothalamus
what is the thyroid gland dependent on?
iodine
hypothyroidism
not enough thyroid hormones
causes of hypothyroidism
-destruction/atrophy of thyroid gland
-deficient production of thyroid-stimulating hormone (TSH) by pituitary
-iodine deficiency
-autoimmune disease = Hashimoto thyroiditis
symptoms of hypothyroidism
-weight gain
-cold body temperature
-slow reflexes
how to diagnose hypothyroidism
-blood work to test for TSH
will there be increased or decreased TSH with hypothyroidism?
increased; taking away negative feedback
acquired hypothyroidism
-lack of iodine in diet –> T3 and T4 not made (lack negative feedback to hypothalamus) –> TRH and TSH continue to be made –> thyroid enlarges in response to TSH = NON-TOXIC GOITER (goes away with supplemental iodine)
what is hyperthyroidism?
autoimmune disease where an antibody mimics TSH producing it in excess
what is the most common cause of hyperthyroidism?
Grave’s Disease
is hyperthyroidism more common in men or women?
women
symptoms of hyperthyroidism
-weight loss (increased BMR)
-warm body temp
-hyperreflexes
manifestations of hyperthyroidism
-increased HR and palpitations
-weight loss despite increased appetite
-heat intolerance
-tremor
-hyperactivity
-diarrhea
-insomnia
-exophthalmos (bug eyes)
diagnosis of hyperthyroidism
-blood test for TSH
would TSH levels be increased or decreased with hyperthyroidism
decreased
treatment for hyperthyroidism
-drugs to suppress thyroid function
-reduce thyroid tissue by surgical removal or administration of radioactive iodine
what is diabetes mellitus
group of disorders characterized by hyperglycemia
normal range of blood glucose levels
70-100 mg/dl
high blood glucose
> 125 mg/dl
pre-diabetes range of blood glucose
100-125 mg/dl
Type 1 diabetes
pancreatic beta cell destruction by an autoimmune process
type 2 diabetes
beta cell dysfunction and insulin resistance
diagnose diabetes
one of the three:
-classic symptoms and random blood glucose >200 mg/dl
-fasting blood glucose of >125
-blood glucose >200 mg/dl after OGTT (oral glucose tolerance test)
classic symptoms of diabetes (3)
-polyuria
-polydipsia
-weight loss
-change in appetite
is type 1 diabetes more common in young or older people
young
type 1 diabetes is x dependent
insulin
type 2 diabetes more common in young or old people?
old; age-associated
is type 2 insulin dependent?
no
main risk factor for type 2 diabetes
obesity around mid-section
what causes type 1 diabetes
autoimmune disease; destruction of beta cells
what gene is associated with type 1 diabetes because of genetic susceptibility?
HLA
cause of type 2 diabetes
mainly environmental interactions, but can be genetic (not HLA gene)
pre-diabetes
number of insulin-producing beta cells is starting to decline
cause of gestational diabetes
high level of placental hormones cause the pregnant woman to be less responsive to insulin
how do you manage gestational diabetes?
diet and supplement with insulin if necessary
gestational diabetes can lead to what type of not treated
Type 2
acute effects of diabetes
-polyuria
-polydipsia
-polyphagia
-urinary water loss
-ketoacidosis
what is diabetic ketoacidosis
elevation of ketones; more common in Type 1; life threatening
characterizations of ketoacidosis
-hyperventilation
-glycosuria (glucose in urine)
-acidosis (low pH)
-vomiting/nausea
-ketonuria (ketones in urine)
-osmotic diuresis
-volume depletion
acute complications of diabetes
-diabetic ketoacidosis
-hypoglycemia (below 50 mg/dl)
treat someome that is going through ketoacidosis?
give insulin
treat someone that is hypoglycemic?
no insulin; give sugar tablets
complication of hyperglycemia
glycosylation - glucose binds to proteins
effects of glycosylation
-inflammation
-thrombosis
-damage endothelial cells
-promote vascular disease
glycosylation is mainly caused by
hyperglycemia
long term effects of diabetes
-atherosclerosis
-kidney disease
-retina
-peripheral nerve disease
-infections
treatment of type 1 diabetes
insulin replacement
treatment for type 2 diabetes
-meds to increase insulin secretion or decrease hyperglycemia
-limit CHO
-exercise
-insulin
