endocrine

tamut pathophysiology

Posterior pituitary

• ADH: water absorption, reg fluid balance. controls plasma osmolality

• oxytocin: uterine contractions + milk ejection

Anterior pituitary hormones

• ACTH: stims cortisol, manages stress

• MSH: stims melanin prod

• GH: growth, cell repair, metab

• FSH: follicle + sperm growth

Positive feedback

Increases hormone release

Negative feedback

Decreases hormone release

Up-regulation

low concentration ↑ # of receptors/cell

Down-regulation

high concentration ↓ # receptors/cell

Neuroendocrine system

• the hypothalamic-pituitary axis (HPA) forms the structural and functional basis for the neuroendocrine system

• The hypothalamus and pituitary gland are connected by the stalk

Pineal gland

Secretes melatonin

Thyroid gland

Controls metabolism

Parathyroid gland

Regulates body's calcium levels

Pancreas functions

Endocrine - hormone production; Exocrine - digestive enzyme production

Insulin secretion stimulus

Blood glucose levels

Amylin

Regulates blood glucose by delaying gastric emptying and suppressing glucagon

Glucagon

• Stimulates glycogenolysis, gluconeogenesis, and lipolysis

• antagonist to insulin

• secretion promoted by dec bg levels

Ghrelin

Stimulates growth hormone release, controls appetite, and regulates insulin sensitivity

Adrenal glands location

Zona glomerulosa, fasciculata, reticularis

Adrenal gland stimulation

ACTH from pituitary gland and sympathetic nervous system during stress

Adrenal hormones

Glucocorticoids, mineralcorticoids, and androgens

SIADH s/s, tx

• s/s: thirst, impaired taste, anorexia, dyspnea on exertion, fatigue, Na 120-130 (could drop to 110-115)

• tx: fluid restriction, correct underlying cause, monitor sodium n neuro, hypertonic saline, vasopressin receptor agonists

what is SIADH

• hypersecretion of ADH

• leads to water retention, hyponatremia, and concentrated urine

DI

• s/s: polyuria, nocturia, continuous thirst, polydipsia, large bladder capacity, hydronephrosis, inability to concentrate the urine

• treatment:

  • neurogenic

    • ADH replacement, fluid, DDAVP

  • nephrogenic

    • comorbidity, d/c meds, correct lyte imbalance

neurogenic DI

• hypothalamus

• insufficient amounts of ADH

nephrogenic DI

• kidneys

• inadequate response to ADH

Gigantism

Overproduction of GH in childhood

• clinical manifestations:

  • Excessive height and growth of long bones

Acromegaly

Overproduction of GH in adulthood

• clinical manifestations:

  • Abnormal growth of hands, feet, facial features, other soft tissues

Hyperthyroidism

1. s/s:

   1. Thin hair, enlarged thyroid, tachycardia, weight loss, diarrhea, warm skin, hyperflexia, pretibial edema

2. labs: inc T4, inc T3, dec TSH

3. treatments: control TH prod and secretion; meds: antithyroid; surgery

Hypothyroidism

1. s/s: loss of hair, normal/small thyroid, bradycardia. Constipation, muscle weakness, edema of the extremities

2. labs: dec T4, dec T3, inc TSH

3. tx: meds, replace hormone

Hyperparathyroidism manifestations

hypercalcemia, hypophosphatemia, hypercalciuria (kidney stones), pathologic fractures

Hypoparathyroidism common cause

parathyroid damage during thyroid surgery 

diabetes type 1

• childhood diagnosed

• autoimmune destructions of insulin-producing beta cells in pancreas

• genetic predisposition

• s/s: polyuria, polydipsia, polyphagia

diabetes type 2

• adulthood diagnosed

• insulin resistance + insulin deficiency

• rf: obesity, sedentary lifestyle, genetics

• fatigue, frequent infections, thirst

polydipsia

excessive thirst or fluid intake

polyuria

excessive prod of urine

polyphagia

excessive hunger or inc appetite

Acute complications of diabetes

• hypoglycemia rapid onset

• diabetic ketoacidosis (DKA)

• HHNKS

Diabetic ketoacidosis manifestations

hyperglycemia, metabolic acidosis, ketonuria, fruit breath

Microvascular complications of diabetes

retinopathy, nephropathy, neuropathies

Cushing's

• patho: prolonged exposure to high cortisol levels

• s/s: weight gain in trunk, moon face, buffalo hump, htn, hyperglycemia

• labs: high cortisol, low ACTH, hypokalemia

• tx: surgery to remove tumor, meds to lower cortisol

addinson’s

• patho: autoimmune destruction of adrenal cortex leading to cortisol + aldosterone deficiency

• s/s: fatigue, weight loss, salt cravings, low bp

• labs: low cortisol, high ACTH, hyperkalemia

• tx: corticosteroid replacement, managing electrolytes imabalances