Endocrine Flashcards
Glucocorticoid side effects
Iatrogenic Cushing’s syndrome (buffalo hump, moon facies, truncal obesity, muscle wasting, thin skin, easy bruisability, osteoporosis, Acne, adrenocortical atrophy, peptic ulcers, glucose intolerance/ diabetes (if chronic); Immunosuppression, psychosis, Glaucoma, insomnia. Adrenal insufficiency when the drug is stopped after chronic use.
1 most common location for ectopic thyroid tissue
Tongue
2 main tests to evaluate thyroid status
TSH
next most valuable test is 2 - free T4.
21 α hydroxylase deficiency
Masculinization, hypotension (deion); 11Beta-hydroxylase deficiency - Hypertension, masculinization (drew).
3 toxicities of insulin
Hypoglycemia, Lipodystrophy (where you inject insulin), weight gain.
48 year-old female suffering with progressive lethargy and extreme sensitivity to cold. Most likely diagnosis
hypothyroidism (#1 Hashimoto Thyroiditis)
5 Areas of hypothalamus that regulate food intake
Paraventricular nucleus also regulates food intake. Dorsomedial nuclei and Arcuate nucleus also regulate food intake.
Lateral hypothalamus is inhibited by leptin.
Ventromedial area. Receive many inputs: GI gut distension, nutrient signals from the blood. Hormones ie leptin. Cortex sight, smell, taste.
5 categories for the diagnosis of metabolic syndrome
Waist circumference; TGAs; HDL; fasting blood glucose; BP “X = GB HAT”
50 year old female complains of double vision (bitemporal hemianopia), amenorrhea, low libido, and headaches, Galactorrhea. Most likely diagnosis
Prolactinoma, pressing optic chiasm.
A 35-year-old female presents w/ diffuse goiter and hyperthyroidism. Her relative values of TSH and thyroid hormone show
Graves Disease: ↓TSH, ↑ free T4 (Thyroid hormone) , ↑ total T4, ↑T3 uptake.
Addison’s characterized by 3 A’s
Adrenal Atrophy and Absence of hormone production (involves All 3 cortial divisions. ADDison’s = Cusing’s + Conn’s
Addison’s disease
Chronic Primary adrenal insufficiency due to adrenal atrophy or or destruction by disease (autoimmune TB, Metastiasis)
Adipocyte-generated leptin affects the hypothalamus
Inhibits lateral area, stimulates ventromedial area; -> Satiety
Adipocytes
modified fibroblasts that use GLUT-4 receptors (insulin dependent) Produce the hormone leptin which stimulates appetite and termogenesis. Store TGAs in cytosol. 80-95% triglycerides. Converted to saturated or unsaturated form. Can Synthesize small amounts of fatty acids and triglycerides from carbohydrates (like the liver). Turnover of Stored Fat (Lipases) Every 2-3 weeks.
most common tumor of the adrenal gland
Adrenal “incidentaloma” - benign,
Aldose reductase
traps glucose in cell by converting it to sorbitol
sorbitol dehydrogenase
Sorbitol is then converted to fructose using sorbitol dehydrogenase (Schwann cells, lens, retina, kidneys don’t have!). If ↑ blood levels galactose (AR) will also ® osmotically active alcohol forms.
Affect of aldosterone on potassium?
Aldosterone makes you LOSE POTASSIUM -> HYPOKALEMIA
Aldosterone
Increases salt reabsorption and potassium excretion. Acts on Principle cells of collecting tubules. Also at the sweat glands.
- Retention of salt at sweat glands prevents excess leakage of water. Increases sodium reabsorption from the gut. ↑ BP;
- ↓ Heart contractility because of increased serum sodium (opposite of digoxin).
- Pro vascular, prohypertensive, but anticontractility to a certain extent. Thus, in a patient w/ CHF, it is a good idea to give an aldosterone antagonist like spironolactone ® reverse the sodium effect on the heart (XS salt increases gradient to drive calcium out of the myocytes, reducing contractility) and also reduce afterload by reducing blood pressure.
What stimulates aldosterone release? What reduces its release?
- Stimulated by: ↑ K+, ANG II,
- Reduced by: ↓ Na2+
Anorexigenic substances
Leptin; MSH; Serotonin; Norepinephrine; CRH; Insulin; CCK. Signal that you are in a fed or alert state (↓feeding).
When should metformin be avoided?
Avoid metformin if IV contrast needed for imaging (IV contrast toxic to kidney) ® ↑ risk for lactic acidosis. Also avoid if Renal disease, Advanced liver disease or CHF.
BMI that a patient is considered obese
obese > or = 30.
overweight range BMI
BMI: 25-30 is overweight range. 18.5 to 25 is normal