Endocrinology_UW Flashcards
What is gastroparesis?
Delayed gastric emptying.
Diabetic autonomic neuropathy occurs in ?% of patients and how can it manifest?
Greater than 50% of patients with longstanding type 1 or 2 DM. Can manifest as esophageal motility (dysphagia), gastric emptying (gastroparesis) or intestinal function (diarrhea, constipation)
What are the symptoms of diabetic gastroparesis?
Anorexia, vomiting, nausea, early satiety, postprandial fullness and imparied glycemic control (low blood sugar levels with insulin administration prior to meals).
What meds are useful in managing diabetic gastroparesis?
Prokinetic agents such as metoclopramide (has both prokinetic and antiemetic), erythrmocyin, cisapride.
A patient with acute, severe illness with abnormal thryoid tests has what condition? It is due to?
Sick Euthyroid syndrome due to caloric deprivation and increased production of cytokine levels. **side note: thyroid function testing not usually done in such patients unless there is clinical suspicion of actual underlying thryoid disease.
What is the most common thyroid hormone pattern in such patients?
Remember “low T3 syndrome.” Fall in total and T3 levels, normal T4 and TSH levels. *Side note: decreased T3 due to less peripheral conversion of T4 to T3. If non-thyroidal illness continues then serum T4 and TSH also decrease.
Primary hyperaldosteronism is usually due to?
Adenoma or bilateral adrenal hyperplasia
What is the preferred treatment for 1) unilateral adrenal adenoma and 2) bilateral adrenal hyperplasia?
1) surgery 2) medical therapy with aldosterone antagonists (eg. Spironolactone, eplerenone)
What is eplerenone?
It is a very selective mineralocorticoid (aldosterone) antagonist with a very low affinity for progesterone or androgen receptors and therefore has fewer endocrine side effects compared to spironolactone.
What kind of side effects does spironolactone have
it is a progesterone and androgen receptor antagonist and can cause decreased libido, gynecomastia in men and breast tenderness and menstrual irreguaries in women.
Primary hypogonadism vs secondary hypogonadism - testosterone/sperm count and LH/FSH levels?
Primary: low testosterone and/or sperm count, above-normal LH and FSH. Secondary (which is central): low testosterone and/or sperm count, low or normal LH and FSH
When patients have elevated serum prolactin, serum testosterone
MRI of the pituitary
What is D5W? What it is it used to treat?
Hypotonic solution. Used to treat hypernatremia rather than hyponatremia
What are bisphosphonates used to treat?
Hypercalcemia, osteoporosis prevention, and adjunctive treatment for certain malignancies.
What is dexamethasone?
Glucocorticoid used to treat autoimmune, inflammatory and allergic conditions, and cerebral edema.
Asymptomatic patients or those with mild symptoms of SIADH is treated with?
Fluid restriction and or oral salt tablets.
Patients with severe symptoms of SIADH is treated with?
Hypertonic (3%) saline
What are the findings of SIADH?
Elevated urine omsolality. >100mOsm/kg and urine sodium >40mEq/L. Serum osmolality
What physical findings are found in hyperthryoid patients?
Goiter, hypertension, tremors involvings hands/feet, hyperreflexia, proximal muscle weakness, lid lad, afib
What should be suspected in stuporous patients with rapid breathing and a hx of weight loss, polydipsia, and polyuria.
diabetic ketoacidosis
Tests done for suspicion of DKA?
First fingerstick glucose, then chemistry, ABG, CBC
Aldosterone levels are low/normal/high in 1) central adrenal insufficiency 2) primary adrenal insufficiency?
1) central (secondary AI) levels are normal 2) primary: levels are low
Chronic supraphysiologic doses of glucocorticoids cause what kind of adrenal insufficiency? What do lab studies show?
Central (or secondary adrenal insufficiency). Lab studies show low ACTH and coristol levels and relatively normal aldosterone levels.
What do lab studies show for primary adrenal insufficiency?
Low cortisol, high ACTH, low aldosterone (therefore sodium wasting and hyponatremia, hyperkalemia).
Example of isotonic fluid?
0.9% saline
Example of hypotonic fluid?
5% dextrose preferred over 0.45% saline.
What is the preferred tx for hypovolemic hypernatremia?
IV normal saline (0.9%) - isonotic fluid
What is the preferred tx for euvolemic hypernatremia?
5% dextrose preferred over 0.45% saline.
What are the components of MEN type 2A
Medullary carcinoma of the thyroid, primary hyperparathyroidism, and pheochromocyoma
What is the recommended screening test for suspected MEN 2 syndromes?
Genetic testing (RET proto-oncogene germline mutation). More sensitive than the biochemical measurement (serum calcitonin)
What is the biohemical testing to dx pheochromocytoma?
24-hour urine for metanephrines and free catechoalmines or plasma free metanephrines to diagnose pheochromocytoma.
Components of MEN2B?
Medullary thyroid cancer, pheochromocytoma, other such as mucosal and intestinal neuromas and marfanoid habitus.
Components of MEN1?
Primary hyperparathyroidism (>90%), enteropancreatic tumors (60%-70%), pituitary tumors (10-20%)
What is the function of Vit D as it relates to calcium and phosphate ions?
Vit D increases dietary calcium and phosphate absorption, increases bone resoprtion that increases calcium and phosphate ions
Chronic GI disease like steathorrhea, celiac disease can cause vit D deficiency. Patients then usually develop?
Hypocalcemia, low phosphorus and elevated PTH (secondary hyperparathyroidism). Patients can be asymptomatic or develop bone pain/tenderness, muscle weakness or cramps, gait abnormalities.
What is doxazosin?
Alpha blocker. Used to treat high blood pressure and also BPH
What should be considered before the start of sildanefil?
1) contraindicated in patients being treated with nitrates and those hypersensitive to sildanefil 2) used with caution in patients with conditions predisposed to priapism 3) concurrent use of drugs that interfere with sildanefil metabolism (erythrmomycin, cimetidine) 4) combination with alpha blocker (liek doxazosin) - need to give drugs with at least 4 hour interval to reduce risk of hyotension.
What is the main tx for most patients with prolactinoma?
Dopamine agonists such as bromocriptine or cabergoline (newer drug with lower side effects). Same tx for micro prolactinoma (smaller than 10mm) or macroprloactinoma. Leads to normalization of prolactin levels and also reduction in tumor size.
What are examples of dopaminergic agents?
Bromocriptine and cabergoline
Elevated levels of which androgen are specifically seen in patients with androgen producing adrenal tumors?
Dehydroepiandrosterone-sulftate (DHEA-S)
What are the risk factors for diabetic foot ulcers?
Diabetic neuropathy, previous foot ulceration, vascular disease, and foot deformity. Diabetic neuropathy is the most important contributing factor and found in >80% of patients with ulcers.
What test assess patient’s risk of foot ulcers?
Monofilament testing => test for pressure sensation using a 10g monofilament (placed on plantar surface at right angle with increasing pressure until filament buckles).
What is virilization?
Development of male physical characteristics (muscle bulk, body hair, deep voice) in a female or precociously in a boy, typically due to excess androgen production.
Rapidly developing hyperandrogenism with virilzation is highly suggestive of?
Androgen secreting neoplasm of the ovary or adrenal glands.
Testing for what levels is helpful in delineating site of excess androgen production?
Testosterone and DHEA-S. High levels of testosterone with normal levels of DHEA-S suggests ovarian source of androgens. High levels of DHEA-s with normal testosterone levels suggests adrenal source.
Untreated hyperthryoid patients are at risk for developing?
Rapid bone loss due to increased osteoclastic activity in the bone cells and also for cardiac tachyarrhythmias, including afibrillation.
Increased thryoid hormone levels with suppressed TSH levels, selective radioactie iodine scan suggests dx of?
Toxic adenoma. Toxic adenoma presents with symptoms suggestive of thyroid toxicosis.
What is hypercalcemia of immobilization?
Unclear underlying mechanism but likely due to increased osteoclastic bone resorption. Risk is increased in immobilized patients with high bone turnover(young individuals, older individuals with paget’s disease). Onset of hypercalcemia depends on the balance between the magnitude of bone turover and renal calcium excretion but th emedian onset is around 4 weeks after immobilization.
What is used to reduce hypercalcemia and prevent osteopenia in immobilized patients?
Bisphosphonate therapy and hydration.
What is the preferred initial screening test for primary hyperaldosteronism
Plasma aldosterone concentration/plasma renin activity. Ratio of greater than 20 with plasma aldosterone >10ng/dL suggests primary hyperaldosteronism.
What tests can confirm diagnosis of primary hyperaldosteronism?
Adrenal suppression testing which usually involves salt loading and inability to suppress aldosterone.
What is the most sensitive test to distinguish between adrenal adenoma and bilateral adrenal hyperplasia in patients without discrete unilateral adrenal mass on imaging?
Adrenal venous sampling
What is the immediate treatment of choice for patients with symptomatic moderate (12-14mg/dL) or severe hypercalcemia (>14mg/dL)?
IV saline hydration. It helps restore intravascular volume and promotes urinary calcium excretion.
What other treatments are used for hypercalciemia?
Calicotonin reduces serum calcium concentration within 4-6 hours and should be administered with IV saline. Bisphosphonates are recommended for long-term management in addition to tx of underlying cause.
What are the symptoms of significant hyperalcemia?
Polyuria, polydipsia, nausea, vomiting and constipation
Hypercalcemia of malignancy can be due to what?
Increased tumor production of PTH-rP (90% of malignancy induced hyperalcemia), osteolytic metastasis with local cytokine production (IL-6 levels, IL-3, Rank-L, TNF-alpha, macrophage inflammatory factor 1-a), increased tumor production of 1,25 dihydroxyvitamin D, or ectopic PTH production.
What are the PTH levels like in hypercalcemia of malignancy?
Low/suppressed
How are serum calcium levels in hypercalcemia of malignancy vs. primary hyperparathyroidism?
Generally much higher >13mg/dL.
What happens to total body K+ stores in DKA?
depletion of K+ body stores due to osmotic diuresis even though serum K+ level may be elevated.
KNOW THE CLINICAL PRESENTATION OF DKA
Metabolic acidosis, polyuria, dehydration, decreased level of consciousness, and diffuse abdominal pain
What a patient presents with hypokalemia, alkalosis and normotension, what should be suspected? What test can be used/measured to distinguish the etiologies?
Surreptitious vomiting, Diuretic abuse, Bartter sydnrome and gitelman’s syndrome. Urine chloride concentration. All etiologies besides vomiting has high chloride concnetration.