MKSAP 18: Endocrinology and Metabolism

Subacute thyroiditis
- radioactive iodine uptake low < 10%

tx: BB, pain control with NSAIDs

Thyrotoxicosis typically lasts 2 to 6 weeks. It is followed by a hypothyroid phase after stored thyroid hormone is depleted, typically lasting 6 to 12 weeks. The patient may become clinically hypothyroid and require temporary levothyroxine therapy. Most patients with thyroiditis eventually recover to a euthyroid state.

Potent antiresorptive drugs can cause severe hypocalcemia by impairing efflux of calcium from the skeleton in patients with ____ deficiency; it is important to assess ___ levels and correct deficiency before beginning treatment with an antiresorptive drug.vitamin D - obesity lower vitamin D levels 2/2 fat sequestration - phenobarbital and phenytoin inactivate vitamin D - glucocorticoids decrease vit D metabolism - orlistat decrease absorption - celiac disease, bariatric surgeryHigh baseline bone turnover and abrupt alteration in calcium flux between blood and bone are also features of ____ . Occurs after parathyroidectomy for primary hyperparathyroidism. It is caused by rapid influx of calcium from the blood into the skeleton.Hungry bone syndromeSigns of androgen excess such as progressive hirsutism and virilization (deepening of the voice, clitoromegaly, hirsutism, and temporal hair loss) over a short period of time in female patients suggest the diagnosis ____. Elevated DHES.*Androgen-producing adrenal or ovarian tumor* - *CT scan* of the abdomen when serum *DHES > 700* Pelvic ultrasound is recommended as the first imaging study if testosterone is above 150 ng/dL (5.2 nmol/L)The most likely diagnosis is ___ which is most often seen in critically ill hospitalized patients and is characterized by a reduced serum triiodothyronine (T3) level, low or low-normal serum thyroxine (T4 ) level, and normal or low (but detectable) serum thyroid-stimulating hormone (TSH) level.nonthyroidal illness syndrome (euthyroid sick syndrome),Following adrenalectomy for Cushing syndrome, patients require daily ___ to allow recovery from prolonged suppression due to hypercortisolism; recovery of adrenal function may take up to 1 year or longer depending on the severity of Cushing syndrome.glucocorticoid replacement therapy - hydrocortisone Fludrocortisone therapy is required following bilateral adrenalectomy.Diagnosis of hypogonadism in men which lab test?In men with specific signs and symptoms of hypogonadism, measuring an *8 AM total testosterone* level is indicated; if the testosterone level is low, a second 8 AM confirmatory testosterone level is measured. After the initial diagnosis, determination of primary or secondary hypogonadism is established by measurement of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels.Treatment with testosterone for men with hypogonadism when should levels be checked?Exogenous testosterone only in men with signs and sxs of hypogonadism and low serum testosterone Levels checked 3-6 months, goal level mid-normal range Monitor PSA and hematocrit levelIn chronic hypoparathyroidism, the goals of therapy are to eliminate symptoms while avoiding complications of therapy; monitoring ____ excretion is mandatory because ___ often limits therapy.*Urine calcium excretion* *hypercalciuria* Complications of prolonged hypercalciuria include nephrolithiasis and impaired glomerular filtration rate.Excluding glucocorticoid administration, the most common cause of adrenocorticotropic hormone (ACTH)-independent Cushing syndrome is an ____.*Adrenal tumor* Cushing syndrome: elevated 24-hour urine free cortisol level and elevated midnight salivary cortisol levelFor women with hypothyroidism adequately treated with levothyroxine before pregnancy, dosing can be empirically INCREASED/DECREASED by 30% when pregnancy is confirmed.INCREASED TSH should be measured every 4 weeks for the first half of pregnancy and around 30 weeks of gestation in all women with hypothyroidism. A TSH value in the lower half of the reference range should be targeted (equivalent to a TSH level below 2.5 µU/mL [2.5 mU/L]) both in preconception planning and during pregnancy.Criteria for gender-affirming hormone therapy?- Persistent, well-documented gender dysphoria - Capacity to make a fully informed decision - Age of majority in a given country - Control of significant medical or psychological conditions. Gender-affirmation hormone therapy limits fertility, thus reproductive options should be discussed with patients prior to initiation of hormone therapy. Gender confirmation surgery is often the last step in the treatment process for gender dysphoria - engage in at least 1 year of satisfactory social role change as well as consistent and compliant hormone treatment, unless hormone therapy is not desired or medically contraindicated.Many medications cause falsely high levels of catecholamines or metanephrines including certain that ____ inhibit norepinephrine uptake; therefore discontinuation of these agents at least 2 weeks prior to testing for pheochromocytoma is recommended.antidepressants - TCAs (nortriptyline) - SNRI (venlafaxine or duloxetine) others: - Levodopa - Buspirone, prochlorperazine, amphetamines, decongestantsWhen should metformin be discontinued?eGFR < 30 mL/min/1.73 m^2 Metformin may be continued in patients with an estimated glomerular filtration rate to 30 to 45 mL/min/1.73 m2 after consideration of risks and benefits; if metformin is continued, frequent monitoring of kidney function (every 3 months) is recommended.First line treatment for PCOS.*Oral contraceptive agents* are first-line pharmacologic therapy for hirsutism, acne, and menstrual dysfunction unless fertility is desired in a patient with polycystic ovary syndrome. Oral contraceptives that contain 30 to 35 µg of ethinyl estradiol appear to be more effective in managing hirsutism than formulations containing less ethinyl estradiol.When a pituitary tumor is incidentally noted what investigation needs to be done?1. Whether it is causing mass effect 2. Whether it is secreting excess hormone 3. Whether it has a propensity to grow and cause problems in the future Biochemical testing - 8 AM cortisol - TSH - Free T4 - FSH - Testosterone - Prolactin - IGF-1 If the tumor is not causing mass effect and there is no evidence of hormone excess, a pituitary MRI should be repeated in 6 months for a macroadenoma (≥1 cm) and 12 months for a microadenoma (<1 cm) to assess for growthWhat medication is required prior to adrenalectomy for pheochromocytoma?An α-receptor blockade with *phenoxybenzamine* or another α-blocker is required prior to adrenalectomy for pheochromocytoma to prevent potential hypertensive crisis during anesthesia induction and/or manipulation of the tumor. start 10-14 days prior to surgery____ (drug) has been shown to reduce cardiovascular-related events and all-cause mortality in patients with type 2 diabetes mellitus and cardiovascular disease.Empagliflozin (SGLT2)After ruling out pregnancy, the initial laboratory evaluation in secondary amenorrhea includes measurement of ____, ____, and ____ levels.FSH TSH Prolactin Patient presents with secondary amenorrhea, defined as absence of menses for more than 3 months in women who previously had regular menstrual cyclesTRUE/FALSE: To manage in-patient hyperglycemia, scheduled basal insulin or basal insulin plus correction insulin is appropriate for patients who are fasting or who have poor oral intake.TRUEWhat should be measured after transsphenoidal pituitary surgery that is a common complication 3-7 days following surgery?Serum sodium level Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is a common complication of pituitary surgery that may occur 3 to 7 days following surgery; treatment with fluid restriction will prevent further reduction in sodium levels.____ therapy should be used to treat hyperprolactinemia in women with irregular periods who are trying to conceive.Dopamine agonistPrimary hyperparathyroidism may be the first sign of ____ in persons with a family history of recurrent primary hyperparathyroidism and neuroendocrine tumors arising from the pancreas and tumors of the pituitary gland.multiple endocrine neoplasia syndrome 1 (MEN1)Women with type 1 or type 2 diabetes mellitus who are planning pregnancy should be counseled on the risk of development or progression of diabetic ____ ; rapid improvements in glycemic levels during pregnancy can temporarily worsen preexisting ___.retinopathy - dilated eye exam____ are recommended as first-line therapy in adult men and women on chronic glucocorticoid therapy with moderate to high fracture risk regardless of age.*Oral bisphosphonates* - alendronate High fracture risk in patients younger than 40 years is defined as by a previous osteoporotic fracture. Moderate fracture risk is defined as hip or spine bone mineral density Z score less than -3 or rapid bone loss (>10% at the hip or spine over 1 year) and continuing glucocorticoid treatment at >7.5 mg/day for >6 months.In patients with primary hyperparathyroidism who are undergoing parathyroidectomy surgery, identifying and correcting ___ is important to avoid postoperative hypocalcemia, which occurs due to rapid flux of serum calcium into bone (hungry bone syndrome).*vitamin D deficiency*TRUE/FALSE: Initial testing for subclinical Cushing syndrome is a 1-mg overnight dexamethasone suppression test; a cortisol level greater than 5 µg/dL (138 nmol/L) is considered a positive test.TRUEInitial testing for Cushing syndrome?*24 hour urine free cortisol* - not impacted by sleep or estrogen use *1 mg Dexamethasone suppresion test* - False-positive results may occur with concomitant use of medications (carbamazepine, phenytoin, and pioglitazone) that induce hepatic CYP3A4 enzymes and accelerate dexamethasone metabolism *late-night salivary cortisol* - not recommended in patients with shift work, inconsistent sleep pattern, smokerDrugs that can cause gynecomastia?Spironolactone Marijuana Alcohol 5α-reductase inhibitors H2-receptor antagonists Digoxin Ketoconazole Calcium channel blockers ACE inhibitors Antiretroviral agent Tricyclic antidepressants Selective serotonin reuptake inhibitors Gynecomastia presents as a rubbery, concentric, subareolar mass. Gynecomastia is typically bilateral and often associated with breast tenderness.Rising levothyroxine requirements in the absence of obvious medication noncompliance or inappropriate administration should alert the treating physician about ____.possible malabsorption - celiac (dermatitis herpetiformis rash) - Since levothyroxine is principally absorbed in the jejunum and ileum, any disease process affecting the small bowel can affect the fraction of an orally administered dose that is absorbed.Common causes of secondary hypogonadism?Untreated sleep apnea Exogenous testosterone administration Obesity Hyperprolactinemia Chronic opioid use Glucocorticoid use Infiltrative disease (lymphoma or hemochromatosis)The most common cause of primary amenorrhea is gonadal dysgenesis caused by chromosomal abnormalities, most commonly those associated with ____.Turner syndrome (TS) - short stature, neck webbing, hearing loss, aortic coarctation, bicuspid aortic valve - dx with karyotype analysisA ___ test consisting of the types of food that normally induce the hypoglycemia should be performed to determine the cause of postprandial hypoglycemia.*Mixed-meal test* Causes of hypoglycemia in adults without diabetes include drug or alcohol use, critical illness, hormonal deficiency, non-islet cell tumor, endogenous hyperinsulinism, accidental or intentional hypoglycemia, and prior Roux-en-Y gastric bypass surgery. Postprandial hypoglycemia can develop 2 to 3 years after Roux-en-Y gastric bypass surgeryOnce Cushing syndrome is established what should be the next measurement obtained?ACTH determine ACTH dependent versus ACTH independent ACTH dependent - Pituitary MRI, petrosal sinus sampling ACTH independent - 8 mg dexamethasone suppression test, ectopic sourceIn patients receiving thyroxine replacement therapy, initiation of ____ or ___ increases thyroxine-binding globulin levels whereas ____ reduces thyroxine-binding globulin levels; in either situation a change in thyroxine dosage may be required.*estrogen* *raloxifene* *testosterone reduces thyroxine-binding globulin* higher levothyroxine doses are often required after the initiation of estrogen or selective estrogen receptor modulating therapies (tamoxifen and raloxifene) due to an increase in serum thyroxine-binding globulin concentrations. Coffee, calcium carbonate, omeprazole decrease the absorption of thyroxine____ have been shown to reduce the risk for spine, hip, and nonvertebral fractures, and are generally well tolerated with low risk for serious adverse effects.Alendronate Risedronate Zoledronic acid Denosumab___ and ___ can significantly interfere with interpretation of the plasma aldosterone-plasma renin ratio (ARR) and therefore should be discontinued approximately 6 weeks prior to screening for primary aldosteronism.Spironolactone Eplerenone Spironolactone and eplerenone cause elevation of renin levels and hence can result in a false-negative ARR.A hemoglobin A1c goal of ____ is recommended for older adults with complex medical history and significant comorbidities.7.5% to 8% Coexisting chronic illnesses serious enough to require medications or lifestyle management and may include arthritis, cancer, heart failure, depression, emphysema, falls, hypertension, incontinence, stage 3 or worse chronic kidney disease, myocardial infarction, and stroke. These patients are expected to have "intermediate life-expectancy," high treatment burden, hypoglycemia vulnerability, and fall risk.Checkpoint inhibitors such as nivolumab, ipilimumab, and pembrolizumab have been associated with the development of hypophysitis with most patients presenting with the combination of ____, _____, and ____.Headache Pituitary enlargement Hypopituitarism____ is an autoimmune disease most commonly occurring in women during pregnancy and postpartum. It leads to pituitary enlargement, possible mass effect, and often deficiency of adrenocorticotropic hormone (ACTH).Lymphocytic hypophysitisAdrenalectomy is recommended for incidental adrenal masses with radiologic features that suggest increased risk of an adrenal malignancy such as size > ____ cm, ____ Hounsfield units, ___ contrast wash outsize >4 cm, density ≥10 Hounsfield units, and absolute contrast washout <50% at 10 minutes). Repeat abdominal CT imaging at 6 months is suggested for adrenal masses that are small (<4 cm) and have benign radiologic features.____ causes functional, reversible parathyroid hypofunction and must be excluded before a low or inappropriately normal parathyroid level is attributed to hypoparathyroidism.HypomagnesemiaFirst line therapy for toxic adenoma thyroid is ____.*Radioactive iodine (131I) therapy or surgery* patient has a particularly large goiter with compressive symptoms or if there is concern for malignancy, surgery is recommended as first-line therapy.Measuring ___ blood glucose levels may identify undetected hyperglycemia when preprandial blood glucose values are at target goal, but the hemoglobin A1c is above goal.postprandialPatients with primary hyperparathyroidism who do not undergo surgery require monitoring of serum calcium and creatinine every ____ months and bone mineral density of the lumbar spine, hip, and distal radius every ___ years.6 to 12 2 yearSubclinical hypothyroidism is characterized by a serum thyroid-stimulating hormone (TSH) level above the upper limit of the reference range and normal free thyroxine (T4) level; before making this diagnosis, however, transient elevation of serum TSH should be ruled out by ?repeating the measurement of TSH in 2 to 3 monthMost patients with biochemically confirmed primary aldosteronism should undergo ___ to confirm the source of the hyperaldosteronism.adrenal vein sampling - needed in most patients to determine the source of aldosterone secretion when imaging is unrevealing and to confirm lateralization when imaging demonstrates an adrenal adenoma, such as in this caseAntithyroid drug-related agranulocytosis affects between one in 300 and one in 500 patients taking therapy and may present with fever and sore throat; initial management includes _____*Stopping the drug and assessment of the neutrophil count* An absolute neutrophil count below 500/µL (0.5 × 109/L) confirms the diagnosis. Management of agranulocytosis may include hospitalization, broad-spectrum antibiotics, and hematopoietic growth factor therapy.Secondary hypogonadism is characterized by low testosterone level and low or inappropriately normal serum luteinizing hormone and follicle-stimulating hormone concentrations what is the diagnostic imaging?MRI pituitaryIn patients with myxedema coma, intravenous ___ should be administered before ____.hydrocortisone thyroid hormones to treat possible adrenal insufficiency.___ can erroneously increase the hemoglobin A1c level due to an increase in the proportion of older erythrocytes.Iron-deficiency anemiaTx thyroid storm?Management includes treatment of any precipitant illness - supportive care - thyrotoxicosis-directed therapy including β-adrenergic blockers (esmolol infusion) - antithyroid drug therapy - intravenous glucocorticoids, and potassium iodide. Plasmapheresis and emergent thyroidectomy are utilized in patients who cannot be sufficiently managed with medical therapy alone.Type 2 amiodarone-induced thyrotoxicosis (destructive thyroiditis) can be treated with moderate- to high-dose ___ that can be gradually tapered over 1 to 3 monthsPrednisoneCriteria metabolic surgery?Type 2 diabetes who have *class III obesity (BMI ≥ 40) independent of glycemic control and diabetes treatment regimen* Type 2 diabetes with *class II obesity (BMI 35.0-39.9) who fail to meet their glycemic goals* despite optimizing medical therapies and lifestyle modifications. In addition, patients with *class I obesity (BMI 30.0-34.9) who do not meet their glycemic goals despite optimizing medical therapy* should be considered for metabolic surgery.___ related to malabsorption or dietary factors is characterized by low 25-hydroxyvitamin D, calcium, and phosphate levels and elevated parathyroid hormone and alkaline phosphatase levels.Osteomalacia