ABIM Endocrinology flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

A1c diagnostic threshold

An A1c of 6.5% or higher meets a diabetes diagnostic criterion, but it should be confirmed on a separate sample unless hyperglycemia is unequivocal.

Euglycemic DKA

Diabetic ketoacidosis can occur with glucose below 250 mg/dL, especially with SGLT2 inhibitors or pregnancy; diagnosis still requires ketosis and metabolic acidosis.

Metformin renal precautions

Do not start metformin when eGFR is below 45 mL/min/1.73 m2; stop it when eGFR falls below 30, and hold it during acute illness or contrast exposure when AKI risk is high.

SGLT2 inhibitor indications

In type 2 diabetes with heart failure, chronic kidney disease, or atherosclerotic cardiovascular disease, an SGLT2 inhibitor with proven benefit is recommended independent of A1c and metformin use.

Hypoglycemia level 2

Level 2 hypoglycemia is a glucose concentration below 54 mg/dL. It is clinically important because it increases risk of severe events and usually requires immediate carbohydrate treatment.

HHS diagnostic features

Hyperosmolar hyperglycemic state shows glucose above 600 mg/dL, effective osmolality above 320 mOsm/kg, minimal ketosis, and often profound dehydration with altered consciousness.

BMI obesity classes

Obesity begins at a BMI of 30 kg/m2: class 1 is 30 to 34.9, class 2 is 35 to 39.9, and class 3 is 40 or higher.

Weight loss threshold

A 5% to 10% weight loss improves glycemia, blood pressure, and lipids; weight loss of 10% or more can produce remission of type 2 diabetes in some patients.

Friedewald LDL validity

The Friedewald equation estimates LDL cholesterol as total cholesterol minus HDL cholesterol minus triglycerides divided by five, and it is unreliable when triglycerides exceed 400 mg/dL.

Statin intensity

High-intensity statin therapy lowers LDL cholesterol by at least 50%, whereas moderate-intensity therapy lowers it by 30% to 49%; very-high-risk patients often need additional nonstatin therapy.

GLP-1 RA contraindication

Liraglutide and semaglutide are contraindicated in patients with a personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2.

Overt hypothyroidism

Overt hypothyroidism is diagnosed by an elevated TSH with a low free T4. Levothyroxine is indicated, and TSH is rechecked about six to eight weeks after dose changes.

Subclinical hypothyroidism

Subclinical hypothyroidism has an elevated TSH with a normal free T4. Treatment is usually considered when TSH exceeds 10 mIU/L, or with symptoms, pregnancy, or cardiovascular risk.

Thyroid storm treatment

Thyroid storm is treated with a beta blocker, a thionamide, iodine given after the thionamide, glucocorticoids, and supportive care for fever, dehydration, and arrhythmia.

Medullary thyroid cancer

Medullary thyroid carcinoma arises from parafollicular C cells, secretes calcitonin, and is associated with RET mutations and multiple endocrine neoplasia type 2.

Amiodarone thyroid types

Amiodarone-associated thyrotoxicosis type 1 is iodine-induced excess synthesis, while type 2 is destructive thyroiditis; type 2 often responds to glucocorticoids rather than antithyroid drugs.

Adrenal crisis treatment

Adrenal crisis requires immediate hydrocortisone 100 mg intravenously, followed by about 50 mg every six hours, plus saline and glucose resuscitation; do not delay steroids for testing.

Primary aldosteronism screen

Primary aldosteronism is screened with the aldosterone-to-renin ratio in patients with resistant hypertension, hypokalemia, or an adrenal incidentaloma; confirmatory testing follows an elevated ratio.

Pheochromocytoma biochemical test

Pheochromocytoma is best screened with plasma free metanephrines or 24-hour urine fractionated metanephrines; alpha blockade must precede beta blockade to avoid unopposed vasoconstriction.

Cushing screening tests

Cushing syndrome screening uses a 1 mg overnight dexamethasone suppression test, late-night salivary cortisol, or 24-hour urinary free cortisol; abnormal results require confirmatory and subtype testing.

Pituitary apoplexy

Pituitary apoplexy causes sudden headache, visual loss, ophthalmoplegia, and hypotension from acute pituitary hemorrhage or infarction; urgent glucocorticoids and neurosurgical evaluation are required.

PCOS Rotterdam criteria

PCOS requires two of three findings: oligo-ovulation or anovulation, clinical or biochemical hyperandrogenism, and polycystic ovaries, after excluding thyroid, prolactin, and adrenal disorders.

Menopause diagnosis

Menopause is diagnosed clinically after 12 months of amenorrhea in a woman over 45; FSH is high and estradiol low, but testing is not required when symptoms are typical.

Male hypogonadism diagnosis

Male hypogonadism requires low morning total testosterone on at least two occasions; LH and FSH distinguish primary testicular failure from secondary hypothalamic-pituitary failure.

Klinefelter syndrome

Klinefelter syndrome is 47,XXY and causes small firm testes, gynecomastia, infertility, elevated gonadotropins, and often low testosterone; testosterone replacement supports virilization and bone health.

Letrozole ovulation induction

Letrozole is first-line ovulation induction for anovulatory PCOS and often produces higher live-birth rates than clomiphene; it is also used in unexplained infertility.

Corrected calcium formula

Corrected calcium equals measured calcium plus 0.8 times (4.0 minus albumin in g/dL); this adjustment estimates calcium when albumin is low but is less reliable in critical illness.

Primary hyperparathyroidism

Primary hyperparathyroidism shows high or inappropriately normal PTH with hypercalcemia and usually low phosphate; surgery is indicated for symptoms, young age, marked hypercalcemia, kidney stones, or osteoporosis.

Hypercalcemia of malignancy

Malignancy-associated hypercalcemia usually has a suppressed PTH; PTHrP mediates many solid tumors, while myeloma and lymphoma may cause hypercalcemia through other mechanisms.

Osteoporosis T-score

Osteoporosis is defined by a DXA T-score of -2.5 or lower at the hip or spine; a T-score between -1.0 and -2.5 defines osteopenia or low bone mass.

Denosumab discontinuation

Stopping denosumab without a follow-on antiresorptive can cause rapid rebound bone loss and vertebral fractures; transition to a bisphosphonate or continue therapy is often needed.

Paget disease features

Paget disease of bone causes elevated alkaline phosphatase, bone pain, deformity, skull enlargement, and hearing loss; bisphosphonates are used for symptoms and complications.