Clinical Chemistry II, Quiz 16.

Board Review Question: Which of the following steroids is an adrenal cortical hormone?

corticosterone

Board Review Question: Patients with Cushing's syndrome exhibit

serum cortisol concentrations greater than 15 mg/dL

Board Review Question: During an evaluation of adrenal function, a patient had plasma cortisol determinations in the morning after awakening and in the evening. Laboratory results indicated that the morning value was higher than the evening concentration. This is indicative of:

a normal finding

Board Review Question The Porter-Silber method (phenylhydrazine in alcohol and sulfuric acid) involves which part of the steroid molecule?

dihydroxyacetone side chain

Board Review Question: Which family of steroid hormones is characterized by an unsaturated A ring?

estrogens

Which of the following tests for adrenal cortical hyperfunction has the greatest diagnostic sensitivity?

Urinary free cortisol

Which of the following expected laboratory results correlates with Addison's disease?

Low sodium, high potassium levels

Which of the following is a genetic disorder caused by enzyme deficiencies involved in the production of mineralocorticoids and glucocorticoids?

Congenital adrenal hyperplasia

To demonstrate diurnal variation, at what times should specimens be drawn for plasma cortisol determination?

8 a.m., 8 p.m.

Which of the following is a metabolite of epinephrine and can be measured in urine?

Vanillylmandelic acid

What is the definitive diagnosis for primary adrenal insufficiency?

Impaired response to ACTH stimulation

Which of the following specimens are collected during a petrosal sinus sampling with CRH stimulation procedure?

ACTH and cortisol

What is the screening test for the presumptive diagnosis of pheochromocytoma?

Plasma fractionated metanephrines

Which of the following is used to differentiate between an aldosterone-producing adenoma and idiopathic hyperaldosteronism?

Adrenal vein sampling

Which of the following laboratory results would warrant a patient with low blood pressure be prescribed a diuretic and placed on a low-salt diet?

Increased renin, increased aldosterone, hypernatremia, hypokalemia

Which statement below about patients with Addison's disease is true?

Serum levels of ACTH are high

Which of the following classes of compounds are derived from tyrosine and includes epinephrine, norepinephrine, and dopamine?

Catecholamines

The adrenal cortex releases which of the following?

all of the above

Cushing's syndrome is characterized by which of the following?

Corticosteroid excess (in blood)

Which one of these sets of hormones are produced by the adrenal glands?

androgens, catecholamines and steroids

A patient with Addison's disease would present with which of the following?

Low sodium, high potassium levels

Which of the following is NOT a metabolite of catecholamines?

Monoiodothyronine

Pituitary secretion of ACTH is inhibited by elevated levels of:

Cortisol.

Board Review Question: The urinary excretion product measured as an indicator of epinephrine production is:

vanillylmandelic acid

What is the diagnosis of a patient with high cortisol, high ACTH, and failure to suppress cortisol with the administration of dexamethasone?

Ectopic ACTH syndrome

Cushing's syndrome is characterized by which of the following?