Unit 5 Review

Question 1

Which of the following electrolyte measurements would be of clinical usefulness to the clinician treating patients for pregnancy-induced hypertension?

Answer 1

Magnesium

Question 2

Which of the following statements best reflects the clinical usefulness for measuring ionized or free calcium in blood?

Answer 2

It is the best indication of calcium status because it is biologically active and tightly regulated by PTH and vitamin D

Question 3

Which of the following blood drawing tubes is most appropriate for measuring magnesium?

Answer 3

Plain red top with no additives

Question 4

Which of the following reagents is used to determine the concentration of serum magnesium?

Answer 4

Methylthymol blue

Question 5

Monitoring intraoperative PTH is useful for:

Answer 5

Surgical management of primary hyperparathyroidism

Question 6

Blood levels of ionized calcium are sensitive to which of the following?

Answer 6

• pH and temperature

Question 7

Which of the following additives is preferred when drawing blood samples to measure parathyroid hormone (PTH)?

Answer 7

Potassium (3)-EDTA (K3-EDTA) because PTH is most stable using this additive

Question 8

Which of the following statements best illustrates the diagnostic criteria for primary hyperarathyroidism?

Answer 8

Detectable amounts of serum PTH concomitant with elevated total serum calcium

Question 9

Which of the following feedback mechanisms regulate the productions of 1, 25(OH) 2D3?

Answer 9

Negative feedback mechanism associated with circulating levels of calcium and inorganic phosphorus

Question 10

Which of the following is an effect of increased parathyroid secretion?

Answer 10

Increased intestinal absorption of calcium

Question 11

Which of the following laboratory results reflects a patient diagnosed with rickets as a result of a dietary deficiency of vitamin D?

Answer 11

Increased serum PINP, increased serum TRAP, and increased serum DPD

Question 12

Which of the following do calcium, phosphorus, and magnesium have in common?

Answer 12

They all exist as free or ionized forms, bound to proteins and complexes to radicals, e.g. sulfates to form salts

Question 13

A blood specimen is received in the laboratory from a maternity in the obstetric unit with blood magnesium ordered by the attending physician. The serum magnesium level is 5.0 mg/dL (RI = 1.6–2.6 mg/dL). Which of the following explains the elevated serum magnesium?

Answer 13

The patient is on magnesium sulfate intravenous infusion because she is experiencing preclampsia

Question 14

Which of the following is considered a significant problem with using biomarkers of bone turnover in the management of patients with osteoporosis in a clinical setting?

Answer 14

The measurements are affected by several preanalytical variables both controllable and uncontrollable

Question 15

Which laboratory test listed would be clinically useful to the clinician to assess patents with osteoporosis?

Answer 15

Serum NTX-1

Question 16

Which of the following laboratory results best represents a patent with Paget’s disease?

Answer 16

Decreased urinary hydroxyproline and increased serum alkaline phosphatase

Question 17

A progressive systemic skeletal disease characterized by low bone mass and micro architertural deterioration of bone tissue, with a consequent increase in bone fragility and susceptible to fracture describes which of the following disorders?

Answer 17

Osteoporosis

Question 18

Which of the following reagents is used in the colorimetric method to determine the concentration of calcium in serum?

Answer 18

Cresolpthalein complexone

Question 19

Which of the following is an example of a controllable preanalytical variable associated with specimen collection for bone biomarker testing?

Answer 19

Diet

Question 20

Pyridinoline, Carboxy, amino-terminal cross-linked telopeptide of type I collagen, and tartrate-resistant acid phosphatase are all examples of which of the following?

Answer 20

Biomarkers of resorption

Question 21

Which of the following compounds promote osteoclast formation?

Answer 21

1, 25-dihydroxy Vitamin D3

Question 22

Heat inactivation and chemical inhibiton are two method used to measure which of the following analytes?

Answer 22

Alkaline phosphatase isoenzymes

Question 23

Measuring RANK and/or RANKL may be clinically useful for assessing which of the following conditions?

Answer 23

Bone fractures

Question 24

Which of the following instruments can measure calcium, magnesium, and phosphorus in blood samples?

Answer 24

Atomic absorption spectrometer

Question 25

Biomarkers of bone formation include which of the following?

Answer 25

Osteocalcin

Question 26

What hormone is produced by the placenta?

Answer 26

- hCG

Question 27

Pituitary gigantism associated with which of the following?

Answer 27

Growth (GH) excess

Question 28

Which of the following is the principle estrogen produced by the ovaries and measured to evaluate ovarian function?

Answer 28

Estradiol

Question 29

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

Answer 29

ACTH independent

Question 30

Which of the following laboratory tests provides a valid index of glucocorticoids secretion?

Answer 30

Urinary free cortisol

Question 31

Diabetes inspidius is characterized by:

Answer 31

Copious production of urine (polyuria)

Question 32

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

Answer 32

Catecholamines

Question 33

Pheohromocytoma is a tumor arising from which of the following?

Answer 33

Neurochromaffin cells in the adrenal medulla

Question 34

Which metabolite is most often increased in carcinoid tumors?

Answer 34

5-hydroxyindolacetic acid (5-HIAA)

Question 35

Which of the following is a metabolite of catecholamine?

Answer 35

Vanillylmandelic acid (VMA)

Question 36

Thyroid hormones are derived from which of the following amino acids?

Answer 36

Tyrosine

Question 37

The designation of “high sensitivity” for select quantitative serum thyroid stimulating hormone (TSH) tests indicates which of the following?

Answer 37

The test exhibits low analytical sensitivity

Question 38

A normally functioning thyroid gland is clinically referred to as:

Answer 38

Euthyroid

Question 39

Which of the following are characteristic of serum hormone binding globulin (SHBG)?

Answer 39

Tightly bound to protein moiety, not biologically active and binds to testosterone

Question 40

The goal of early detection and treatment of neonatal hypothyroidism is to eliminate?

Answer 40

severe mental retardation associated with thyroid hormone deficiency in early infancy

Question 41

Which of the following describes the hypothalamic hormones?

Answer 41

They at as releasing hormones on the pituitary

Question 42

Unconjugated estriol (uE3) is clinically useful for identifying which of the following?

Answer 42

a fetus with Down syndrome

Question 43

Which of the following hormones is useful in identifying women with ectopic pregnancies or abnormal intrauterine pregnancies?

Answer 43

Human chorionic gonadotropin

Question 44

Oxytocin and antidiuretic hormone (ADH) are hormones that are released by the:

Answer 44

Posterior pituitary

Question 45

In the thyroid gland, which of the following is described as the secretory unit?

Answer 45

Follicle

Question 46

Pituitary secretion of ACTH is inhibited by elevated levels of:

Answer 46

Cortisol

Question 47

Tetraiodothyronine describes which of the following compounds?

Answer 47

T4 (thyroxine)

Question 48

Which of the following is described as a smooth muscle stimulant and vasoconstrictor?

Answer 48

Serotonin

Question 49

Which of the following is the principle method used to measure hormone levels in blood in many clinical laboratories?

Answer 49

Immunoassays

Question 50

Once produced, the thyroid hormones are stored as thyroglobulin in which of the following:

Answer 50

Colloid

Question 51

In a patient with suspected primary hyperthyroidism (Graves’ disease), one would expect the following laboratory serum results: total T4__________ FT4________. And TSH________.

Answer 51

Increased, increased, decreased

Question 52

Free thyroxine assays measure which of the following?

Answer 52

Only the unbound thyroxine level

Question 53

Thyroid peroxidase autoantibodies are most sensitive for detecting which thyroid disorder?

Answer 53

Autoimmune thyroid disease (Hashimoto’s thyroiditis)

Question 54

3, 5, 3’-triodothyronine is characterized as which of the following?

Answer 54

The most potent thyroid hormone

Question 55

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

Answer 55

Low blood sodium, high blood potassium levels

Question 56

Mini, little and big are all descriptors for which of the following peptides?

Answer 56

Gastrin

Question 57

Which of the following is the primary physiological role of secretin??

Answer 57

Stimulate the pancreas to secrete an increased volume of juice with high bi carbonate content

Question 58

The structure of cholecystokinin (CCK) is described as:

Answer 58

Linear polypeptide with multiple molecular forms

Question 59

Which of the following compounds key physiological action includes stimulation of insulin secretion in the presence of hyperglycemia and increasing intestinal fluid and electrolyte secretion?

Answer 59

Gastric inhibitory polypeptide

Question 60

Which of the following represents two primary functions of the GI tract?

Answer 60

Assimilation of nutrients and elimination of waste

Question 61

Transmural inflammation is associated with:

Answer 61

Crohn’s disease

Question 62

A gastrinoma is classified as which of the following?

Answer 62

Neuroendocrine tumor (NET)

Question 63

Which of the following GI disorders is characterized by a modified gut immune function?

Answer 63

Celiac disease

Question 64

Which of the following cells contain cholecystokinin (CCK)?

Answer 64

I cells from the upper small intestinal mucosa

Question 65

Which of the following laboratory analytes is tested from a patient with suspected lactose intolerance?

Answer 65

Glucose

Question 66

Which of the following is test(s) are clinically useful for assessing patients with possible mucosal blood loss?

Answer 66

Serum iron and total iron binding capacity (TIBC)

Question 67

Which of the following is a useful clinical laboratory test for bile salt malabsorption?

Answer 67

Measurement of 7a-hydroxy-4-cholesten-3-one

Question 68

Which of the following clinical laboratory tests is useful for diagnosis of peptic ulcer disease (PUD)?

Answer 68

Serum measurement of IgA, IgG, and cytotoxic-associated gene A (CagA)

Question 69

A patient with suspected protein-losing enteropathy (PLE) would have which of the following laboratory results?

Answer 69

Fecal clearance of Alpha-1-antitrypsin

Question 70

Which of the following GI peptides relaxes smooth muscles of gut, blood and genitourinary system; increases water and electrolyte secretion and stimulate the release of hormones from pancreas, gut, and hypothalamus?

Answer 70

Vasoactive intestinal polypeptide

Question 71

Which of the the following statements is correct regarding glycocholic and taurocholate acid

Answer 71

They are bile acids synthesized in the liver

Question 72

Which of the following test results are correct for a patient with Zollinger-Ellison syndrome?

Answer 72

Elevated serum gastrin, increase in basal gastric acid output

Question 73

The cutoff point for fasting serum glucose in the lactose tolerance test is > 30 mg/dL (>1.7 mmol/L). Which of the following is the correct interpretation for a patient whose fasting serum glucose is <20 mg/dL (<1.1 mmol/L)?

Answer 73

The pateint is lactose intolerant

Question 74

The consumption of nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin can lead to which of the following?

Answer 74

Helicobacter pylori disease

Question 75

Which of the following laboratory results is consistent with with protein-losing enteropathy (PLE)?

Answer 75

Hypoalbuminemia

Question 76

Scurvy is a disorder caused by a deficiency is which of the following?

Answer 76

Vitamin C

Question 77

Vitamins A, D and K are classified as:

Answer 77

Fat-soluble

Question 78

Vitamin B12 is also named?

Answer 78

Cyanocobalamin

Question 79

Which disorder is associated with vitamin B1 (thiamin) deficiency?

Answer 79

Beriberi

Question 80

A deficiency of vitamin K (menaquinone) can result in which of the following?

Answer 80

Increased clotting time

Question 81

The term associated with indirect methods for assessment of vitamin status is termed:

Answer 81

Functional assays

Question 82

Retinol is formed from which of the following vitamins?

Answer 82

Preformed vitamin A

Question 83

Insufficient amounts of vitamin A can lead to degenerative changes to the cornea, which leads to poor dark adaption, or night blindness, also known as:

Answer 83

Nyctalopia

Question 84

Vitamin D deficiency leads to which of the following conditions?

Answer 84

Rickets

Question 85

Which of the following functions as a chain-breaking antioxidant and is a pyroxyl radical scavenger the protects LDL and polyunsaturated fats in membranes from oxidation?

Answer 85

Alpha-tocopherol

Question 86

Vitamin E toxicity has been associated with which of the following?

Answer 86

An affliction of premature infants who have been exposed to high oxygen therapy and later developed retinopathy of prematurity (formerly retrolental fibroplasias)

Question 87

A direct assay for measurement of plasma phylloquinone is useful to assess:

Answer 87

Vitamin K status

Question 88

Decreased serum levels of vitamin B12 and folic acid are seen in patients with which of the following?

Answer 88

Sprue

Question 89

A pateint with megaloblastic anemia would show which of the following?

Answer 89

Decreased vitamin B12, decreased folic acid

Question 90

An individual who consumes massive amounts of vitamin C may develop kidney stones consisting of:

Answer 90

Oxalic acid

Question 91

Coenzyme A (CoA) contains which of the following?

Answer 91

Pantothenic acid

Question 92

Changes in vitamin B12 are most dramatic in tissues with the greatest rate of cell turnover because:

Answer 92

Deficiencies result in impaired DNA synthesis in any cell where chromosomal replication and division takes place

Question 93

Three natural forms of vitamin B6 are:

Answer 93

Pyridoxine (pyridoxol) (PN), pyridoxamine (PM), and pyridoxal (PL)

Question 94

A patient with presents with the following symptoms: loss of appetite generalized weakness abdominal pain and vomiting bright red tongue (glossitis) skin rash (casal’s necklace) Which of the following is associated with these symptoms?

Answer 94

Pellagra

Question 95

Measurement of vitamin B12 concentration in serum using an immunoassay is an example of which of the following?

Answer 95

Direct assay

Question 96

Which of the following is described as a nervous system ailment because of a deficiency of thiamine?

Answer 96

Beriberi

Question 97

Rickets in children of osteoporosis in adults can be minimized through dietary supplementation with which of the following?

Answer 97

Vitamin C, calcium and phosphorus

Question 98

Pellagra is associated with a deficiency of which of the following vitamins?

Answer 98

Vitamin B3

Question 99

Niacin is converted to which of the following two cofactors?

Answer 99

Nicotinamide- adenine dinucleotide and nicotinamide-adenine dinucleotide phosphate

Question 100

Which vitamin is a component of two redox coenzymes?

Answer 100

Vitamin B2