Clinical Chemistry Flashcards

1
Q

Which of the following is considered a lipid?
a. Chylomicrons
b. LDL
c. Cholesterol
d. HDL

A

c. Cholesterol

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2
Q

In the laboratory procedure for the quantification of
HDL, the purpose of the dextran sulfate is to:
a. Precipitate all Apo A1 containing lipoproteins
b. Covert cholesterol esters to cholesterol for detection
c. Precipitate all Apo B and Apo A containing
lipoproteins
d. Precipitate all Apo B containing proteins

A

d. Precipitate all Apo B containing proteins

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3
Q

Which of the following lipoproteins is the smallest of all the lipoproteins and is composed of 50% protein?
a. HDL
b. Chylomicrons
c. LDL
d. Triglycerides

A

a. HDL

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4
Q

Which of the following would be most adversely
affected by a non-fasting sample?
a. HDL
b. LDL
c. Cholesterol
d. Triglycerides

A

d. Triglycerides

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5
Q

Which of the following apoproteins is responsible for receptor binding for IDL and the chylomicron remnant produced in fat transport?

a. Apo A1
b. Apo C
c. Apo E
d. Apo B

A

c. Apo E

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6
Q

Which of the following enzymes is found bound to
HDL and LDL in blood plasma and acts to convert
free cholesterol into cholesteryl esters?
a. Cholesterol esterase
b. Cholesterol oxidase
c. Lecithin-cholesterol acyltransferase
d. Lipase

A

c. Lecithin-cholesterol acyltransferase

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7
Q

Which of the following blood samples would serve
best to assay lipoproteins because this anticoagulant
acts to preserve lipoproteins?
a. EDTA plasma sample
b. Heparin plasma sample
c. Citrate plasma sample
d. Fluoride plasma sample

A

a. EDTA plasma sample

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8
Q

Exogenous triglycerides are transported in the
plasma in which of the following forms?
a. VLDL
b. Chylomicrons
c. LDL
d. Cholesteryl esters

A

b. Chylomicrons

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9
Q

A patient presents to his physician for a lipid profile.
The following results are received:
HDL1⁄450 mg/dL
Total cholesterol1⁄4300 mg/dL Triglycerides1⁄4200 mg/dL
The calculated LDL cholesterol is:
a. 200
b. 210
c. 290
d. 350

A

b. 210

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10
Q

According to the National Cholesterol Education
Program, which lipid or lipoprotein class is more
important for therapeutic decision making (diet
and medication decisions)?
a. Chylomicrons
b. LDL
c. HDL
d. Cholesterol

A

b. LDL

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11
Q

Which of the following mechanisms accounts for the elevated plasma level of b-lipoproteins seen in hyperbetalipoproteinemia (Fredrickson’s type II lipoproteinemia)?
a. Elevated insulin found in these patients
b. Apo B-100 receptor defect
c. Apo C-II–activated lipase deficiency
d. LCAT deficiency

A

b. Apo B-100 receptor defect

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12
Q

Which enzyme is common to all enzymatic methods
for triglyceride measurement?
a. Glycerol phosphate oxidase
b. Glycerol phosphate dehydrogenase
c. Pyruvate kinase
d. Glycerol kinase

A

d. Glycerol kinase

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13
Q

A patient sample is assayed for fasting triglycerides and a triglyceride value of 1036 mg/dL. This value is of immediate concern because of its association with which of the following conditions?
a. Coronary heart disease
b. Diabetes
c. Pancreatitis
d. Gout

A

c. Pancreatitis

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14
Q

Which of the following apoproteins is inversely related to risk for coronary heart disease and is a surrogate marker for HDL?
a. Apo A-I
b. Apo B
c. Apo B100
d. APO E

A

a. Apo A-I

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15
Q

What is the most appropriate fasting procedure when a lipid study of triglycerides, total cholesterol, HDL,
and LDL tests are ordered?
a. 8 hours, nothing but water allowed
b. 10 hours, water, smoking, coffee, tea (no sugar or cream) allowed
c. 12 hours, nothing but water allowed
d. 16 hours, water, smoking, coffee, tea (no sugar or
cream) allowed

A

c. 12 hours, nothing but water allowed

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16
Q

John Smithers (21 years of age) is in to see his physician for a pre-college physical and checkup. John has always been extremely healthy. The following
laboratory results are received:
AStandard1⁄40=679 AControl1⁄40=650
ASmithers1⁄40=729 CStandard1⁄4=200 mg/dL
Control range 190-195 mg/dL
John’s cholesterol concentration is approximately:
a. 186 mg/dL
b. 199 mg/dL
c. 209 mg/dL
d. 215 mg/dL

A

c. 209 mg/dL

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17
Q

Sucrose is considered a disaccharide that on hydrolysis yields which of the following sugars?
a. Glucose
b. Galactose and glucose
c. Maltose and glucose
d. Fructose and glucose

A

d. Fructose and glucose

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18
Q

Laboratory tests are performed for a postmenopausal, 57-year-old woman as part of an annual physical examination. The patient’s random serum glucose is 220 mg/dL, and the glycated hemoglobin (HbA1c) is 11%. Based on this information, this
patient would mostly likely be classified as:
a. Normal
b. Impaired
c. Having type 1 diabetes
d. Having type 2 diabetes

A

d. Having type 2 diabetes

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19
Q

Which of the biochemical processes below is promoted by insulin?
a. Glycogenolysis
b. Gluconeogenesis
c. Esterification of cholesterol
d. Uptake of glucose by the cells

A

d. Uptake of glucose by the cells

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20
Q

At what serum glucose concentration would glucose
begin to appear in the urine?
a. 50 mg/dL
b. 75 mg/dL
c. 100 mg/dL
d. 170 mg/dL

A

d. 170 mg/dL

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21
Q

Which of the following laboratory tests is the best marker to detect patients with diabetes who are at
risk for developing diabetic nephropathy?
a. Creatinine
b. BUN
c. Microalbuminuria test
d. Glucose

A

c. Microalbuminuria test

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22
Q

A 68-year-old obese woman visits her doctor reporting increased urination (especially at night), increased thirst, and increased appetite. Her glucose
on examination was 210 mg/dL (fasting). Which of the following statements best fits with the given
information above?
a. The patient most likely has type 1 diabetes mellitus
b. The patient would show a positive glucose in her urine
c. The patient would have a decreased glycated hemoglobin
d. Additional testing of this patient should include assessment of hypoglycemia

A

b. The patient would show a positive glucose in her urine

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23
Q

Which of the following hemoglobin A1c results represents an impaired state according to the American Diabetes Association?
a. 4.5%
b. 5.5%
c. 6.0%
d. 6.5%

A

c. 6.0%

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24
Q

A plasma glucose result is 100 mg/dL. The corresponding glucose in whole blood would approximate:
a. 58 mg/dL
b. 87 mg/dL
c. 98 mg/dL
d. 114 mg/dL

A

b. 87 mg/dL

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25
Q

Which of the following methods is virtually specific for glucose and employs G6PD as a second coupling
step requiring magnesium?
a. Hexokinase
b. Glucose oxidase
c. Glucose dehydrogenase
d. Pyruvate kinase

A

a. Hexokinase

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26
Q

A 62-year-old patient presents to the physician with report of increased thirst and increased urination,
particularly at night. The physician requests a series of tests over the next few days. The following data
are received:
Analyte
Random glucose - 186 mg/dL
Fasting glucose - 114 mg/dL
2-Hour OGTT - 153 mg/dL
HbA1c - 5.9%
Which of the following conclusions may be made regarding these data?
a. Data represents normal glucose status
b. Data represents an impaired glucose status
c. Data represents the presence of an insulinoma
d. Data represents the diagnosis of diabetes

A

b. Data represents an impaired glucose status

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27
Q

Which of the following renal conditions is associated with a recent group A b-hemolytic streptococcus
infection?
a. Kidney obstruction
b. Acute renal failure
c. Uremic syndrome
d. Acute glomerulonephritis

A

d. Acute glomerulonephritis

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28
Q

The red complex developed in the Jaffe method to determine creatinine measurements is a result of the
complexing of creatinine with which of the following?
a. Alkaline picrate
b. Diacetyl monoxide
c. Sulfuric acid
d. Sodium hydroxide

A

a. Alkaline picrate

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29
Q

The kidney is responsible for acid-base balance through the removal of H ions via four major mechanisms. Which of the following describes one of those mechanisms?
a. Reabsorption of H ions in the proximal convoluted tubule
b. Reaction of H ions with Na in the descending loop of Henle
c. Reaction of H ions with filtered bicarbonate ions
d. Reaction of H ions with ADH in the
collecting ducts

A

c. Reaction of H ions with filtered bicarbonate ions

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30
Q

Which formula is most accurate in predicting plasma osmolality?
a. Na + 2(Cl) +BUN +Glucose
b. 2(Na) + 2 (Cl) +Glucose + BUN
c. 2(Na) +Glucose/18 +BUN/2.8
d. 2(BUN) +Glucose/18 + Cl/2.8

A

c. 2(Na) +Glucose/18 +BUN/2.8

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31
Q

Which of the following statements regarding serum urea is true?
a. Levels are independent of diet
b. High BUN levels can result from necrotic liver
disease
c. BUN is elevated in pre renal as well as renal failure
d. BUN rises earlier and quicker than creatinine in renal damage

A

c. BUN is elevated in pre renal as well as renal failure

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32
Q

Osmolality can be defined as a measure of the concentration of a solution based on:
a. The number of particles present
b. The number and size of particles present
c. The density of particles present
d. The isoelectric point of a particle

A

a. The number of particles present

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33
Q

An increased osmole gap is most commonly seen in which of the following?
a. Type 2 diabetes
b. Pancreatitis
c. Presence of toxins such as ethanol and ethylene glycol
d. Liver failure

A

c. Presence of toxins such as ethanol and ethylene glycol

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34
Q

A patient with type 2 diabetes is in for a routine examination with the physician. A series of laboratory tests are performed, including calculation of an eGFR. The patient’s calculated eGFR is 64 mL/min. This result is most indicative of:
a. A normal state
b. Abnormal glucose control
c. Mild kidney damage
d. Kidney failure

A

c. Mild kidney damage

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35
Q

A healthy 28-year-old female sees her physician for a routine examination and receives a “relatively” clean
bill of health except for the results below.
Total bilirubin 2.8 mg/dL
Direct bilirubin 0.1 mg/dL
Indirect bilirubin 2.7 mg/dL
These results most likely indicate which of the following?
a. Normal bilirubin metabolism
b. Extrahepatic obstruction
c. Dubin-Johnson syndrome
d. Gilbert’s disease

A

d. Gilbert’s disease

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36
Q

Which of the following is measured using glutamate dehydrogenase and is a measure of advanced stages,
poor prognosis, and coma in liver disease?
a. Total bilirubin
b. Ammonia
c. Unconjugated bilirubin
d. Urea

A

b. Ammonia

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37
Q

In which of the following disease states would you see an elevation in total bilirubin and conjugated bilirubin only?
a. Biliary obstruction
b. Hemolysis
c. Neonatal jaundice
d. Hepatitis

A

a. Biliary obstruction

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38
Q

In which of the following conditions does no activityof glucuronyl transferase result in increased unconjugated bilirubin and kernicterus in neonates and even-
tual death within 18 months?
a. Gilbert’s disease
b. Dubin-Johnson syndrome
c. Crigler-Najjar syndrome
d. Intravascular hemolysis

A

c. Crigler-Najjar syndrome

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39
Q

As a reduction product of bilirubin catabolism, this compound is partially reabsorbed from the intestines
through the portal circulation for re-excretion by the liver. What is this compound?
a. Urobilinogen
b. Azobilirubin
c. Biliverdin
d. Urobilin

A

a. Urobilinogen

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40
Q

In the liver, bilirubin is conjugated in the presence of which of the following?
a. b-Glucuronidase
b. Bilirubin oxidase
c. Uridine diphosphate (UDP) glucuronyl transferase
d. Peroxidase

A

c. Uridine diphosphate (UDP) glucuronyl transferase

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41
Q

Hepatocellular damage may be best assessed by which of the following parameters?
a. Serum AST and ALT levels
b. GGT and ALP
c. Bilirubin, GGT, and ALP
d. Ammonia and urea

A

a. Serum AST and ALT levels

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42
Q

Which of the following conditions is caused by deficient secretion of bilirubin into the bile canaliculi?
a. Gilbert’s disease
b. Physiologic jaundice of the newborn
c. Dubin-Johnson syndrome
d. Hemolytic jaundice

A

c. Dubin-Johnson syndrome

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43
Q

Which of the following enzymes is responsible for the conjugation of bilirubin?
a. Biliverdin reductase
b. Peroxidase
c. UDP–glucuronyl transferase
d. b-Glucuronidase

A

c. UDP–glucuronyl transferase

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44
Q

Which of the following analytes is the best indicator of hepatobiliary damage?
a. AST
b. ALT
c. ALP
d. Bilirubin

A

c. ALP

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45
Q

Which of the following fractions of bilirubin in high concentrations is associated with kernicterus in
newborns?
a. Delta bilirubin
b. Unconjugated bilirubin
c. Conjugated bilirubin
d. Unconjugated and delta bilirubin

A

b. Unconjugated bilirubin

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46
Q

The characteristic laboratory finding in alcoholic cirrhosis includes:
a. Moderate elevations in AST and ALT, normal GGT, and normal ALP
b. Slight elevations in AST and ALT, marked elevations in ALP, normal GGT
c. Slight elevations in AST, ALT, and GGT and marked elevations in 50 nucleotidase
d. Slight elevations in AST and ALT (AST>ALT), marked elevations in GGT, slight elevations in ALP

A

d. Slight elevations in AST and ALT (AST>ALT), marked elevations in GGT, slight elevations in ALP

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47
Q

Which of the following liver conditions shows an increase in both conjugated bilirubin and ALP, manifests with anti-mitochondrial antibodies, and shows
a characteristic lipoprotein X on electrophoresis?
a. Hemochromatosis
b. Primary biliary cirrhosis
c. Alcoholic fatty liver
d. Hepatic tumors

A

b. Primary biliary cirrhosis

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48
Q

Which set of results is consistent with uncompensated metabolic acidosis?
a. pH 7.25, HCO3 15 mmol/L, PCO2 37 mm Hg
b. pH 7.30, HCO3 16 mmol/L, PCO2 28 mm Hg
c. pH 7.45, HCO3 22 mmol/L, PCO2 40 mm Hg
d. pH 7.40, HCO3 25 mmol/L, PCO2 40 mm Hg

A

a. pH 7.25, HCO3 15 mmol/L, PCO2 37 mm Hg

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49
Q

A patient with emphysema who has fluid accumulation in the alveolar sacs (causing decreased ventilation) is likely to be in which of the following
acid-base clinical states?
a. Respiratory alkalosis
b. Respiratory acidosis
c. Metabolic acidosis
d. Metabolic alkalosis

A

b. Respiratory acidosis

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50
Q

Which of the following buffer systems is the most important physiologic buffer system in the body?
a. Hemoglobin
b. Protein
c. Phosphate
d. Bicarbonate/carbonic acid

A

d. Bicarbonate/carbonic acid

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51
Q

To maintain electrical neutrality in the red blood cell, bicarbonate leaves the red blood cell and enters the plasma through an exchange mechanism with which of the following?
a. TCO2
b. Sodium
c. Chloride
d. Phosphate

A

c. Chloride

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52
Q

Increased PCO2 in a patient most commonly results in which of the following primary acid-base abnormalities?
a. Respiratory acidosis
b. Metabolic acidosis
c. Respiratory alkalosis
d. Metabolic alkalosis

A

a. Respiratory acidosis

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53
Q

Which of the following changes will occur with a blood gas sample exposed to room air?
a. pH increased
b. pCOO2 increased
c. pO2 decreased
d. Ionized calcium increased

A

a. pH increased

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54
Q

Which of the following is the correct collection and handling for the analysis of blood gases?
a. Plastic syringe, dry heparin, store on ice, assay within 1 hour
b. Glass syringe, liquid heparin, store on ice, assay within 15 minutes
c. Glass syringe, no additive, store on ice, assay within 15 minutes
d. Plastic syringe, dry heparin, store at room temperature, assay within 15 minutes

A

d. Plastic syringe, dry heparin, store at room temperature, assay within 15 minutes

55
Q

What is the blood pH when the partial pressure of carbon dioxide (pCO2) is 45 mm Hg and the bicarbonate is 28 mmol/L?
a. 7.00
b. 7.11
c. 7.33
d. 7.41

A

b. 7.11

56
Q

What is the normal ratio of bicarbonate to dissolved carbon dioxide in arterial blood?
a. 1:10
b. 10:1
c. 20:1
d. 1:20

A

c. 20:1

57
Q

Which of the following sets of blood gas data is considered normal?
a. pH 7.33, HCO3 18 mmol/L, pCO2 32 mm Hg
b. pH 7.30, HCO3 16 mmol/L, pCO2 28 mm Hg
c. pH 7.45, HCO3 22 mmol/L, pCO2 40 mm Hg
d. pH 7.40, HCO3 25 mmol/L, pCO2 40 mm Hg

A

d. pH 7.40, HCO3 25 mmol/L, pCO2 40 mm Hg

58
Q

Which of the following values would be seen in uncompensated metabolic acidosis?
a. pH 7.38
b. pCO2 52 mm Hg
c. HCO3 15 mmol/L
d. pH 7.53

A

c. HCO3 15 mmol/L

59
Q

Which of the following blood gas disorders is most commonly associated with an abnormal anion
gap?
a. Metabolic acidosis
b. Metabolic alkalosis
c. Respiratory acidosis
d. Respiratory alkalosis

A

a. Metabolic acidosis

60
Q

Which of the following statements best describes the predominant feedback system associated with
endocrinology?
a. Decreased levels of circulating hormones directly result in the production of hormone from the target organ
b. Increased circulating levels of hormones directly result in the production of releasing factor from the hypothalamus
c. Increased circulating levels of hormones directly result in the production of inhibiting factor from the hypothalamus
d. Normal levels of circulating hormones directly result in the production of hormone from the target organ

A

c. Increased circulating levels of hormones directly result in the production of inhibiting factor from the hypothalamus

61
Q

The following laboratory results are from a 54-year-old woman complaining of weight gain, intolerance to heat, fatigue, and not being able to stay awake.

Analyte
Na = 140 mmol/L
K = 4.0 mmol/L
Glucose = 75 mg/dL
Aldosterone = 8 ng/dL
Ionized Ca = 4.8 mg/dL
Mg = 2.0 mEq/L
Phos = 3.0 mg/dL
TSH = 7.2 mU/mL
FT4 = 1.0 ng/dL
Cortisol = 10 mg/dL

Which of the following conditions best fits with the history and data?
a. Hyperthyroidism
b. Cushing’s syndrome
c. Hyperaldosteronism
d. Hypothyroidism

A

d. Hypothyroidism

62
Q

A 42-year-old woman presents to her physician with truncal obesity, bruising, hypertension, hyperglycemia, and increased facial hair. The physician suspects an endocrine disturbance. Significant test results are as follows:
Analyte
TSH = 3.0 mU/mL
FT4 = 1.0 ng/dL
Glucose = 90 mg/dL
Serum cortisol (8 AM) = 45 mg/dLPlasma ACTH (8 AM) = 152 pg/mL
Urine free cortisol = Increased
Dexamethasone suppression tests
Overnight = 300nmol/L
High dose = >50% suppression

What is the most probable condition?
a. Pituitary tumor
b. Addison’s disease
c. Adrenal adenoma
d. Ectopic ACTH production

A

a. Pituitary tumor

63
Q

Hypothyroidism is best characterized by which of the following sets of test results?
a. TSH 0.2 mU/mL, FT3 8.9 pg/mL, FT4 4.5 ng/dL
b. TSH 8.5 mU/mL, FT3 1.0 pg/mL, FT4 0.5 ng/dL
c. TSH 0.1 mU/mL, FT3 1.1 pg/mL, FT4 0.8 ng/dL
d. TSH 3.9 mU/mL, FT3 3.0 pg/mL, FT4 1.0 ng/dL

A

b. TSH 8.5 mU/mL, FT3 1.0 pg/mL, FT4 0.5 ng/dL

64
Q

The release of thyroid-releasing hormone (TRH) would result in which of the following actions from
the HPT axis?
a. Decreased release of thyroid-stimulating hormone from the pituitary gland
b. Increased release of thyroid-stimulating hormone from the thyroid gland
c. Increased release of thyroid hormones from the thyroid glands
d. Increased release of thyroid hormones from the pituitary gland

A

a. Decreased release of thyroid-stimulating hormone from the pituitary gland

65
Q

A serum thyroid panel reveals an increase in total T4, normal TSH, and a normal fT4. What is the most likely cause of these results?
a. Increased thyroxine-binding protein
b. Secondary hyperthyroidism
c. Subclinical hypothyroidism
d. Subclinical hyperthyroidism

A

a. Increased thyroxine-binding protein

66
Q

Thyroid hormones are derived from which of the following?
a. Histidine
b. Cholesterol
c. Tyrosine
d. Phenylalanine

A

c. Tyrosine

67
Q

In patients with developing subclinical hyperthyroidism, TSH levels will likely be ______, and fT4 will likely be ______.
a. Decreased, increased
b. Increased, decreased
c. Decreased, normal
d. Increased, normal

A

c. Decreased, normal

68
Q

A 30-year-old woman is admitted to the hospital. She has truncal obesity, buffalo humpback, moon face, purple striae, hypertension, hyperglycemia, increased facial hair and amenorrhea. The physician orders endocrine testing. The results are as follows:

Analyte
Urine free cortisol = Increased
Serum cortisol (8 AM) = Increased
Plasma ACTH = Decreased
Dexamethasone suppression test:
Overnight suppression = No
High dose suppression = No
What is the most probable condition?
a. Addison’s disease
b. Cushing’s disease
c. Conn’s syndrome
d. Cushing’s syndrome

A

d. Cushing’s syndrome

69
Q

Trophic hormones are produced by the ______, and releasing factors are produced by the ______.
a. Hypothalamus; pituitary
b. Pituitary; hypothalamus
c. Specific endocrine glands; hypothalamus
d. Pituitary; target gland

A

b. Pituitary; hypothalamus

70
Q

When free thyroxine cannot be measured directly, the free thyroxine index (FT4I) may be calculated by using which measured laboratory data?
a. TSH and T3 resin uptake
b. T4 and T3 resin uptake
c. TSH and T4
d. T3 and T3 resin uptake

A

b. T4 and T3 resin uptake

71
Q

The most commonly used challenge test to assist in evaluating a potential growth hormone deficiency is the:
a. Insulin challenge test
b. Dexamethasone suppression test
c. Oral glucose tolerance test
d. Captopril suppression test

A

b. Dexamethasone suppression test

72
Q

Symptoms of primary adrenal insufficiency (Addison’s disease) include which of the following?
a. Hypercortisolism
b. Hypokalemia
c. Hypertension
d. Acidosis

A

a. Hypercortisolism

73
Q

A TRH stimulation test is performed, and a flat response is received from this test procedure. This most likely indicates:
a. Secondary hypothyroidism
b. Tertiary hypothyroidism
c. Primary hypothyroidism
d. Secondary hyperthyroidism

A

b. Tertiary hypothyroidism

74
Q

The first step in the synthesis of thyroid hormones is:
a. Iodide trapping
b. Binding of thyroglobulin
c. Oxidation of iodine
d. Oxidation of TG molecule

A

a. Iodide trapping

75
Q

Which of the following conditions is a result of catecholamine excess, includes two classifications (MEN 1 and MEN 2), and may result in death from severe cardiovascular complications?
a. Cushing’s syndrome
b. Conn’s syndrome
c. Addison’s disease
d. Pheochromocytoma

A

a. Cushing’s syndrome

76
Q

The main estrogen produced by the ovaries and used to evaluate ovarian function is:
a. Estriol
b. Estradiol
c. Epiestriol
d. Estrogen

A

b. Estradiol

77
Q

The Michaelis-Menten theory states which of the following?
a. E + S + I <–> ES +EI + ESI –> E+P
b. E + S <–> ES –> E+P
c. E + S + I –> ES +EI –> E+P
d. E <–> ES –> E+P

A

b. E + S <–> ES –> E+P

78
Q

Which of the following enzymes is the best indicator of pancreatic function?
a. AST
b. ALT
c. GGT
d. Lipase

A

d. Lipase

79
Q

Which of the following enzymes catalyzes the conversion of p-nitrophenyl phosphate to a colored p-
nitrophenol product?
a. AST
b. ALT
c. ALP
d. GGT

A

c. ALP

80
Q

One international unit of enzyme activity is the amount of enzyme that under specified reaction conditions of substrate concentration, pH, and temperature, causes usage of
substrate at the rate of:
a. 1 millimole/min
b. 1 micromole/min
c. 1 nanomole/min
d. 1 picomole/min

A

b. 1 micromole/min

81
Q

A physician calls to request a CK test on a sample already in the laboratory for coagulation studies. The sample is 1 hour old and has been stored at 4 degree C. The plasma shows very slight hemolysis. What is the best course of action and the reason for it?
a. Perform the CK assay because no interferent is present
b. Reject the sample because it is slightly hemolyzed
c. Reject the sample becauseit has been stored toolong
d. Reject the sample because the citrate will interfere

A

d. Reject the sample because the citrate will interfere

82
Q

Which of the following statements regarding CK is true?
a. Levels are unaffected by strenuous exercise
b. Levels are unaffected by repeated intramuscular injections
c. Highest levels are seen in Duchenne’s muscular dystrophy
d. The enzyme is highly specific for heart injury

A

c. Highest levels are seen in Duchenne’s muscular dystrophy

83
Q

Which of the following conditions can “physiologically” elevate serum alkaline phosphatase?
a. Hyperparathyroidism
b. Diabetes
c. Third-trimester pregnancy
d. Nephrotic syndrome

A

c. Third-trimester pregnancy

84
Q

Kinetic enzymatic assays are best performed during which phase of an enzymatic reaction?
a. Linear phase
b. Lag phase
c. Plateau phase
d. Any phase as long as temperature and pH are constant

A

a. Linear phase

85
Q

A nurse calls the laboratory technologist on duty asking about blood collection for the analysis of enzymes (AST, ALP, ALT, GGT, CK). Which of the following tubes would you suggest the technologist collect?
a. Red top
b. EDTA
c. Oxalate
d. Fluoride

A

a. Red top

86
Q

Which of the following enzymes catalyzes the conversion of starch to glucose and maltose?
a. Lipase
b. Amylase
c. ALT
d. GGT

A

b. Amylase

87
Q

Hyperparathyroidism is most consistently associated with which of the following?
a. Hypocalcemia
b. Hypercalciuria
c. Hypophosphatemia
d. Metabolic alkalosis

A

c. Hypophosphatemia

88
Q

What percentage of serum calcium is in the ionized form?
a. 30%
b. 50%
c. 60%
d. 80%

A

b. 50%

89
Q

Which of the following best describes the action of parathyroid hormone?
a. PTH increases calcium and phosphorus reabsorption in the kidney
b. PTH decreases calcium and phosphorus release from bone
c. PTH decreases calcium and increases phosphorus reabsorption in the liver
d. PTH increases calcium reabsorption and decreases phosphorus reabsorption in the kidney

A

d. PTH increases calcium reabsorption and decreases phosphorus reabsorption in the kidney

90
Q

Which of the following is most likely to produce an elevated plasma potassium result?
a. Hypoparathyroidism
b. Cushing’s syndrome
c. Diarrhea
d. Hemolysis

A

d. Hemolysis

91
Q

Which of the following hormones involved in calcium regulation acts by decreasing both calcium and phosphorous?
a. PTH
b. Calcitonin
c. Vitamin D
d. Cortisol

A

b. Calcitonin

92
Q

Which of the following electrolytes is the chief plasma cation whose main function is maintaining osmotic pressure?
a. Chloride
b. Potassium
c. Sodium
d. Bicarbonate

A

c. Sodium

93
Q

Which of the following conditions is associated with hypernatremia?
a. Diabetes insipidus
b. Hypoaldosteronism
c. Diarrhea
d. Acidemia

A

a. Diabetes insipidus

94
Q

Which of the following conditions will elevate ionized calcium?
a. Diabetes mellitus
b. Hyperlipidemia
c. Acidosis
d. Alkalosis

A

c. Acidosis

95
Q

The anion gap is useful (among other things) as an inexpensive measure of quality control for which of the following analytes?
a. Blood gas analyses
b. Sodium, potassium, chloride, and total carbon dioxide
c. Calcium, phosphorus, and magnesium
d. AST, ALT, GGT, and ALP

A

b. Sodium, potassium, chloride, and total carbon dioxide

96
Q

Psuedohyperkalemia is most commonly a result of which of the following?
a. Metabolic acidosis
b. Hemolysis
c. Hyperaldosteronism
d. Hyperparathyroidism

A

b. Hemolysis

97
Q

The following results were seen on a blood sample:

Analyte
Na+ = 140 mEq/L , K+= 15.0 mEq/L
Cl- = 105 mEq/L , HCO3 = 22 mmol/L

The technologist should do which of the following?
a. Report the results
b. Repeat and check the chloride result
c. Repeat and check the Na+ result
d. Check the sample for hemolysis

A

d. Check the sample for hemolysis

98
Q

The major intracellular cation is which of the following?
a. Potassium
b. Sodium
c. Chloride
d. Bicarbonate

A

a. Potassium

99
Q

Which of the following would be a typical analyte in a clinical chemistry test?
a. Calcium
b. E. coli positivity
c. Octane
d. Food additives

A

a. Calcium

100
Q

Name five kinds of body fluids which might be used for testing in a clinical chemistry laboratory:

A

Blood, Urine, CSF, Synovial Fluid, Peritoneal Fluid, Pleural Fluid

101
Q

How should a laboratory verify the reference range it uses for a particular test?
a. Call another laboratory
b. Use the numbers from a textbook
c. Test samples from healthy people
d. Look on a medical internet site

A

c. Test samples from healthy people

102
Q

Typically, a patient test result that exceeds 3 SD of the mean value for analyte is found with a frequency of:
a. 1 in 5
b. 1 in 20
c. 1 in 100
d. Never

A

c. 1 in 100

103
Q

What type of additive is in a blood collection tube with a red cap?
a. Lithium or sodium heparin
b. Potassium EDTA
c. Thrombin
d. No additive

A

d. No additive

104
Q

Potentiometric methods are most useful for which of the following types of analytes?
a. Proteins
b. Electrolytes
c. Drugs of Abuse
b. Lipids

A

b. Electrolytes

105
Q

in a test for albumin, all the albumin reacts very rapidly with an excess of the dye bromcresol purple (BCP) to produce a colored complex. The detector is set to measure the product complex. What method is most suitable for this determination of albumin?
a. Endpoint (end-up)
b. Endpoint (end-down)
c. Rate (rate-up)
d. Rate (rate-down)

A

a. Endpoint (end-up)

106
Q

Transferrin reacts with a specific antibody to produce immune complexes. What method would be most suitable to measure the concentration of transferrin?
a. Immunoturbidimetry
b. Fluorescene
c. Potentiometry
d. None of the above

A

a. Immunoturbidimetry

107
Q

When a serum sample has intrinsic color that absorbs at the same wavelength used to detect the reaction product, what technique could help distinguish the color produced by the analyte from the intrinsic color of the sample?
a. Blanking
b. Immunotubidimentry
c. Ion-selective electrode
D. PETINIA

A

a. Blanking

108
Q

Which of the following analyses wold be done using a photometric rate reaction?
a. Measurement of lipase activity
b. Determination of albumin with the dye bromcresol green
c. Determination of potassium in the presence of excess sodium
d. None of these could be done using a rate reaction

A

a. Measurement of lipase activity

109
Q

Pretreatment is designed to do which of the following?
a. Ensure the concentration of analyte is in the measurable range
b. Remove substances that could be erroneously measured as analyte
c. Adjust the wavelength of light used for analysis
d. Introduce a fluorophore

A

b. Remove substances that could be erroneously measured as analyte

110
Q

Which of the following would not be a typical methodology for a clinical chemistry test?
a. Immunoturbidimetry
b. Microscopy
c. EMIT
d. ISE

A

b. Microscopy

111
Q

Which of the following sets of values for repeat analyses of a QC sample (target value of 50) reflects the best precision?
a. 50, 51, 52
b. 50, 52, 56
c. 48, 50, 52
d. 44, 50, 53

A

a. 50, 51, 52

112
Q

Which of the following sets of values for repeat analyses of a sample (target value of 100) shows the least bias?
a. 100, 105, 110
b. 95, 100, 105
c. 90, 95, 100
d. 90, 100, 105

A

b. 95, 100, 105

113
Q

Method A and method B for cholesterol both gives a value of 200 mg/dL for a serum sample; however, the same QC material analyzed by method A gives 185 mg/dL and by method B 212 mg/dL. What might cause this?
a. Method B is biased
b. Method A is imprecise
c. Both methods are showing a matrix effect for the QC material
d. Any of the above answers may be correct

A

c. Both methods are showing a matrix effect for the QC material

114
Q

What does method traceability mean?
a. The calibration of a method is linear
b. The method meets the required error budget
c. The method’s accuracy is linked to a certified method and/or material
d. The method does not show matrix effects

A

c. The method’s accuracy is linked to a certified method and/or material

115
Q

Which of the following analytes has the biggest allowable error budget based on CLIA accuracy ranges?
a. Albumin
c. The method’s accuracy is linked to a certified method and/or material
c. Chloride
d. Cholesterol

A

c. The method’s accuracy is linked to a certified method and/or material

116
Q

Which of the following is an example of prea-nalytical error?
a. Test method incorrectly calibrated
b. collection of blood in wrong kind of tube
c. Presence of interfering substance in specimen
d.Delay in sending the report to the provider

A

b. collection of blood in wrong kind of tube

117
Q

Which type of analytical error can be prevented by a good quality control program?
a. Instrument not properly calibrated
b. Presence of interfering substances in sample
c. Presence of bubbles in the light path of a photometric method
d. Analyte concentration so high it depletes the active reagent

A

a. Instrument not properly calibrated

118
Q

Which type of analytical error is recognized by an HIL index?
a. Instrument not properly calibrated
b. Presence of interfering substances in sample
c. Presence of bubbles in the light path of a photometric method
d. Analyte concentration so high it depletes the active reagent

A

b. Presence of interfering substances in sample

119
Q

What option(s) might be employed if a test result is above the upper limit of the test measurement range?
a. Manual dilution followed by reanalysis of the diluted sample
b. Automatic dilution and reanalysis of the sample
c. Use of a rection rate algorithm using two read window for an enzyme assay
d. Reporting the result as higher than the upper limit of the test method
e. All of the above

A

e. All of the above

120
Q

Which of the following test is a good marker of nutritional status?
a. Immunoglobulin M
b. Prealbumin
c. Ceruloplasmin
d. Lp(a)

A

b. Prealbumin

121
Q

Which test might be used to assess a person who is disoriented or confused?
a. Cholesterol
b. Ammonia
c. CRP
d. Iron

A

b. Ammonia

122
Q

Which tests might be ordered on a patient with abdominal pain to test for possible pancreatitis?
a. Amylase and lipase
b. Sodium and potassium
c. Cholesterol and triglyceride
d. C3 and C4

A

a. Amylase and lipase

123
Q

Which of these drug level would be considered toxic?
a. Alcohol at 80 mg/dL
b. Valproic acid at 50 ug/mL
c. Digoxin at 2 ng/mL
d. Acetaminophen at 250 ug/mL
e. Salicylate at 27 mg/dL

A

d. Acetaminophen at 250 ug/mL

124
Q

Which test is used as an indicator of congestive heart failure?
a. CRP
b. BNP
c. Cholesterol
d. Troponin
e. Haptoglobin

A

b. BNP

125
Q

Which of the following tests is the best monitor of diabetic glucose control over an 8-12 week period?
a. Glucose
b. Urine microalbumin
c. Hemoglobin A1c
d. Haptoglobin

A

c. Hemoglobin A1c

126
Q

The lipoprotein particle that is used to determine increased risk of coronary artery disease and to determine and monitor treatment for high cholesterol is:
a. HDL
b. LDL
c. Apolipoprotein A1
d. Chylomicrons

A

b. LDL

127
Q

Which test is the most specific for myocardial infraction?
a. LDH
b. CK
c. Troponin
d. Myoglobin

A

c. Troponin

128
Q

In which condition would TIBD be high?
a. Hemochromatosis
b. Chronic illness
c. Malnutrition
d. Iron deficiency

A

d. Iron deficiency

129
Q

If a screening TSH is high, which test is likely to be ordered next?
a. Cholesterol
b. Free T4
c. Ferritin
d. Glucose

A

b. Free T4

130
Q

When the kidneys are not functioning properly to filter blood and rid the body of wastes which of these test results would be most likely to occur?
a. GFR = 100 mL/min
b. High blood creatinine
c. High blood albumin
d. Low blood BUN

A

b. High blood creatinine

131
Q

Which of the following units would be used for reporting glucose on a clinical chemistry laboratory report?
a. mg/dL
b. ounces/L
c. mL/L
d. All are acceptable units

A

b. ounces/L

132
Q

What would be the value of 150 mg/dL glucose reported in SI units?
a. 1.61 mmol/L
b. 8.25 mmol/L
c. 0.367 mmol/L
d. None of the above values

A

b. 8.25 mmol/L

133
Q

If total cholesterol is 4.0 mmol/L, what is the value in conventional units?
a. 154 mg/dL
b. 102 mg/dL
c. 40 mg/dL
d. None of the above

A

a. 154 mg/dL

134
Q

If the enzymatic activity of LD is 40 IU/L at 25 degree C?
a. 40 IU/L
b. 59 IU/L
c. 27 IU/L
d. Impossible to tell from information provided

A

d. Impossible to tell from information provided