Clinical chemistry- Enzymes and Cardiac Markers Flashcards

(80 cards)

1
Q
  1. An international unit (IU) of enzyme activity is the
    quantity of enzyme that:
    A. Converts 1 μmol of substrate to product per liter
    B. Forms 1 mg of product per deciliter
    C. Converts 1 μmol of substrate to product
    per minute
    D. Forms 1 μmol of product per liter
A

C. Converts 1 μmol of substrate to product
per minute

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2
Q
  1. Which of the following statements describes a
    nonkinetic enzyme assay?
    A. Initial absorbance is measured followed by a
    second reading after 5 minutes
    B. Absorbance is measured at 10-second intervals
    for 100 seconds
    C. Absorbance is monitored continuously for
    1 minute using a chart recorder
    D. Reflectance is measured from a xenon source
    lamp pulsing at 60 Hz
A

A. Initial absorbance is measured followed by a
second reading after 5 minutes

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3
Q
  1. Which of the following statements regarding
    enzymatic reactions is true?
    A. The enzyme shifts the equilibrium of the reaction
    to the right
    B. The enzyme alters the equilibrium constant of
    the reaction
    C. The enzyme increases the rate of the reaction
    D. The enzyme alters the energy difference between
    reactants and products
A

C. The enzyme increases the rate of the reaction

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4
Q
  1. Which statement about enzymes is true?
    A. An enzyme alters the Gibb’s free energy of the
    reaction
    B. Enzymes cause a reaction with a positive free
    energy to occur spontaneously
    C. An enzyme’s natural substrate has the highest Km
    D. A competitive inhibitor will alter the apparent
    Km of the reaction
A

D. A competitive inhibitor will alter the apparent
Km of the reaction

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5
Q
  1. Which substrate concentration is needed to
    achieve zero-order conditions?
    A. Greater than 99 × Km
    B. [S] = Km
    C. Less than 10 × Km
    D. [S] = 0
A

A. Greater than 99 × Km

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6
Q
  1. Which of the following statements is true?
    A. Apoenzyme + prosthetic group = holoenzyme
    B. A coenzyme is an inorganic molecule required
    for activity
    C. Cofactors are as tightly bound to the enzyme as
    prosthetic groups
    D. All enzymes have optimal activity at pH 7.00
A

A. Apoenzyme + prosthetic group = holoenzyme

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7
Q
  1. Which of the following statements about
    enzymatic reactions is true?
    A. NADH has absorbance maximas at 340
    and 366 nm
    B. Enzyme concentration must be in excess to
    achieve zero-order kinetics
    C. Rate is proportional to substrate concentration in
    a zero-order reaction
    D. Accumulation of the product increases the
    reaction rate
A

A. NADH has absorbance maximas at 340
and 366 nm

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8
Q
  1. The increase in the level of serum enzymes used to
    detect cholestatic liver disease is caused mainly by:
    A. Enzyme release from dead cells
    B. Leakage from cells with altered membrane
    permeability
    C. Decreased perfusion of the tissue
    D. Increased production and secretion by cells
A

D. Increased production and secretion by cells

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9
Q
  1. Which of the following enzymes is considered
    most tissue specific?
    A. Creatine kinase (CK)
    B. Amylase
    C. Alkaline phosphatase (ALP)
    D. Alcohol dehydrogenase (ADH)
A

D. Alcohol dehydrogenase (ADH)

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10
Q
  1. Which of the following enzymes is activated by
    calcium ions?
    A. CK
    B. Amylase
    C. ALP
    D. LD
A

B. Amylase

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11
Q
  1. Which of the following enzymes is a transferase?
    A. ALP
    B. CK
    C. Amylase
    D. LD
A

B. CK

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12
Q
  1. Which statement about methods for measuring
    LD is true?
    A. The formation of pyruvate from lactate (forward
    reaction) generates NAD+
    B. The pyruvate-to-lactate reaction proceeds at
    about twice the rate as the forward reaction
    C. The lactate-to-pyruvate reaction is optimized at
    pH 7.4
    D. The negative-rate reaction is preferred
A

B. The pyruvate-to-lactate reaction proceeds at
about twice the rate as the forward reaction

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13
Q
  1. Which condition produces the highest elevation
    of serum lactate dehydrogenase?
    A. Pernicious anemia
    B. Myocardial infarction
    C. Acute hepatitis
    D. Muscular dystrophy
A

A. Pernicious anemia

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14
Q
  1. In which condition is the LD most likely to be
    within normal limits?
    A. Hepatic carcinoma
    B. Pulmonary infarction
    C. Acute appendicitis
    D. Crush injury
A

C. Acute appendicitis

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15
Q
  1. The LD pleural fluid:serum ratio for a transudative
    fluid is usually:
    A. 3:1 or higher
    B. 2:1
    C. 1:1
    D. 1:2 or less
A

D. 1:2 or less

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16
Q
  1. In which type of liver disease would you expect the
    greatest elevation of LD?
    A. Toxic hepatitis
    B. Alcoholic hepatitis
    C. Cirrhosis
    D. Acute viral hepatitis
A

A. Toxic hepatitis

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17
Q
  1. Which of the following conditions will interfere
    with the measurement of LD?
    A. Slight hemolysis during sample collection
    B. Storage at 4°C for 3 days
    C. Storage at room temperature for 16 hours
    D. Use of plasma collected in heparin
A

A. Slight hemolysis during sample collection

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18
Q
  1. In the Oliver–Rosalki method, the reverse reaction
    is used to measure CK activity. The enzyme(s)
    used in the coupling reactions is (are):
    A. Hexokinase and G-6-PD
    B. Pyruvate kinase and LD
    C. Luciferase
    D. Adenylate kinase
A

A. Hexokinase and G-6-PD

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19
Q
  1. In the Oliver–Rosalki method for CK, adenosine
    monophosphate (AMP) is added to the substrate
    in order to:
    A. Inhibit adenylate kinase
    B. Block the oxidation of glutathione
    C. Increase the amount of ADP that is available
    D. Block the action of diadenosine pentaphosphate
A

A. Inhibit adenylate kinase

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20
Q
  1. Which substance is used in the CK assay to
    activate the enzyme?
    A. Flavin adenine dinucleotide (FAD)
    B. Imidazole
    C. N-acetylcysteine
    D. Pyridoxyl-5´-phosphate
A

C. N-acetylcysteine

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21
Q
  1. SITUATION: A specimen for CK performed
    on an automated analyzer using an optimized
    Oliver–Rosalki method gives an error flag
    indicating substrate depletion. The sample is
    diluted 1:2 and 1:4 by the serial dilution technique
    and reassayed. After correcting for the dilution,
    the results are as follows:
    1:2 Dilution = 3,000 IU/L 1:4 Dilution = 3,600 IU/L
    Dilutions are made a second time and assayed
    again but give identical results. What is the most
    likely explanation?
    A. The serum became contaminated prior to
    making the 1:4 dilution
    B. The wrong pipet was used to make one of the
    dilutions
    C. An endogenous competitive inhibitor is present
    in the serum
    D. An error has been made in calculating the
    enzyme activity of one of the two dilutions
A

C. An endogenous competitive inhibitor is present
in the serum

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22
Q
  1. SITUATION: A physician calls to request a CK
    on a sample already sent to the laboratory for
    coagulation studies. The sample is 2-hour-old
    citrated blood and has been stored at 4°C. The
    plasma shows very slight hemolysis. What is the
    best course of action and the reason for it?
    A. Perform the CK assay on the sample because no
    interferent is present
    B. Reject the sample because it is slightly hemolyzed
    C. Reject the sample because it has been stored
    too long
    D. Reject the sample because the citrate will
    interfere
A

D. Reject the sample because the citrate will
interfere

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23
Q
  1. Which of the following statements regarding total
    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

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24
Q
  1. Which of the following statements regarding the
    clinical use of CK-MB (CK-2) is true?
    A. CK-MB becomes elevated before myoglobin
    after an AMI
    B. CK-MB levels are usually increased in cases of
    cardiac ischemia
    C. CK-MB is more specific than myoglobin
    D. An elevated CK-MB is always accompanied by
    an elevated total CK
A

C. CK-MB is more specific than myoglobin

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25
25. A patient’s CK-MB is reported as 18 μg/L and the total CK as 560 IU/L. What is the CK relative index (CKI)? A. 0.10% B. 3.2% C. 10.0% D. 30.0%
B. 3.2%
26
26. In a nonmyocardial as opposed to a myocardial cause of an increased serum or plasma CK-MB, which would be expected? A. An increase in CK-MB that is persistent B. An increase in the percent CK-MB as well as concentration C. The presence of increased TnI D. A more modest increase in total CK than CK-MB
A. An increase in CK-MB that is persistent
27
27. Which statement best describes the clinical utility of plasma or serum myoglobin? A. Levels greater than 100 μg/L are diagnostic of AMI B. Levels below 100 μg/L on admission and 2–4 hours postadmission help to exclude a diagnosis of AMI C. Myoglobin peaks after the cardiac troponins but is more sensitive D. The persistence of myoglobin > 110 μg/L for 3 days following chest pain favors a diagnosis of AMI
B. Levels below 100 μg/L on admission and 2–4 hours postadmission help to exclude a diagnosis of AMI
28
28. What is the typical time course for plasma myoglobin following an AMI? A. Abnormal before 1 hour; peaks within 3 hours; returns to normal in 8 hours B. Abnormal within 3 hours; peaks within 6 hours; returns to normal in 18 hours C. Abnormal within 2 hours; peaks within 12 hours; returns to normal in 36 hours D. Abnormal within 6 hours; peaks within 24 hours; returns to normal in 72 hours
C. Abnormal within 2 hours; peaks within 12 hours; returns to normal in 36 hours
29
29. What is the typical time course for plasma TnI or TnT following an AMI? A. Abnormal within 3 hours; peaks within 12 hours; returns to normal in 24 hours B. Abnormal within 4 hours; peaks within 18 hours; returns to normal in 48 hours C. Abnormal within 4 hours; peaks within 24 hours; returns to normal in 1 week D. Abnormal within 6 hours; peaks within 36 hours; returns to normal in 5 days
C. Abnormal within 4 hours; peaks within 24 hours; returns to normal in 1 week
30
30. Which of the following is the most effective serial sampling time for ruling out AMI using both myoglobin and a cardiac specific marker in an emergency department environment? A. Admission and every hour for the next 3 hours or until positive B. Admission, 2 hours, 4 hours, and 6 hours or until positive C. Admission, 3 hours, 6 hours, and a final sample within 12 hours D. Admission and one sample every 8 hours for 48 hours
C. Admission, 3 hours, 6 hours, and a final sample within 12 hours
31
31. What is the recommended troponin T and I cutoff (upper limit of normal) for detecting myocardial infarction? A. The cutoff varies with the method of assay but should be no lower than 0.2 ng/mL B. The upper 99th percentile or lowest level that can be measured with 10% CV C. The concentration corresponding to the lowest level of calibrator used D. The highest value fitting under the area of the curve for the 95% confidence interval
B. The upper 99th percentile or lowest level that can be measured with 10% CV
32
32. Which of the following cardiac markers is consistently increased in persons who exhibit unstable angina? A. Troponin C B. Troponin T C. CK-MB D. Myoglobin
B. Troponin T
33
33. A patient has a plasma myoglobin of 10 μg/L at admission. Three hours later, the myoglobin is 14 μg/L and the troponin I is 0.02 μg/L (reference range 0–0.03 μg/L). These results are consistent with which condition? A. Skeletal muscle injury B. Acute myocardial infarction C. Unstable angina D. No evidence of myocardial or skeletal muscle injury
D. No evidence of myocardial or skeletal muscle injury
34
34. A patient has a plasma CK-MB of 14 μg/L at admission and a total CK of 170 IU/L. Serum myoglobin is 130 μg/L and TnI is 1.6 μg/L. Three hours later, the TnI is 3.0 μg/L. Which statement best describes this situation? A. This patient has had an AMI and further testing is unnecessary B. A second CK-MB and myoglobin test should have been performed at 3 hours postadmission to confirm AMI C. These results are consistent with skeletal muscle damage associated with a crush injury that elevated the CK-MB D. Further testing 6–12 hours postadmission is required to establish a diagnosis of AMI
A. This patient has had an AMI and further testing is unnecessary
35
35. SITUATION: An EDTA sample for TnI assay gives a result of 0.04 ng/mL (reference range 0–0.03 ng/mL). The test is repeated 3 hours later on a new specimen and the result is 0.06 ng/mL. A third sample collected 6 hours later gives a result of 0.07 ng/mL. The EKG showed no evidence of ST segment elevation (STEMI). What is the most likely explanation? A. A false-positive result occurred due to matrix interference B. Heparin should have been used instead of EDTA, which causes false positives C. The patient has suffered cardiac injury D. The patient has had an ischemic episode without cardiac injury
C. The patient has suffered cardiac injury
36
36. Which of the following laboratory tests is a marker for ischemic heart disease? A. CK-MB isoforms B. Myosin light chain 1 C. Albumin cobalt binding D. Free fatty acid binding protein
C. Albumin cobalt binding
37
37. Which test becomes abnormal in the earliest stage of the acute coronary syndrome? A. Myosin light chain 1 B. CK-MB isoforms C. Myoglobin D. High-sensitivity C-reactive protein
D. High-sensitivity C-reactive protein
38
38. Which statement best describes the clinical utility of B-type natriuretic peptide (BNP)? A. Abnormal levels may be caused by obstructive lung disease B. A positive test indicates prior myocardial damage caused by AMI that occurred within the last 3 months C. A normal test result (<100 pg/mL) helps rule out congestive heart failure in persons with symptoms associated with coronary insufficiency D. A level above 100 pg/mL is not significant if evidence of congestive heart failure is absent
C. A normal test result (<100 pg/mL) helps rule out congestive heart failure in persons with symptoms associated with coronary insufficiency
39
39. Which statement best describes the clinical utility of plasma homocysteine? A. Levels are directly related to the quantity of LDL cholesterol in plasma B. High plasma levels are associated with atherosclerosis and increased risk of thrombosis C. Persons who have an elevated plasma homocysteine will also have an increased plasma Lp(a) D. Plasma levels are increased only when there is an inborn error of amino acid metabolism
B. High plasma levels are associated with atherosclerosis and increased risk of thrombosis
40
40. Which of the following cardiac markers derived from neutrophils predicts an increased risk for myocardial infarction? A. Phospholipase A2 (PLA2) B. Glycogen phosphorylase BB (GPBB) C. Soluble CD40 ligand (sCD40l) D. Myeloperoxidase (MPO)
D. Myeloperoxidase (MPO)
41
41. Which of the following statements about the aminotransferases (AST and ALT) is true? A. Isoenzymes of AST and ALT are not found in humans B. Both transfer an amino group to α–ketoglutarate C. Both require NADP+ as a coenzyme D. Both utilize four carbon amino acids as substrates
B. Both transfer an amino group to α–ketoglutarate
42
42. Select the products formed from the forward reaction of AST. A. Alanine and α–ketoglutarate B. Oxaloacetate and glutamate C. Aspartate and glutamine D. Glutamate and NADH
B. Oxaloacetate and glutamate
43
43. Select the products formed from the forward reaction of ALT. A. Aspartate and alanine B. Alanine and α–ketoglutarate C. Pyruvate and glutamate D. Glutamine and NAD+
C. Pyruvate and glutamate
44
44. Which of the statements below regarding the methods of Henry for AST and ALT is correct? A. Hemolysis will cause positive interference in both AST and ALT assays B. Loss of activity occurs if samples are frozen at –20°C C. The absorbance at the start of the reaction should not exceed 1.0 A D. Reaction rates are unaffected by addition of P-5´-P to the substrate
A. Hemolysis will cause positive interference in both AST and ALT assays
45
45. Select the coupling enzyme used in the kinetic AST reaction of Henry. A. LD B. Malate dehydrogenase C. Glutamate dehydrogenase D. G-6-PD
B. Malate dehydrogenase
46
46. What is the purpose of LD in the kinetic method of Henry for AST? A. Forms NADH, enabling the reaction to be monitored at 340 nm B. Rapidly exhausts endogenous pyruvate in the lag phase C. Reduces oxaloacetate, preventing product inhibition D. Generates lactate, which activates AST
B. Rapidly exhausts endogenous pyruvate in the lag phase
47
47. Which of the following statements regarding the naming of transaminases is true? A. Serum glutamic oxaloacetic transaminase (SGOT) is the older abbreviation for ALT B. Serum glutamic pyruvic transaminase (SGPT) is the older abbreviation for AST C. SGPT is the older abbreviation for ALT D. SGOT is the newer abbreviation for AST
C. SGPT is the older abbreviation for ALT
48
48. Which statement accurately describes serum transaminase levels in AMI? A. ALT is increased 5- to 10-fold after an AMI B. AST peaks 24–48 hours after an AMI and returns to normal within 4–6 days C. AST levels are usually 20–50 times the upper limit of normal after an AMI D. Isoenzymes of AST are of greater diagnostic utility than the total enzyme level
B. AST peaks 24–48 hours after an AMI and returns to normal within 4–6 days
49
49. Which condition gives rise to the highest serum level of transaminases? A. Acute hepatitis B. Alcoholic cirrhosis C. Obstructive biliary disease D. Diffuse intrahepatic cholestasis
A. Acute hepatitis
50
50. In which liver disease is the DeRitis ratio (ALT:AST) usually greater than 1.0? A. Acute hepatitis B. Chronic hepatitis C. Hepatic cirrhosis D. Hepatic carcinoma
A. Acute hepatitis
51
51. Which of the following liver diseases produces the highest levels of transaminases? A. Hepatic cirrhosis B. Obstructive jaundice C. Hepatic cancer D. Alcoholic hepatitis
C. Hepatic cancer
52
52. Which of the following statements regarding transaminases is true? A. ALT is often increased in muscular disease, pancreatitis, and lymphoma B. ALT is increased in infectious mononucleosis, but AST is usually normal C. ALT is far more specific for liver diseases than is AST D. Substrate depletion seldom occurs in assays of serum from hepatitis cases
C. ALT is far more specific for liver diseases than is AST
53
53. Select the most sensitive marker for alcoholic liver disease. A. GLD B. ALT C. AST D. γ-Glutamyltransferase (GGT)
D. γ-Glutamyltransferase (GGT)
54
54. Which enzyme is least useful in differentiating necrotic from obstructive jaundice? A. GGT B. ALT C. 5’ Nucleotidase D. LD
D. LD
55
55. Which of the following statements about the phosphatases is true? A. They hydrolyze adenosine triphosphate and related compounds B. They are divided into two classes based upon pH needed for activity C. They exhibit a high specificity for substrate D. They are activated by Pi
B. They are divided into two classes based upon pH needed for activity
56
56. Which of the following statements regarding ALP is true? A. In normal adults, the primary tissue source is fast-twitch skeletal muscle B. Geriatric patients have a lower serum ALP than other adults C. Serum ALP levels are lower in children than in adults D. Pregnant women have a higher level of serum ALP than other adults
D. Pregnant women have a higher level of serum ALP than other adults
57
57. Which isoenzyme of ALP is most heat stable? A. Bone B. Liver C. Intestinal D. Placental
D. Placental
58
58. Which isoenzyme of ALP migrates farthest toward the anode when electrophoresed at pH 8.6? A. Placental B. Bone C. Liver D. Intestinal
C. Liver
59
59. Which statement regarding bone-specific ALP is true? A. The bone isoenzyme can be measured immunochemically B. Bone ALP is increased in bone resorption C. Bone ALP is used for the diagnosis of osteoporosis D. There are two distinct bone isoenzymes
A. The bone isoenzyme can be measured immunochemically
60
60. Which of the following statements regarding ALP is true? A. All isoenzymes of ALP are antigenically distinct and can be identified by specific antibodies B. Highest serum levels are seen in intrahepatic obstruction C. Elevated serum ALP seen with elevated GGT suggests a hepatic source D. When jaundice is present, an elevated ALP suggests acute hepatitis
C. Elevated serum ALP seen with elevated GGT suggests a hepatic source
61
61. In which condition would an elevated serum alkaline phosphatase be likely to occur? A. Small cell lung carcinoma B. Hemolytic anemia C. Prostate cancer D. Acute myocardial infarction
A. Small cell lung carcinoma
62
62. Which condition is least likely to be associated with increased serum ALP? A. Osteomalacia B. Biliary obstruction C. Hyperparathyroidism and hyperthyroidism D. Osteoporosis
D. Osteoporosis
63
63. Which substrate is used in the Bowers–McComb method for ALP? A. p-Nitrophenyl phosphate B. β-Glycerophosphate C. Phenylphosphate D. α-Naphthylphosphate
A. p-Nitrophenyl phosphate
64
64. Which of the following buffers is used in the IFCC recommended method for ALP? A. Glycine B. Phosphate C. 2-Amino-2-methyl-1-propanol D. Citrate
C. 2-Amino-2-methyl-1-propanol
65
65. A serum ALP level greater than twice the elevation of GGT suggests: A. Misidentification of the specimen B. Focal intrahepatic obstruction C. Acute alcoholic hepatitis D. Bone disease or malignancy
D. Bone disease or malignancy
66
66. In which condition is the measurement of acid phosphatase clinically useful? A. Measuring the prostatic isoenzyme to screen for prostate cancer B. Measuring the enzyme in a vaginal swab extract C. The diagnosis of hemolytic anemia D. As a marker for bone regeneration
B. Measuring the enzyme in a vaginal swab extract
67
67. Which definition best describes the catalytic activity of amylase? A. Hydrolyzes second α 1–4 glycosidic linkages of starch, glycogen, and other polyglucans B. Hydrolyzes all polyglucans completely to produce glucose C. Oxidatively degrades polysaccharides containing glucose D. Splits polysaccharides and disaccharides by addition of water
A. Hydrolyzes second α 1–4 glycosidic linkages of starch, glycogen, and other polyglucans
68
68. Which of the following amylase substrates is recommended by the IFCC? A. Starch B. Maltodextrose C. Maltotetrose D. Blocked maltohepatoside
D. Blocked maltohepatoside
69
69. How soon following acute abdominal pain due to pancreatitis is the serum amylase expected to rise? A. 1–2 hours B. 2–12 hours C. 3–4 days D. 5–6 days
B. 2–12 hours
70
70. Which of the following statements regarding the diagnosis of pancreatitis is correct? A. Amylase and lipase are as predictive in chronic as in acute pancreatitis B. Diagnostic sensitivity is increased by assaying both amylase and lipase C. Measuring the urinary amylase:creatinine ratio is useful only when patients have renal failure D. Serum lipase peaks several hours before amylase after an episode of acute pancreatitis
B. Diagnostic sensitivity is increased by assaying both amylase and lipase
71
71. Which of the following conditions is associated with a high level of S-type amylase? A. Mumps B. Intestinal obstruction C. Alcoholic liver disease D. Peptic ulcers
A. Mumps
72
72. Which of the following statements regarding amylase methods is true? A. Requires sulfhydryl compounds for full activity B. Activity will vary depending on the method used C. Amyloclastic methods measure the production of glucose D. Overrange samples are diluted in deionized water
B. Activity will vary depending on the method used
73
73. Which of the following statements regarding amylase methods is true? A. Dilution of serum may result in lower than expected activity B. Methods generating NADH are preferred because they have higher sensitivity C. Synthetic substrates can be conjugated to p-nitrophenol (PNP) for a kinetic assay D. The reference range is consistent from method to method
C. Synthetic substrates can be conjugated to p-nitrophenol (PNP) for a kinetic assay
74
74. The reference method for lipase uses olive oil as the substrate because: A. Other esterases can hydrolyze triglyceride and synthetic diglycerides B. The reaction product can be coupled to NADH generating reactions C. Synthetic substrates are less soluble than olive oil in aqueous reagents D. Triglyceride substrates cause product inhibition
A. Other esterases can hydrolyze triglyceride and synthetic diglycerides
75
75. Which statement about the clinical utility of plasma or serum lipase is true? A. Lipase is not increased in mumps, malignancy, or ectopic pregnancy B. Lipase is not increased as dramatically as amylase in acute pancreatitis C. Increased plasma or serum lipase is specific for pancreatitis D. Lipase levels are elevated in both acute and chronic pancreatitis
A. Lipase is not increased in mumps, malignancy, or ectopic pregnancy
76
76. The reference method for serum lipase is based upon: A. Assay of triglycerides following incubation of serum with olive oil B. Rate turbidimetry C. Titration of fatty acids with dilute NaOH following controlled incubation of serum with olive oil D. Immunochemical assay
C. Titration of fatty acids with dilute NaOH following controlled incubation of serum with olive oil
77
77. The most commonly employed method of assay for plasma or serum lipase is based on: A. Hydrolysis of olive oil B. Rate turbidimetry C. Immunoassay D. Peroxidase coupling
D. Peroxidase coupling
78
78. Which of the following enzymes is usually depressed in liver disease? A. Elastase-1 B. GLD C. Pseudocholinesterase D. Aldolase
C. Pseudocholinesterase
79
79. Which enzyme is most likely to be elevated in the plasma of a person suffering from a muscle wasting disorder? A. 5´-Nucleotidase B. Pseudocholinesterase C. Aldolase D. Glutamate dehydrogenase
C. Aldolase
80
80. Which enzyme is measured in whole blood? A. Chymotrypsin B. Glucose-6-phosphate dehydrogenase C. Glycogen phosphorylase D. Lipase
B. Glucose-6-phosphate dehydrogenase