Exam IV Non-nitrogen Protein, Kidney & Liver functions, Enzymes, Cardiac markers Flashcards
(98 cards)
1
Q
What is the substrate for the enzyme aspartate amino transferase (AST)?
A
aspartate
alpha ketoglutamic acid
2
Q
Creatinine is formed from the breakdown of?
A
creatine
3
Q
PSP is removed from the blood by the?
A
kidney
4
Q
What is the principle of the Berthelot reaction and what substances can cause falsely elevated values in the reaction?
A
hydrolysis of urea into ammonium carbonate by the enzyme urease; cause blue colored compound
high levels of ammonia or bilirubin
5
Q
Increased ALT values are associated with disease of?
A
liver
6
Q
What is the normal value for serum AST at 37?
A
5-35 uL
7
Q
Which anticoagulant should NOT be used for the urease testing?
A
sodium fluoride
8
Q
What is the normal percentage for the CK-MB isoenzyme?
A
less than 6%
9
Q
What reagent is used in the measurement of uric acid?
A
phosphotungstic acid
10
Q
Creatinine clearance is used to assess the rate of?
A
glomerular filtration
11
Q
Crcl equation
A
(Ucr * Vu)/(Pcr * t)
12
Q
What additional info must be know to calculate Crcl if the patient is an infant, young child or adolescent?
A
body surface area
13
Q
What is the most common endogenous substance used to assess GFR?
Exogenous substrate?
A
creatinine clearance
inulin
14
Q
Serum creatine kinase is most often used in diseases of?
A
muscle tissue
15
Q
Serum lipase levels are elevated in disease of?
A
pancreas
16
Q
Diacetyl monoxime reacts with ? to produce a yellow product?
A
urea
17
Q
What is uremia?
A
abnormal substances of urea in the blood
18
Q
What is the normal value for CK in males at 37?
A
15-160 U/L
19
Q
Three ways that can be used in the lab to measure the rate of an enzymatic reaction.
A
Multiple point assay
Continous Monitoring
Kinetic point assay
20
Q
Define the International Unit (IU)
A
quantity of enzyme that will catalyze one micromole (umol) of substrate per minute
21
Q
What is the peak absorbance of reduced NAD (NADH)?
A
340nm
22
Q
The Jaffe reaction is used to measure?
A
creatinine
23
Q
Which non-protein nitrogen component comprises the largest fraction of NPN in the blood?
A
BUN/ urea
24
Q
Which enzyme is useful in the detection of insecticide poisoning?
A
pseudocholinesterase
25
Low levels ow wchich enzyme can cause a patient to be susceptible to prolonges apnea when exposed to certain types of anesthesia?
pseudocholinesterase
26
Increased levels of LD-a and LD-5 are associated with?
liver
| acute hepatic disease
27
Gout is caused by the deposition of ? in joints and other tissues.
uric acid
28
What is the cilnical significance of a mildly elevated ALP in a teenager?
No significance: still growing
29
What is the normal ration of BUN to creatinine?
10:1 to 15:1
30
What enzyme is normally elevated during pregnancy?
alkaline phosphotase
31
L-tartate is used in the specific assay of which enzyme?
prostatic acid phosphotase
32
Which isoenzyme is detectable within 4-6 hours after a MI?
CK-MB2
33
Retention of BSP can be used to measure?
liver function
34
What substrate and coenzyme are required to measure ammonia?
alpha ketoglutarate
| NADH; coenzyme
35
What is the main way that ammonia levels are kept within normal limits?
liver takes ammonia and turns it into urea, which is eliminated in the urine
36
Amylase is an enzyme that breaks down?
starch
37
Why should hemolyzed specimens NOT be used for acid phosphotase?
rbc's contain acid phosphotase; false increase
38
Acid phosphotase is primarily associated with the disease of?
prostate
39
What is the proper treatment of serum to be assayed for ACP?
pH below 6
40
What is the substrate for alkaline phosphotase methods of analysis?
para-nitrophenol phosphase
41
In the urease method, urea is converted to ?
ammonium carbonate
42
Increased levels of serum alkaline phosphotase can indicate diseases of? ?
bone or liver
43
The enzyme responsible for the reversible oxidation of lactic acid to pyruvic acid is ?
LD; lactate dehydrogenase
44
In the creatine kinase reaction, ? is converted to ?
ATP to ADP
45
What is the end product of purine metabolism in man?
uric acid
46
Serum amylase might be expected to be increased in diseases of?
pancreas
47
Which enzyme can be used to establish the presence of semen?
acid phosphotase
48
Phenylketonuria (PKU) results from a deficiency in which enzyme?
phenylalanine hydroxylase
49
What is the substrate for the enzyme alanine aminotransferase (ALT)?
alanine
| alpha ketoglutamic acid
50
What is the source of urease used in enzymatic methods for the determination of BUN?
Jack Bean meal
51
What precaution must be taken with specimens to be used for blood ammonia determinations?
use plasma
avoid in vitro formation
correct tube
place on ice and test within 15 minutes
52
What is the correct order of migration of the CK isoenzymes?
MM, MB, BB
| slow - fast
53
What are the substrates for amylase in the dye labeled substrate method?
dye, starch
54
In the creatinine method, a color develops when creatinine combines with ?
alkaline picrate
55
The major isoenzymes of lactate dehydrogenase come from the ? and the ?
heart, liver
56
What is the principle of the enzymatic method for measurement of ammonia?
rxn followed by decrease in absorbance at 340 nm as NADPH is converted to NADP
uses enzyme glutamate dehydrogenase and substrate alpha ketoglutarate
57
Strenuous exercise can cause elevated ??
CK - creatine kinase
58
What causes the BSP dye to turn from colorless to colored?
alkali medium
59
What would hemolysis do to the results of a lactate dehydrogenase (LD) measurement?
How are results affected if specimen if frozen?
Increase
| cannot freeze, false decrease
60
What test can differentiate between liver and bone origin of an elevated alkaline phosphotase?
GGT
61
What is the best anticoagulant to use for plasma specimens to be tested for lactate dehydrogenase?
heparin
62
What is the order of migration for the isoenzymes of alkaline phosphotase(ALP)?
liver(fast), bone, plasma, intestinal
63
What is the characteristic change in the isoenzyme of lactate dehydrogenase (LD) that is seen in a myocardial infarction?
LD flip, 1 becomes greater than 2
64
Creatinine excretion correlates best with ??
muscle mass
65
Which enzyme is the first to become elevated following an MI?
CK-MB1
66
Aspartate aminotransferase(AST) is elevated in disease of?
heart
67
For how long and at what temp should specimens for LD be stored?
2-3 days at room temp
68
In the performance of a CRcl, when should the specimen for serum creatinine be collected in relation to the collection of the urine?
midway thru collection
| no longer than 24 hours before or after collection
69
What enzyme can ce used in the detection of alcoholism and in the monitoring of patients in alcohol treatment centers?
GGT; gamma glutamytransferase
70
What is the normal value for prostatic acid phosphotase(ACP)?
less than 2.1 ng/mL
71
Why are creatinine levels in the serum not a good indicator of early renal damage?
Increased levels are not abnormal until 1/2 to 2/3 of renal function is abnormal
72
What is the composition of Nessler's reagent and for what test is it used?
double iodide of potassium/mercury
| BUN
73
Which has more liver specificity, ALT or AST?
ALT
AST is for heart
74
In which organ is the activity of CK the greatest?
brain, heart, skeletal muscles
75
What is the main factor that determines how much the level of an enzyme in serum increases?
severity of damage to it's tissues or cells or origin
76
How does the progressive muscular dystrophy affect AST and ALT levels?
cause increase
77
What is the normal value for serum amylase at 37?
95-290 IU/L
78
What is the major CK isoenzyme of normal serums?
MM
79
At what temp should serum CK specimens be stored?
4 degrees C
80
What is the purpose of the PSP test and the p-aminohippurate test?
measures excretory capacity of kidneys
81
To what class of enzymes do amylase and lipase belong?
hydrolase
82
What is the normal value for serum BUN?
8-26 mg/dL
83
What is the old name for AST?
| For CK?
SGOT
| CPK
84
What two isoforms of CK are used for the early detection of an MI?
MM
| MB(1,2)
85
What is the main use of ammonia measurements?
diagnose Reye's syndrome
| hepatic coma
86
What happens to CRcl value in renal disease?
decreases
87
What is the normal range for total serum bilirubin?
0.2-1.0 mg%
88
In the Jendrassik-Grof method, what is the caffeine benzoate solubilizer used for?
makes soluble the water insoluble fractions of bilirubin
89
A list of risk factors for coronary heart disease
```
Smoking
Hypertension
Increased total cholesterol & LDL
Decreased HDL
Diabetes mellitus
Age
Obesity
Physical Inactivity
Family history of premature CHD
Left ventricular hypertrophy
```
90
List of biochemical markers for coronary heart disease
```
Triglycerides
Lp(a)
Homocysteine
Coagulation factors
hs-CRP
```
91
List of the ideal characteristics of a cardiac marker
```
cardiac specific
Rises soon after infarction occurs
Elevated over a sustained period of time
Easy to measure analytically
Broad dynamic range for measurements
Quick turnaround of tests
Diagnostic utility verified by clinical studies
```
92
Which marker has been recognized for the earliest biochemical marker for AMI?
Myoglobin
93
What is the biggest disadvantage of troponin as a cardiac marker?
Stays elevated for 7-10 days
| cant detect new infarction
94
What is the most likely cause of prehepatic bilirubin?
Increased amount of bilirubin being presented to the liver, such as in acute or chronic hemolytic anemias
95
What is the most likely cause of hepatic bilirubin?
most commonly occurs due to primary problem within the liver itself; such as an intrinsic liver disease or defect
96
What is the most likely cause of post hepatic bilirubin?
most commonly occurs due to some type of biliary obstruction (gallstones or tumors)
97
Why are high levels of bilirubin seen in infants?
infant deficiency of enzyme glucuronyl transferase (last to develop because most bili processing done by mother)
98
What precautions need to be taken when processing bilirubin?
Serum or plasma (except in Malloy-Evelyn, use serum)
Fasting specimen preferred
Hemolysis not acceptable
Keep away from light
Stable 2 days at RT, 1 week at 4C, indefinitely at -20C
