Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Clinical Chemistry > NPNs > Flashcards

NPNs Flashcards

1
Q

The concentration of nitrogen-containing compounds
in this protein-free filtrate was quantified spectrophotometrically by converting
nitrogen to ammonia and subsequent reaction with ________ reagent to produce a yellow color

A

Nessler’s reagent (K2[HgI4)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Most abundant NPN to least

A 
Urea
Amino acids
Creatinine
Creatine
Ammonia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

the major excretory product of protein metabolism.

A

Urea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Small quantities of urea

(<10% of the total) are excreted through the:

A

GI tract & skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Reference method for Urea

A

isotope dilution mass spectrometry (IDMS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Analytic methods (Urea): Conversion of unionized urea to NH4 & CO2-3 results in increased conductivity

A

Conductometric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Analytic methods (Urea): Enzymatic reaction of NH4 2-oxoglutarate & NADH to form glutamate & NAD+

A

GLDH-couple enzymatic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Normal value of Urea Nitrogen (plasma/serum)

A

6-20mg/dl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Normal value of Urea Nitrogen (urine)

A

12-20g/d

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

An elevated concentration of urea in the blood is called

A

azotemia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Very high

plasma urea concentration accompanied by renal failure is called

A

uremia or the

uremic syndrome.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

is a result of reduced renal blood flow. Less blood is

delivered to the kidney; consequently, less urea is filtered.

A

Prerenal azotemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Decreased renal function causes an increase in plasma urea concentration as
a result of compromised urea excretion.

A

renal azotemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

can be due to
obstruction of urine flow anywhere in the urinary tract by renal calculi, tumors
of the bladder or prostate, or severe infection.

A

Postrenal azotemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The major causes of decreased plasma urea concentration include

A

low

protein intake and severe liver disease. Pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Urea: Increased
Urea N/C ratio: High
Crea: Normal

A

Prerenal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Urea: Increased
Urea N/C ratio: High
Crea: Increased

A

Postrenal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

product of catabolism of the purine nucleic acids.

A

Uric acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Renal excretion

accounts for about __% of uric acid elimination;

A

70

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Nearly all of the uric acid in plasma is present as

A

monosodium urate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Most other mammals have the ability to

catabolize purines to _______, a more water-soluble end product.

A

allantoin

22
Q

based on the
oxidation of uric acid in a protein-free filtrate, with subsequent reduction of phosphotungstic acid in alkaline solution to tungsten blue. The method lacks
specificity.

A

Caraway method

23
Q

Reference method for URIC ACID

A

IDMS

24
Q

Drugs such as

__________ have been shown to increase values for uric acid.

A

salicylates and thiazides

25
Q

may falsely

decrease results obtained by peroxidase methods.

A

High bilirubin

26
Q

should not be used

for specimens that will be tested by a uricase method.

A

EDTA/Fluoride additives

27
Q

a disease found
primarily in men and is usually first diagnosed between 30 and 50 years of age.
Affected individuals have pain and inflammation of the joints caused by
precipitation of sodium urates.

A

Gout

28
Q

result of overproduction of uric acid, although hyperuricemia may be
exacerbated by a purine-rich diet, drugs, and alcohol.

A

hyperuricemia

29
Q

which inhibits xanthine oxidase (EC

1.1.3.22), an enzyme in the uric acid synthesis pathway, is used for treatment.

A

Allopurinol

30
Q

TRUE/FALSE: Patients with hemolytic or megaloblastic anemia may exhibit elevated uric
acid concentration.

A

TRUE

31
Q

X-linked genetic disorder (seen only in males) caused by the complete
deficiency of hypoxanthine–guanine phosphoribosyltransferase (EC 2.4.2.8), an
important enzyme in the biosynthesis of purines.

A

Lesch-Nyhan syndrome

32
Q

Mutations in the first enzyme
in the purine synthesis pathway, _______ (EC
2.7.6.1), also cause elevated uric acid concentration.

A

phosphoribosylpyrophosphate synthetase

33
Q

result of decreased uric acid excretion is a common
feature of toxemia of pregnancy (preeclampsia) and lactic acidosis presumably
as a result of competition for binding sites in the renal tubules.

A

Hyperuricemia

34
Q

Liver disease
Fanconi syndrome
Chemotherapy with azathiprine/6-mercaptopurine
Overtreatment with allopurinol

A

Hypouricemia

35
Q

Plasma

creatinine is _____ related to glomerular filtration rate (GFR)

A

inversely

36
Q

Creatine is synthesized primarily in the liver from ____ (amino acids)

A

arginine, glycine, and

methionine.

37
Q

used to determine the sufficiency of
kidney function, to determine the severity of kidney damage, and to monitor the
progression of kidney disease.

A

Measurement of creatinine concentration

38
Q

a measure of the amount of creatinine

eliminated from the blood by the kidneys, and GFR are used to gauge renal function

A

Creatinine clearance (CrCl)

39
Q

Modification

of Diet in Renal Disease (MDRD) equation variables:

A

serum creatinine concentration, age, gender (sex), and

ethnicity

40
Q

has been developed to calculate

eGFR in the pediatric population.

A

modified Schwartz equation

41
Q

In this reaction, creatinine reacts with picric

acid in alkaline solution to form a red-orange chromogen.

A

Jaffe

reaction

42
Q

used routinely despite these problems because it is inexpensive, rapid, and easy
to perform.

A

kinetic Jaffe method

43
Q

Reference method for Creatinine

A

IDMS

44
Q

may increase creatinine
concentration measured by the Jaffe reaction, especially at temperatures above
30°C.

A

Ascorbate, glucose, α-keto acids, and uric acid

45
Q

May falsely elevate Crea when Jaffe reaction is used

A

cephalosporin antibiotics

46
Q

causes a positive bias in some enzymatic

methods.

A

Lidocaine

47
Q

known to affect both enzymatic

and Jaffe methods.

A

Dopamine

48
Q

Plasma creatinine is a relatively insensitive marker and may not be measurably
increased until renal function has deteriorated more than ___%

A

50

49
Q

produced in the deamination of amino acids during protein
metabolism.
5
It is removed from the circulation and converted to urea in the
liver.

A

Ammonia

50
Q

is the most common cause of disturbed ammonia metabolism.

A

Severe liver disease

51
Q

occurring most commonly in children, is a serious disease
that can be fatal. Frequently, the disease is preceded by a viral infection and the
administration of aspirin.

A

Reye’s syndrome

52
Q

associated with inherited deficiency of urea cycle

enzymes.

A

Hyperammonemia

Clinical Chemistry (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions