NPNs: Urea

Question 1

catabolites of protein and nucleic acid metabolism

Answer 1

Nonprotein Nitrogen

Question 2

NPNs are (5)

Answer 2

Urea
Ammonia
Creatinine
Creatine
Uric Acid

Question 3

Major waste product dietary protein and amino acid catabolism

Answer 3

Urea

Question 4

Synthesized in the liver from Co2 and Ammonia from DEAMINATION OF AMINO ACID and excreted by kidney

Answer 4

Urea

Question 5

First metabolite to increase in kidney disease

Answer 5

Urea

Question 6

Good indicator of
1. Nitrogen status
2. State of hydration

Answer 6

Urea

Question 7

Amount of dietary protein
Kidney’s ability excrete urea
Protein Metabolism
Degree of hydration

Answer 7

Affecting Factors of Blood Urea Level

Question 8

Condition by which there is an INCREASED IN BLOOD UREA

Answer 8

Uremia

Question 9

Condition by which ALL NPNS INCREASED

Answer 9

Azoremia

Question 10

Concentration is expressed only as the ___ content of urea

Answer 10

NITROGEN
BUN (Blood Urea Nitrogen)

Question 11

____ x BUN = Urea

Answer 11

2.14 x BUN = Urea

Question 12

____ x 0.467 = BUN

Answer 12

Urea x 0.467 = BUN

Question 13

Reference Value for Urea

Answer 13

5-38 mg/dL (Serum/plasma)

Question 14

Laboratory Methods for Urea:

Specimen Requirement

Answer 14

Plasma or Serum (Fasting is preferred; Nonfasting may be used)

Question 15

Laboratory Methods for Urea:

Tubes to be avoided in BUN (Inactivates Urease)

Answer 15

Citrate
Sodium Fluoride

Question 16

Laboratory Methods for Urea:

If delay testing, spx must be _____ to avoid bacteria utilization to urea

Answer 16

Refrigeration

Question 17

Laboratory Methods for Urea:

Chemical Method (Direct) for Urea ; Nonspecific, Simple

Answer 17

Fearson Reaction / Diacetyl Monoximide Method

Question 18

Laboratory Methods for Urea:

Fearson Reaction / Diacetyl Monoximide Method = Result

Answer 18

YELLOW diazine derivatives

Question 19

Laboratory Methods for Urea:

Enzymatic Method (Indirect) (2)

Answer 19

1. Hydrolysis of Urea by Urease
2. Coupled Urease - GLD enzyme Reaction (UV enzymatic)

Question 20

Laboratory Methods for Urea:

Hydrolysis of Urea by Urease;

Ammonium + Nessler;s Reaction (HgI or KI and gum ghatti) =

Answer 20

Yellow

Question 21

Hydrolysis of Urea by Urease;

Ammonium + Berthelot’s reaction (Alk. Hypochlorite, Na nitroprusside) =

Answer 21

Blue

Question 22

Laboratory Methods for Urea:

Specific, more expensive
Uses GLUTAMATE DEHYDROGENASE
Measures disappearance of NADH at 340 nm

Answer 22

Coupled Urease - GLD enzyme

Question 23

Laboratory Methods for Urea:

Conversion of ammonium to Urea causes increased in conductivity

Answer 23

Conductimetric

Question 24

Laboratory Methods for Urea:

Reference Method

Answer 24

IDMS
Isotope Dilution Mass Spectrometry

Question 25

Azotemia:

Reduced Blood Flow
Poor Kidney Perfusion

Answer 25

Pre-renal

Question 26

Azotemia:

Damage to filtrating structure (tubules, glomerulus)

Answer 26

Renal

Question 27

Azotemia:

Urinary Tract Obstuction

Answer 27

Post-Renal