1030 Unit 2 Flashcards

1
Q

discuss the relationship of urochrome to normal urine color

A

the more color intensity, the more concentrated

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2
Q

state how the presence of bilirubin may be suspected

A

will produce yellow foam when shaken

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3
Q

state how the presence of uroerythrin may be suspected

A

pink pigment in refrigerated samples

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4
Q

state how the presence of urobilin may be suspected

A

orange-brown color in old sample

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5
Q

state how the presence of biliverdin may be suspected

A

Urine will turn yellow-green when bilirubin is photo-oxidized

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6
Q

discuss the significance of cloudy red urine vs clear red urine

A

red cloudy–> RBC
red clear –> myoglobin or hemoglobin

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7
Q

name two pathological causes of black or brown urine

A

1) melanogen oxidizes to MELANIN which could come malignant melanoma
2)alkaptonuria - HOMOGENTISTIC acid is metabolite of phenylalanine seen in inborn error of metabolism (IEM)

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8
Q

discuss the significance of phenazopyridine in a specimen

A

-will interfere with chemical dipstick
-produce yellow foam
-cling to side of container

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9
Q

list the common terminology to report clarity

A

-clear–>transparent
-hazy–> few particles
-cloudy –> many particles
-turbid–> print cannot be seen through urine
-milky

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10
Q

describe the appearance and discuss the significance of amorphous phosphates and amorphous urates in urine that was freshly voided

A

-in fresh urine, amorphous phosphates and urates are present in normally small amounts

-amorphous phosphates –> react with alkaline pH urine to form white precipitate
-amorphous urates
—->have uroerythrin pigment
—->gives pink brick dust in acidic urine
—->small volumes present in urine is normal
—->adhere to urine or mucous and make diagnosis difficult but it can be separated

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11
Q

what are the three pathological causes of cloudy urine?

A

-RBC
-WBC
-bacteria

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12
Q

what are the five non-pathological causes of cloudy urine?

A

-crystals
-semen, mucous
-fecal contamination
-radiographic contrast media
-talcum powder, vaginal creams

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13
Q

define specific gravity and tell why this measurement can be significant in routine analysis?

A

-density of solution (urine) compared with the density of a similar volume of water (one drop)

-influenced by size and amount of particles. Can detect concentration not seen by the naked eye. heavy concentration can indicate abnormalities

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14
Q

describe principle of refractometer

A

determines the concentration of particles by measuring refract.

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15
Q

describe the principle of reagent strip

A

based on change in pKa of a polyelectrolyte in an alkaline medium

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16
Q

describe the principle of osmolarity

A

expression of the concentration of dissolved particles (solute) in a specific amount of solution (solvent)

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17
Q

Given concentration of glucose and protein in a specimen, calculate the correction needed to compensate for these high molecular weight substances in the refractometer reading of specific gravity

A

-subtract 0.003 for each gram of protein present
-subtract 0.004 for each gram of glucose present

example: specimen containing 1 g/dl protein and 1 g/dl glucose present. Specific gravity of glucose is 1.030

1.030 - 0.003 (protein) = 1.027
1.027 - 0.004 (glucose) = 1.023 corrected specific gravity

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18
Q

Name two nonpathological causes of abnormally high readings of specific gravity using a refractometer

A

1) Radiographic contrast media (IVP)
2) Dextran, other IV plasma expanders

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19
Q

describe the advantages of measuring specific gravity using a reagent strip and osmolarity

A

not affected by high-molecular weight substances

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20
Q

what odor would be present in a specimen with bacterial decomposition (UTI)?

A

foul, ammonia

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21
Q

what odor would be present in a specimen with ketones?

A

fruity, sweet

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22
Q

what odor would be present in a specimen with maple syrup disease?

A

maple syrup

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23
Q

what odor would be present in a specimen that is phenylketonuria ?

A

mousy

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24
Q

what odor would be present in a specimen that is tyrosinemia?

A

rancid

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25
Q

what odor would be present in a specimen that is isovaleric acidemia?

A

sweaty feet

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26
Q

what odor would be present in a specimen that is methionine malabsorption?

A

cabbage

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27
Q

what odor would be present in a specimen that is contaminated?

A

bleach

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28
Q

the concentration of a normal urine specimen can be estimated by what?

A

color

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29
Q

The normal yellow color of urine is produced by?

A

urochrome

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30
Q

the presence of bilirubin in a urine specimen procedures as:

A

yellow foam after being shaken

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31
Q

the urine specimen containing melanin will appear?

A

black

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32
Q

specimen that contain hemoglobin can be visually distinguished from those that contain RBCs because..

A

RBCs produce a cloudy red specimen

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33
Q

a patient with a viscous orange specimen may have been:

A

treated for UTI

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34
Q

The presence of a pink precipitate in a refrigerated specimen is caused by..

A

uroerythrin

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35
Q

microscopic examination of a clear urine that produces a white precipitate after refrigeration will show..

A

amorphous phosphate

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36
Q

the color of urine containing porphyrins will be..

A

port wine

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37
Q

what would be a specific gravity of a pale yellow urine?

A

1.005

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38
Q

a urine specific gravity measured by a refractometer is 1.029 and the temperature of the urine is 14 C. The specific gravity should be reported as

A

1.029

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39
Q

The principle of refractive index is to compare:

A

light velocity in air with light velocity in solutions

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40
Q

a correlation exist between a specific gravity by refractometer of 1.050 and a:

A

radiographic dye infusion

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41
Q

a cloudy urine specimen turns black upon standing and has a specific gravity of 1.012 the major concern about this specimen would be:

A

color

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42
Q

a specimen with a specific gravity of 1.035 would be considered:

A

hypersthenuric

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43
Q

a specimen will a specific gravity of 1.001 would be considered:

A

not urine

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44
Q

a strong odor of ammonia in urine specimen would indicate:

A

an old specimen

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45
Q

the microscopic examination of a clear red urine in reported as many WBCs and epithelial cells. What does this suggest?

A

possible mix up of specimen and sediment

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46
Q

which of the following would contribute the most to a urine osmolarity?
A. one osmole of glucose
B. one osmole of urea
C. one osmole of sodium chloride
D. all contribute equally

A

C. one osmole of sodium chloride

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47
Q

The boiling point is _____ by solute

A

raised

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48
Q

the vapor pressure is ______ by solute

A

lowered

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49
Q

the osmotic pressure is _____ by solute

A

raised

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50
Q

what does an osmole contain?

A

one gram molecular weight of solute dissolved in 1 kg of solvent

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51
Q

the unit of osmolarity measured in the clinical laboratory is the …

A

osmole

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52
Q

in the reagent strip for specific gravity reaction..

A

release hydrogen ions in response to ion concentration

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53
Q

what will react in the reagent strip specific gravity?

A

chloride

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54
Q

what are the steps for performing reagent strip testing?

A

1) Dip strip in to well-mixed urine at room temperature
2) Remove excess urine by touching edge to the container as the strip is removed
3) Blot the edge of strip on absorbent pad
4) Wait for specific time to read (time is critical)
5) Read using good light, report results

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55
Q

what are four causes of premature deterioration of reagent of strips and describe how to avoid to form?

A

-moisture
-volatile chemicals
-heat
-light
- keep lid on as much as possible

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56
Q

list 5 quality control procedures routinely performed with reagent strip testing

A

1) test open bottle of reagent strips with known positive and negative controls per facility protocol
2) Resolve control results that are out of range by further testing
3) Test reagents used in confirmatory tests with positive and negative control
4) Perform positive and negative controls on new reagents and newly opened bottles of reagent strips
5) Record all control results and reagent lots number

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57
Q

list the reasons for measuring urinary pH, and discuss their clinical applications

A
  • helps determining acid-base disorders of metabolic or respiratory origin
    -help in management in urinary conditions that require the urine to maintain a specific pH
    -the inorganic chemicals dissolve in the urine and can form crystals which can become renal calculi
    -an acidic urine can aid in treating UTI
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58
Q

discuss principle of pH testing by reagent strip

A

-strip read in increments 0.5 or 1 ranging between 5 to 8.5 or 9
-both manufacturers use a double indicator
—>methyl red -> red to yellow (pH 4 to 6)
—>bromothymol blue -> yellow to blue (pH 6 to 9)

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59
Q

Describe and discuss prerenal proteinuria

A

-proteins that come from the plasma before it gets to kidneys
-condition may be short term
-if proteins are high, will reabsorb and overflow into urine
-increase of protein (Bence Jones protein) in plasma is multiple myeloma
-increase in antibody light chains
-examples: hemoglobin,. myoglobin, acute phase reactants due to infection and inflammation
-to diagnose: need to have serum protein electrophoresis and immunoelectrophoresis

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60
Q

Describe and discuss tubular dysfunction in Renal proteinuria

A

-tubular reabsorption problems are caused by increase of albumin
-other low molecular weight particles that are normally reabsorbed end up being excreted through urine
- Caused by:
—->exposure to toxic substances
—->heavy metal
—->severe viral infections
—->Fanconi syndrome
-tubular damage results in low levels of proteins excreted

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61
Q

Describe and discuss glomerular dysfunction of Renal proteinuria

A

-glomerular membrane is damaged/not filtering properly
—->allow serum proteins through
—->leads to excretion of RBC and WBC
—->Amyloid material = toxic substances, immune complexes (IgA, IgG, antibodies)
—-> increased pressure caused increased amount of albumin to enter filtrate
- glomerular damage = 4 g/dl daily of protein excretion
-may be reversible in hypertension, strenuous exercise, dehydration, and pregnancy (preeclampsia)

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62
Q

Discuss and describe postural proteinuria

A
  • seen after periods of staying in a vertical position and then disappears after being in a horizontal position
    -Caused by: increased pressure on the renal vein when in vertical position
    -patients instructed to collect orthostatic urine
    -protein can be added to urine after kidney from any of the structures of the lower urinary tract (urethra, bladder, ureters, prostate, vagina )
    -proteins can also be found with/in:
    —-> bacterial/fungal infections
    —->inflammation
    —->blood from injury or menstruations
    —->prostatic fluid
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63
Q

What are the steps of collecting an orthostatic urine and explain

A

1) empty bladder before bed
2) collect 1st sample after being in horizontal position
3) collect 2nd sample after being vertical position
-results : 1st–>negative; 2nd –> positive

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64
Q

explain “protein error of indicators”

A

-color change is in response to pH
- certain indicators change in presence of protein even in pH is constant
-Reason: because albumin accepts hydrogen ions
-sensitive to albumin because there are more amino groups to accept H+

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65
Q

What are some sources of interference that can occur during “error protein indicator” method?

A

-Major reason: highly alkaline urine overriding the acid system. Rise in pH w/o protein presence
-leaving reagent pad in urine too long
-false positive
—-> pigmented urine
—->container having ammonium compound detergents, antiseptics
—-> blood may result in high proteins

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66
Q

Discus microalbuminuria

A

-abnormally increased excretion rate of albumin in the urine in the range of 30-299 mg/g creatinine
-semiquantitative strips for patient at risk of renal failure. 1st morning specimen recommended
-tests that measure of albumin and/or creatinine = micral test and immunodip

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67
Q

Describe the Micral test

A

-gold labeled
-antihuman albumin antibody-enzyme conjugate
-albumin binds to antibody (Alb-AB)
- color reaction is white to red
-results range from 1-10 mg/dL

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68
Q

Describe immunodip

A

-immunochromographic technique
-special designed container is placed in the urine for 3 minutes
-it can measure bound and unbound, they migrate up the strip, color intensity of bans is compared to a chart

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69
Q

explain why glucose that is normally reabsorbed in the proximal convoluted tubule may appear in the urine and state the renal threshold levels for glucose?

A

-if glucose exceeds renal threshold which is 160-180 mg/dL, it will spill over into urine

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70
Q

What are possible interferences in the glucose oxidase method of reagent strip testing

A

-False positive –> contaminated w/ peroxidase or strong oxidizing detergents
-False negative
—->strong reducing agents = Ascorbic acid (vitamin C)
—-> high levels of ketones
—-> high specific gravity and low temperature
—-> unpreserved urine increase bacteria cause a decrease in glucose

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71
Q

Describe principle of glucose oxidase method of reagent strip testing for glucose

A

-glucose oxidase –> specificity looks for glucose (no other sugars)
-2 step process v glucose oxidase
—-1) glucose + O2 —-> gluconic + H2O2
—-2) H2O2 + chromogen —-> oxidized
^Peroxidase
-color is proportional to concentration

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72
Q

Describe copper reduction method for the detection of urinary-reducing substances and discuss current use of this procedure

A

-cupric sulfide reduce to cuprous oxide resulting in a color change
v Heat
CuSO4 + reducing substance ——> Cu2O + oxidized substance = color
-color change from blue -> green -> yellow -> orange/red -> brown

-used for detecting reducing sugars in infants.

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73
Q

What are the 3 ketone bodies that appear in urine

A

1) Beta-hydroxybutyrate (78%)
2) Acetoacetic acid (20%)
3) Acetone (2%)

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74
Q

What are 3 causes of ketonuria?

A

1) diabetes mellitus
2) Decrease of carbohydrate (or loss)
3) inadequate amounts of carbs associated with starvation and malabsorption

75
Q

Discuss the principle of the sodium nitroprusside reaction to detect ketones

A

-acetoacetic acid in alkaline medium reacts with sodium nitroprusside to produce a purple color

76
Q

what are sensitivities or interferences that can occur in sodium nitroprusside reaction to detect ketones?

A
  • Beta-hydroxybutyrate is not picked up by the strip
  • Prescription drugs
    —-> large amounts of Levadopa
    —->sulfhydryl = capitopril and MESNA
    -false positive –> improper reading
    -false negative –> breakdown of acetoacetic acid by bacteria
77
Q

Discuss the hematuria with regard to the appearance of urine and serum, as well as clinical difference

A

-intact RBC
-Red-cloudy specimen
-renal and genitourinary
-from trauma or damage
- most common —> renal calculi, glomerular disease, tumor, pyelonephritis, exposure to toxic chemicals, anti coagulation therapy
-symptoms–> severe back and abdominal pain
-nonpathogenic –> strenuous exercise or menstruation

78
Q

Discuss the hemoglobin with regard to the appearance of urine and serum, as well, as well as clinical difference

A

-destroyed RBC leaving the hemoglobin
-red clear specimen
-from lysis of RBCs, especially alkaline urine
-from intravascular hemolysis (hemoglobin only)
-lysis may see RBC and hemoglobin
-when haptoglobin is all occupied with hemoglobin will the hgb spill over
- increased free hgb causes increase in haptoglobin
—->hemolytic anemias
—->transfusion reaction
—->severe burns
—-> infection/malaria/spider bite
-Denatured ferritin = hemosiderin yellow brown granules

79
Q

Discuss the myoglobin with regard to the appearance of urine and serum, as well, as well as clinical difference

A

-red/brown clear specimen
-heme protein from muscle
- seen in patients with muscle destruction —> trauma, crush syndrome, prolonged coma, convulsions, muscle-wasting disease, alcoholism, heroin abuse, extensive exertion, dng related
-myoglobin is toxic to renal tubule and may cause renal failure

80
Q

describe the chemical principle of the reagent strip method for blood testing

A

-pseudo peroxidase activity of heme protein in hemoglobin and myoglobin and chromogen tetramethylbenzidine produces an oxidized chromogen
v peroxidase
H2O2 + chromogen——–>oxidized chromogen + H2O

81
Q

what are some interference of the reagent strip method for blood testing?

A

-false positive
—->menstruations,
—->strong oxidizers
—->vegetable peroxidase
—-> bacteria enzymes
—-> sediment should be observed
-false negative
—->Ascorbic acid > 25 mg/dL
—->high specific gravity due to creanated RBC that have not lysed
—-> formalin
—->captopril (high BP meds)
—->high concentration of nitrite (bacteria)
—->unmixed specimen

82
Q

what are the steps in degradation of hemoglobin to bilirubin, urobilinogen, and urobilin?

A

1) Ruined RBC from spleen and liver, hemoglobin is liberated
2)hemoglobin reduced to: iron, protein, and protoporphyrin
3)iron and protein are reused by body. Protoporphyrin in converted into bilirubin by reticuloendothelial system cells
4) Bilirubin is released into blood circulation binds with albumin
5) It is then transported to liver. In this condition, bilirubin is water insoluble and cannot excrete through urine
6) Bilirubin are conjugated with glucuronic acid in liver by glucuronyl transferase to produce bilirubin digluconide (water soluble bilirubin). This is called conjugated bilirubin.
7) This conjugated bilirubin from liver enter bile duct and then to intestine
8) Bacteria present in intestine forms urobilinogen by reducing bilirubin
9) urobilinogen is oxidized and eliminated in feces as urobilin and stercobilinogen

83
Q

Describe relationship of urinary bilirubin to each of the following diagnosis: bile duct obstruction, liver disease, and hemolytic disorders

A

-conjugated bilirubin only occurs in urine when degradation phase is disturbed due to bile duct obstruction (post hepatic jaundice)
—->cancer or gall stones or liver integrity damage permits conjugated bilirubin to move in circulation
—->absence or presence of urinary bilirubin helps to identify clinical jaundice
—->liver is damaged by hepatitis or cirrhosis condition ‘
—->urine bilirubin shows positive results to bile duct obstruction
-provides early indication of liver disease
-may show +ve and -ve results for liver damage
-negative results is seen in urine bilirubin for hemolytic disease

84
Q

Describe relationship of urinary urobilinogen to each of the following diagnosis: bile duct obstruction, liver disease, and hemolytic disorders

A

-reduced form of bilirubin
-provides results associated with bile duct obstruction
-liver damage is indicated through urinary urobilinogen. Shows positive results for for liver damage
-hemolytic disorders are associated with urobilinogen in urine and is positive

85
Q

Discuss principle of the reagent strip tests for urinary bilirubin

A

-multistix = Ehrlich reaction
-p-dimethylaminobenaldehyde producing a reaction from light to dark pink
v Heat
urobilinogen + reagent ———-> red color

86
Q

what are some sources of error when performing reagent strip testing for urinary bilirubin

A

-Ehrlich is subject to false positive
—->porphobilinogen
—->indicant
—->p-amino salicylic acid
—->sulfonate
—->methyldopa
—->procaine
—->chlorpromazine compounds
—->highly pigmented urine
—->bile salts from after meal
-false negative
—->exposure to light
—->high concentrate of nitrite

-

87
Q

what are the two reasons for increased urine urobilinogen ?

A

1) liver disease
2) hemolytic disorders

88
Q

what is the reason for decreased urine urobilinogen?

A

antibacterial medication

89
Q

Discuss the principle of the nitrite reagent strip test for bacteriuria

A

-test for the ability for gram-negative bacteria to reduce nitrate to nitrite
-Griess reaction —> nitrite at acid pH reacts with aromatic amine to form diazonium compound that reacts with tetrahydrobenzoquinoline to produce a pink azo dye
v Acid
para-arsanilic aicd + NO2 ——–> diazomium tetrahydrobenzoquinolin——-> pink azo dye or sulfanilamide ^ Acid

90
Q

what are possible causes of a false-negative in the reagent strip test for nitrite

A

-Bacteria that lacks enzymes to reduce nitrate to nitrite
-Bacteria must stay in contact long enough to reduce. Timing is critical
-dietary nitrate need to be present from green vegetables
-Too many bacteria causing the nitrate to reduce to nitrite then onto nitrogen
-presence of antibodies
-Ascorbic acid
-high specific gravity

91
Q

state principle of the reagent strip test for leukocytes

A

-reaction is based on the action of leukocytes to catalyze the hydrolysis of an acid combined with diazonium salt to produce a purple azo dye
v Leuk. Esterase
indoxylcarbonic acid ester ——-> indoxyl + acid indoxyl +diazonium salt ———>purple azo dye
^ Acid

92
Q

Discuss advantages of the reagent strip test for leukocytes

A

-chemical test provide standardized results for detecting leukocytes
-can detect leukocytes AND lysed leukocytes (which can not be seen under a microscope

93
Q

Discuss sources of error of the reagent strip test for leukocytes

A

-False positive
—->strong oxidizers (detergents)
—-> formalin
—-> highly pigmented urine
—->nitrofurantoin (antibiotic)
-False negative
—->high concentration of proteins, glucose, oxalic acid, ascorbic acid
—->inaccurate timing: must be 2 minutes
—->presence of antibiotics (Gentamicin, Cephalosporins, Tetracyclines)

94
Q

Explain the principle of chemical test for specific gravity

A

change in Dissociation constant pKa

95
Q

compare reagent strip testing for specific gravity with osmolarity and refractometer testing

A

-strip = not as accurate
-osmolarity = specific gravity depends on number and density of particles in a solution but less convenient
-refractometer = best and mostly used testing

96
Q

Define bacteriuria

A

bacteria in urine

97
Q

define bilirubin

A

bright yellow pigment produced in the degradation of heme

98
Q

define clarity/character

A

transparency of urine, range from clear to turbid

99
Q

define glycosuria

A

glucose in urine

100
Q

define hematuria

A

blood in urine

101
Q

define hemoglobinuria

A

hemoglobin in the urine

102
Q

define hypersthenuria

A

condition where the osmolality of urine is increased

103
Q

define isothenuria

A

urine with an osmolarity the same as that of the plasma

104
Q

define jaundice

A

yellow appearance of skin, mucous membranes and eye sclera due to increased amounts of bilirubin in the blood

105
Q

define ketonuria

A

ketones in the urine

106
Q

define myoglobinuria

A

myoglobin in the urine

107
Q

define orthostatic proteinuria

A

increased protein in urine only when an individual is in an upright position.

108
Q

define post-renal proteinuria

A

occurs with inflammation of urinary tract

109
Q

define pre-renal proteinuria

A

abnormal plasma content in plasma before kidney

110
Q

define protein error of indicators

A

indicators change color in the presence of protein of a constant pH

111
Q

define proteinuria

A

protein in urine

112
Q

define refractometer

A

instrument that measures substances refractive index

113
Q

define specific gravity

A

density of a solution compared with that of a similar volume or distilled water, influenced by both the number and size of particles present

114
Q

define urometer

A

urine collection bag or closed urine bag used mainly for the patients with urinary catheter for the collection of urine

115
Q

what will happen if the excess urine is left on reagent strip after pulling it out of specimen?

A

cause runover between reagent pads

116
Q

Failure to mix a specimen before inserting the reagent strip will primarily affect…

A

blood reading and leukocyte reading

117
Q

Testing a refrigerated specimen that has not warmed to room temperature will adversely affect what?

A

enzymatic reactions

118
Q

what is the reagent strip reaction that requires the longest reaction time?

A

leukocyte esterase

119
Q

what are some quality controls of the reagent strip is performed?

A

-using positive and negative controls
-when results are questionable
-per laboratory policy

120
Q

How do you protect the integrity of the reagent stripes?

A

1) storing in opaque bottle
2) storing at room temperature
3) resealing the bottle after removing a strip

121
Q

what is the principle of the reagent strip for pH?

A

double indicator reaction

122
Q

what should happen if the urine specimen has a pH of 9.0?

A

recollect specimen

123
Q

what are the primary considerations associated with pH?

A

-identifying urinary crystals
-determining specimen acceptibility

124
Q

what is the source of microalbuminuria?

A

renal

125
Q

what is the source of acute-phase reactants?

A

pre-renal

126
Q

what is the source of preeclampsia?

A

renal

127
Q

what is the source of vaginal inflammation?

A

post-renal

128
Q

what is the source of multiple myeloma?

A

pre-renal

129
Q

what is the source of orthostatic proteinuria?

A

renal

130
Q

what is the source of prostatis?

A

post-renal

131
Q

what is the principle protein error of indicators?

A

albumin accepts H+ ions from the indicator

132
Q

A patient with a 2+ protein reading in the afternoon is asked to submit a first morning specimen. The second specimen has a negative protein reading. what is this patient?

A

positive for orthostatic proteinuria

133
Q

testing for microalbuminuria is valuable for early detection of kidney disease and monitoring patients with what?

A

-hypertension
-diabetes mellitus
-cardiovascular disease risk

134
Q

what is the primary chemical on the reagent strip in the Mcral-test for microalbuminuria?

A

antihuman albumin antibody

135
Q

what are characteristics for the immunodip for microalbumin?

A

-blue latex particles are coated with antihuman albumin antibody
-bound antibody migrates farther than unbound antibody
-utilizes an immunochromographic principle

136
Q

what is the principle of the protein-high pad on the Multistix pro strip?

A

protein error of indicators

137
Q

what is the principle of the protein-low reagent pad on the multistix pro?

A

binding of albumin to sulphonpnhtalein dye

138
Q

what is the principle of the creatinine reagent pad on microalbumin reagent strip?

A

pseudoperoxidase reaction

139
Q

what is the purpose of performing an albumin: creatinine ratio?

A

estimate glomerular filtration rate

140
Q

A patient with a normal blood glucose and a positive urine glucose should be further checked for what?

A

diabetes mellitus

141
Q

what is the principle of the reagent strip for glucose?

A

double sequential enzyme reaction

142
Q

what is the primary reason for performing clinitest?

A

check for newborn galactosuria

143
Q

what is the most significant reagent strip test that is associated with a positive ketone results?

A

glucose

144
Q

what is the primary reagent in the reagent strip test for ketones?

A

sodium nitroprusside

145
Q

what can cause ketonuria?

A

-diabetes acidosis
-starvation
-vomiting

146
Q

what is checked for when patient is experiencing severe back and abdominal pain?

A

hematuria

147
Q

what is associated with transfusion reactions?

A

hemoglobinuria

148
Q

what has clear red urine and place yellow plasma?

A

myoglobinuria

149
Q

what has clear red urine and red plasma

A

hemoglobinuria

150
Q

what is associated with rhabdomyolysis?

A

myoglobinuria

151
Q

what produces hemosiderin granules in urinary sediment?

A

hemoglobinuria

152
Q

what is associated with acute renal failure?

A

myoglobinuria

153
Q

what is the principle of the reagent strip test for blood based on?

A

peroxidase activity of heme

154
Q

what does a speckled pattern on the blood pad of a reagent strip indicate?

A

hematuria

155
Q

In correct order, what are the products of hemoglobin degradation of metabolism?

A

1)conjugated bilirubin
2)unconjugated bilirubin
3)urobilinogen and stercobilinogen
4)urobilin

156
Q

what is the principle of the reagent strip test for bilirubin?

A

diazo reaction

157
Q

what does an elevated urine bilirubin with a normal urobilinogen indicate?

A

biliary obstruction

158
Q

what is the primary cause of a false-negative bilirubin reaction?

A

specimen exposure to light

159
Q

what is the purpose of the special mat supplied with the ictotest tablets?

A

bilirubin stays on the surface of the mat

160
Q

what is the reagent of the Multistix reaction for urobilinogen?

A

p-dimethylaminobenzaldehyde

161
Q

what are primary problems with urobilinogen tests using Ehrlich reagent?

A

-positive reactions w/ porphobilinogen
-lack of specificity
-positive reactions with Ehrlich reactive substances

162
Q

The reagent strip test for nitrite uses what?

A

Griess reaction

163
Q

A positive nitrite test and a negative leukocyte esterase test indicates what?

A

specimen older than 2 hours

164
Q

what can be detected by the leukocyte esterase reaction?

A

neutrophils, basophils, and eosinophils

165
Q

when screening for urinary infection, what are two things that should be screened for?

A

1) leukocytes esterase
2) nitrite

166
Q

The principle of the leukocyte esterase reagent strip test uses a what?

A

Diazo reaction

167
Q

The principle of reagent strip for specific gravity uses the dissociation constant of what?

A

polyelectrolyte

168
Q

what color would be produced on a reagent strip with specific gravity of 1.005?

A

blue

169
Q

what affects the readings of specific gravity on reagent strip?

A

alkaline urine

170
Q

what are possible causes for the urine color to be orange-yellow?

A

-pyridium
-azo
-phenindione

171
Q

what are possible causes of yellow-green urine color?

A

bilirubin oxidized to biliverdin

172
Q

what are possible causes of green urine color?

A

-pseudomonas infection
-asparagus

173
Q

what are possible causes of blue urinecolor?

A

-drugs
-indican

174
Q

what are possible causes of pink/red urine color?

A

-RBC
-hemoglobin
-myoglobin
-beets
-drugs

175
Q

what are possible cause of red-brown urine color?

A

RBC oxidizes to methemoglobin, myoglobin

176
Q

what is one of the kidneys most important functions?

A

ability to concentrate the glomerular filtrate by reabsorption of chemicals and water

177
Q

what would be considered isosthenuric?

A

specific gravity of 1.010

178
Q

what would be considered hypersthenuric?

A

specific gravity higher than 1.010

179
Q

what would be considered hyposthenuric?

A

specific gravity lower than 1.010

180
Q

what is considered the “normal range” for specific gravity in urine

A

-1.002 - 1.035
-most common: 1.015 - 1.030

181
Q

what two organs regulate the acid-base content in the body?

A

lungs and kidneys

182
Q

what is considered normal range for pH?

A

4.5 - 8.0
more acidic in the morning
more alkaline after meal

183
Q

what is uromodulin?

A

-Tamm-Horsfall protein –> glycoprotein produced in the ascending loop of Henle
-proteins by epithelial cells
-from prostatic, vaginal or seminal secretions