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Analysis of Urine and Other Body Fluids (Laboratory) > Chemical Examination of Urine (M) > Flashcards

Chemical Examination of Urine (M) Flashcards

1
Q

What are the purposes of reagent strips?

A

1) For routine chemical examination

2) To provide a simple, rapid means for performing medically significant chemical analysis of urine

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2
Q

What are included in the chemical analysis of urine?

A

1) pH
2) Glucose
3) Blood
4) Urobilinogen
5) Leukocytes
6) Protein
7) Ketones
8) Bilirubin
9) Nitrite
10) Specific gravity

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3
Q

What are the characteristics of reagent strips?

A

1) It consists of chemical-impregnated absorbent pads attached to a plastic strip
2) A color producing chemical rxn takes place when the absorbent pad comes in contact with the urine

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4
Q

How are the rxns via the use of reagent strips being interpreted?

A

The rxns are interpreted by comparing the color produced on the pad, within the required time frame, w/ the chart supplied by the manufacturer

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5
Q

What are the 2 major types of reagent strips manufacturer?

A

1) Multistix (Siemens Healthcare Diagnostics, Deerfield, IN)

2) Chemstrip (Roche Diagnostics, Indianapolis, IN)

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6
Q

What are the manner of reporting via the use of reagent strips?

A

1) Trace
2) 1+ (+)
3) 2+ (++)
4) 3+ (+++)
5) 4+

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7
Q

True or False

Automated rgnt strip readers also provide SI units?

A

True

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8
Q

What is the process (or steps) of rgnt strip technique?

A

1) Dip the rgnt strip briefly into a well-mixed uncentrifuged urine sx at room temp
2) Remove excess urine by touching the edge of the strip to the container as the strip is withdrawn
3) Blot the edge of the strip horizontally on an absorbent medium
4) Wait the specified length of time for rxns to take place
5) Compare the colored rxns against the manufacturer’s chart using a good light source

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9
Q

What are the errors that can occur caused by the utilization of improper technique (via the use of rgnt strips)?

A

1) Formed elements such as RBCs and WBCs sink to the bottom of the sx and will be undetected in an unmixed sx
2) Allowing the strip to remain in the urine for an extended period may cause leaching of rgnts from the pads
3) Excess urine remaining on the strip after its removal from the sx can produce a run-over bet chemicals on adjacent pads, producing distortion of the colors
4) For best semiquantitative results, the manufacturer’s stated time should be followed
5) Always use a good light source

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10
Q

How to avoid run-over of urine in diff chemical rgnt pads in rgnt strips?

A

Blot the edge of the strip on absorbent paper horizontally

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11
Q

What is the purpose of good light source in interpretation of results using rgnt strips?

A

It is essential for accurate interpretation of color rxns

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12
Q

True or False

The timing for rxns to take place does not vary bet tests and manufacturers

A

False, because the timing for rxns to take place varies bet tests and manufacturers

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13
Q

What is the timing for rxns to take place via the use of rgnt strips?

A

For pH: immediate rxn

For LE: 120secs

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14
Q

When precise timing can’t be achieved, what does the manufacturers recommend for them to be read?

A

Bet 60 - 120secs

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15
Q

The rxn for LE should be read at what time?

A

It should be read at 120secs

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16
Q

What must be done when the rgnt strip rxns are being read?

A

The strip must be held close to the color chart w/out actually being placed on the chart

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17
Q

Does automated rgnt strip instruments standardize the color interpretation and timing of the rxn?

A

Yes

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18
Q

Are the rgnt strips and color charts from diff manufacturers interchangeable?

A

No, because the rgnt strips and color charts from diff manufacturers are not interchangeable

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19
Q

What should be done to refrigerated sxs?

A

These sxs must be allowed to return to room temp prior to rgnt strip testing

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20
Q

Why are refrigerated sxs must be allowed to room temp prior to rgnt strip testing?

A

Because the enzymatic rxns on the strips are temp dependent

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21
Q

What are the considerations for handling and storage of rgnt strips?

A

1) Rgnt strips must be protected from deterioration caused by moisture, volatile chemicals, heat, and light
2) These should be packaged in opaque containers
3) These should be removed just prior to testing, and the bottle is tightly released immediately
4) These must be stored at room temp below 30 DC
5) These must not be used if these are past the expiration date
6) Don’t touch the chemical pads when removing the strips

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22
Q

What should be done to rgnt strips (as a part of handling of these strips)?

A

A visual inspection of the strip should be done each time a strip is used to detect deterioration

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23
Q

When and how is QC of rgnt strips done?

A

Rgnt strips should be checked w/ both (+) and (-) controls once every 24hrs

QC is also performed when a new bottle of rgnt strips is opened

When there are questionable results obtained

When there is concern about the integrity of the strips

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24
Q

What must be done to all QC results?

A

All of these QC results must be recorded following lab protocol

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25
Q

Is distilled water recommended as a (-) control for QC in rgnt strips?

A

No

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26
Q

If distilled water is recommended or not recommended as (-) control for QC in rgnt strips, why or why not?

A

It is not recommended as a (-) control for QC in rgnt strips because rgnt strip chemical rxns are designed to perform at ionic concentrations similar to urine

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27
Q

What should be done if the QC results do not agree w/ the published values?

A

Retest QC results

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28
Q

What is the normal pH of normal random sxs?

A

4.5 - 8.0

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29
Q

What is the major purpose of lungs and kidneys?

A

They are the major regulators of acid-base content

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30
Q

What is the pH of first morning sx?

A

Slightly acidic: 5.0 - 6.0

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31
Q

When is urine having more alkaline pH occur?

A

These is found following meals (alkaline tide)

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32
Q

pH must be considered in conjunction with what?

A

1) Acid-base content of the blood
2) Pt’s renal function
3) Presence of UTI
4) Pt’s dietary intake
5) Age of sx

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33
Q

Urinary pH is controlled primarily by what?

A

Dietary regulation

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34
Q

Persons on high-protein and high-meat diets produces what pH of urine?

A

Acidic urine

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35
Q

Vegetarians produces what pH of urine?

A

Alkaline urine

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36
Q

Why does vegetarians produce alkaline urine?

A

Due to the formation of bicarbonate following digestion of many fruits and vegetables

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37
Q

True or False

Some medications also may be used to regulate the urine pH

A

True

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38
Q

What are the indications if the pH of urine is above 8.5?

A

1) It is associated w/ an improperly preserved sx

2) It is associated w/ contamination of detergents from reusing containers

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39
Q

What type of urine sx should be obtained to ensure the validity of UA?

A

Fresh sx

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40
Q

What are the clinical significance of urine pH?

A

1) It aids in determining the existence of systemic acid-base disorders of metabolic or respiratory origin
2) It aids in the management of urinary conditions that require the urine to be maintained at a sp pH
3) The precipitation of inorganic chemicals - urinary crystals and renal calculi depends on urinary pH
4) For identification of crystals observed during microscopic examination of the urine sediment
5) Acidic urine is valuable in treating UTIs

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41
Q

What is the principle of pH as chemical pad in the rgnt strip?

A

Double-indicator system of methyl red and bromthymol blue

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42
Q

What is the color rxn for methyl red as a principle for pH as chemical pad in the rgnt strip?

A

Red to yellow in the pH range of 4 - 6

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43
Q

What is the color rxn for bromthymol blue as a principle for pH as chemical pad in the rgnt strip?

A

Yellow to blue in the pH range of 6 - 9

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44
Q

What is the difference in sensitivity (in terms of increments) bet Multistix and Chemstrip?

A

Multistix: 5.0 - 8.5 in 0.5 increments
Chemstrip: 5.0 - 9.0 in 1.0 increments

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45
Q

What type of urine should always be used when measuring the pH?

A

Fresh urine

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46
Q

What is the pH range of fresh urine of healthy people?

A

5 - 7

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47
Q

What are the sources of error in pH chemical pad via the use of rgnt strip?

A

1) No known interfering substances
2) Run-over from adjacent
3) Old sxs

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48
Q

At what chemical tests can pH be correlated?

A

1) Nitrite
2) Leukocyte
3) Microscopic analyses

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49
Q

Is the pH of acidic urine high or low?

A

Lower pH

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50
Q

What are the clinical manifestations of acidic urine (lower pH)?

A

1) Increased protein metabolism (high protein diet)
2) High fever, infections caused by acid producing bacteria (E. coli)
3) Diarrhea
4) Respiratory or metabolic acidosis or ketosis (DM)
5) Starvation and dehydration
6) Medications (methenamine mandelate and fosfomycin tromethamine)
7) Cranberry juice

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51
Q

Is the pH of alkaline urine high or low?

A

Increased pH (high pH)

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52
Q

What are the clinical manifestations of alkaline urine?

A

1) UTIs caused by urease producing bacteria
2) Respiratory or metabolic alkalosis
3) Renal tubular acidosis
4) Vegetarian diet
5) Hyperventilation
6) Vomiting
7) Old sx (prolonged standing)

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53
Q

What is the purpose of urine protein?

A

It is the most indicative of renal disease

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54
Q

Urine protein consists primarily of what?

A

Low molecular weight protein

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55
Q

What is the major serum protein found in normal urine?

A

Albumin

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56
Q

What is the urine protein that a normal urine usually contain?

A

< 10 mg/dL or 100 mg per 24 hrs is excreted

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57
Q

What are other proteins?

A

1) Serum and tubular microglobulins
2) Tamm-Horsfall protein (uromodulin)
3) Proteins from prostatic, seminal, and vaginal secretions

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58
Q

Tamm-Horsfall protein (uromodulin) is produced by what?

A

Renal tubular EC (DCT)

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59
Q

What is proteinuria?

A

A condition wherein there is an increased amt of protein in the urine which is often associated w/ early renal disease

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60
Q

What are the 3 major categories of causes of proteinuria (based on the origin of protein)?

A

1) Prerenal proteinuria
2) Renal proteinuria
3) Postrenal

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61
Q

What causes prerenal proteinuria?

A

It is caused by conditions affecting the plasma prior to its reaching the kidney

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62
Q

Renal proteinuria is associated w/ what?

A

It is associated w/ true renal disease may be the result of either glomerular or tubular damage

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63
Q

What is postrenal proteinuria?

A

It is the protein added to a urine as it passes through the structures of the lower urinary tract

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64
Q

What are the characteristics of prerenal proteinuria?

A

1) It is caused by increased lvls of low-molecular-weight plasma proteins
2) It is not indicative of actual renal disease
3) Indicative of hemolysis
4) Indicative of muscle injury (myoglobin)
5) Acute phase reactants (associated w/ infections and inflammations)
6) Multiple myeloma (Bence Jones protein)

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65
Q

What is Bence Jones protein?

A

A monoclonal globulin protein or immunoglobulin light chains (lamda light chain) found in the urine

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66
Q

What is multiple myeloma (plasma cell myeloma)?

A

It is a proliferative disorder of the plasma cells

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67
Q

What are the characteristics of Bence Jones protein?

A

1) It is filtered in the kidney in high amts, exceeds tubular reabsorption capacity
2) It coagulates at temps between 40 DC and 60 DC and dissolves when the temp reaches 100 DC
3) Confirmed by serum electrophoresis

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68
Q

What are the clinical manifestations of renal proteinuria?

A

1) Glomerular disorders (up to 4 g/day)
2) Immune complex disorders (SLE and Streptococcal glomerulonephritis)
3) Amyloidosis
4) Diabetic nephropathy (Microalbuminuria)
5) Toxic agents
6) Dehydration
7) Hypertension
8) Pre-eclampsia
9) Orthostatic or postural proteinuria
10) High fever
11) Exposure to cold
12) Strenuous exercise

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69
Q

What is tubular proteinuria?

A

These are disorders affecting tubular reabsorption of albumin

70
Q

What is the characteristic of tubular proteinuria?

A

Exposure to toxic substances and heavy metals

71
Q

What are the clinical manifestations of tubular proteinuria?

A

1) Severe viral infections

2) Fanconi syndrome

72
Q

What are the clinical manifestations of postrenal proteinuria?

A

1) Lower UTIs / inflammation
2) Injury / trauma
3) Menstrual contamination
4) Prostatic fluid / spermatozoa
5) Vaginal secretions

73
Q

What is the principle of protein as chemical pad in the rgnt strip?

A

Protein error of indicators

74
Q

What is the principle along w/ the rxn of protein chemical pad in the rgnt strip?

A

The test pad is buffered at constant pH 3 and changes color from yellow to greenish blue in the presence of albumin

75
Q

What is the rgnt in Multistix for protein chemical pad in the rgnt strip?

A

Tetrabromophenol blue (TBP-blue)

76
Q

What is the rgnt in Chemstrip for protein chemical pad in the rgnt strip?

A

Tetrachlorophenol-tetrabromosulfophthalein (TC-TBS)

77
Q

What is the difference in sensitivity for protein chemical pad bet Multistix and Chemstrip?

A

Multistix: 15 - 30 mg/dL albumin
Chemstrip: 6 mg/dL albumin

78
Q

What are the sources of false (+) errors or interferences for protein chemical pad in the rgnt strip?

A

1) Highly buffered alkaline urine
2) Pigmented sxs, phenazopyridine
3) Quaternary ammonium compounds
4) Detergents
5) Antiseptics, chlorhexidine
6) Loss of buffer from prolonged contact of the strip to the sx
7) High SG

79
Q

What are the sources of false (-) errors or interferences for protein chemical pad in the rgnt strip?

A

1) Proteins other than albumin

2) Microalbuminuria

80
Q

At what tests can protein chemical pad in the rgnt strip be correlated?

A

1) Nitrite
2) Blood
3) Leukocytes
4) Microscopic

81
Q

How are readings for protein chemical pad in the rgnt strip reported?

A

1) Negative
2) Trace
3) 1+
4) 2+
5) 3+
6) 4+

82
Q

How are readings for protein chemical pad in the rgnt strip reported (via semiquantitative values)?

A

1) 30
2) 100
3) 300
4) 2000
* all mg/dL

83
Q

What is the purpose of sulfosalicylic acid precipitation test?

A

It is used to confirm doubtful abnormal result

84
Q

What should be considered when evaluating urine protein? Why?

A

SG, because a trace protein in a dilute sx is more significant than in a concentrated sx

85
Q

What is the meaning of SSA?

A

Sulfosalicylic Acid Precipitation Test

86
Q

What are the purposes of SSA?

A

1) Confirmatory test for protein
2) Cold precipitation test that reacts equally w/ all forms of protein
3) Must be performed on centrifuged urine sx to remove any extraneous contamination

87
Q

What are the clinical manifestations of microalbuminuria?

A

1) DM type 1 and 2 kidney disease
2) Diabetic nephropathy
3) Also associated w/ an increased risk of cardiovascular disease

88
Q

What is diabetic nephropathy?

A

Reduced glomerular filtration and eventual renal failure

89
Q

What is the purpose of microalbuminuria?

A

Used to predict early onset of renal complications and the progression of renal disease

90
Q

What are the characteristics of microalbuminuria?

A

1) 30 - 300 mg of albumin/ 24hrs (30 - 300 mcg/mg creatinine)
2) Normal lvl: < 30 mg/24hr

91
Q

Provide an ex of immunologic tests for microalbuminuria?

A

Micral-Test (rgnt strips)

92
Q

What is the principle of Micral-Test?

A

Enzyme immunoassay (Enzyme - Immunochemical assay)

93
Q

What is the sensitivity of Micral-Test?

A

0 - 10 mg/dL

94
Q

What are the rgnts used in Micral-Test?

A

1) Gold-labeled antihuman albumin Ab-enzyme conjugate
2) B-galactosidase
3) Chlorophenol red galactoside

95
Q

What is the false (-) interference of Micral-Test?

A

Dilute urine

96
Q

What sx is used for Micral Test rgnt strip?

A

Random or first morning sxs

97
Q

What is the process (or steps) of Micral Test?

A

Strips are dipped into the urine and held for 5secs
*albumin in the urine binds to the Ab

The urine albumin-bound conjugates reacts w/ the substrate, producing colors ranging from white to red

98
Q

The amt of color produced via micral test represents what?

A

It represents the amt of albumin present in the urine

99
Q

What is done to the color being produced via micral test?

A

The color is compared w/ a chart on the rgnt strip bottle after 1 min
*results range from 0 - 10 mg/dL

100
Q

What is the principle of ImmunoDip (as tests for microalbuminuria)?

A

Immunochromographics

101
Q

What is the sensitivity of ImmunoDip?

A

1.2 - 8.0 mg/dL

102
Q

What is the rgnt for ImmunoDip?

A

Antibody-coated blue latex particles

103
Q

What is the false (-) interference for ImmunoDip?

A

Dilute urine

104
Q

What is the purpose of Clinitest microalbumin strips / Multistix-Pro?

A

1) Simultaneous measurement of albumin and creatinine

2) Provide an estimate of the 24 hr albumin concentrations from random urine sx

105
Q

What is the action of Clinitest microalbumin strips / Multistix-Pro?

A

Albumin pad uses dye binding action for sp albumin testing

106
Q

What is the principle of Clinitest microalbumin strips / Multistix-Pro?

A

Sensitive albumin tests related to creatinine concentration to correct for pt hydration

107
Q

What are the purposes of albumin:creatinine ratio?

A

1) Measures albumin / protein and creatinine that permits an estimation of the 24 hr microalbumin excretion
2) Creatinine measurement is to correlate the albumin concentration to the urine concentration

108
Q

How can albumin reading be corrected?

A

It can be corrected by comparing the albumin excretion to the creatinine excretion

109
Q

What is the sx used for albumin:creatinine ratio?

A

24 hr urine collection

110
Q

What is the principle used in albumin chemical pad in rgnt strips?

A

Albumin rgnt strips use the dye bis (-diiodo-dihydroxy dinitrophenyl)-tetrabromo sulphonphthalein (DIDNTB), w/c has a higher sensitivity

111
Q

What is the color range of rxn for albumin chemical pad in rgnt strips?

A

Pale green to aqua blue

112
Q

What is the sensitivity of albumin in albumin chemical pad in rgnt strip rxns?

A

10 - 150 mg/L

113
Q

What is the interference present in albumin chemical pad in rgnt strips?

A

Visibly bloody or abnormally colored urine (falsely elevated result)

114
Q

What is the principle of creatinine chemical pad in rgnt strip?

A

Pseudoperoxidase activity of copper-creatinine complexes

115
Q

What are the rgnts used in creatinine chemical pad in rgnt strips?

A

1) Copper sulfate (CuSO4)
2) 3,3’,5,5’-tetram-ethylbenzidine (TMB)
3) diisopropyl benzene dihydroperoxide (DBDH)

116
Q

What is the sensitivity in creatinine chemical pad in rgnt strips?

A

10 - 300 mg/dL (0.9 - 26.5 mmol/L)

117
Q

What is the color rxn in creatinine chemical pad in rgnt strips?

A

Orange through green to blue

118
Q

What are the interferences in creatinine chemical pad in rgnt strips?

A

Visibly bloody or abnormally colored urine

False (+): Cimetidine

119
Q

What is the principle of glucose oxidase rxn?

A

Double sequential rxn of glucose oxidase and peroxidase

120
Q

What are the principle of rxns for glucose oxidase rxn?

A

Stage-I
Glucose + Oxygen (room air) (via the action of glucose oxidase) -> Gluconic acid + Hydrogen peroxide

Stage-II
Hydrogen peroxide + Chromogen (via the action of peroxide) -> Oxidized chromogen (Blue) + H2O

121
Q

What are the rgnts used in glucose oxidase rxn (Multistix)?

A

1) Glucose oxidase

2) Peroxidase

122
Q

What is the chromogen used in glucose oxidase rxn (Multistix)?

A

Potassium iodide

123
Q

What is the color rxn brought by potassium iodide in glucose oxidase rxn (Multistix)?

A

Green to brown

124
Q

What is the sensitivity in glucose oxidase rxn (Multistix)?

A

75 - 125 mg/dL

125
Q

What are the manners of reporting in glucose oxidase rxn (Multistix)?

A

1) Negative
2) Trace
3) 1+
4) 2+
5) 3+
6) 4+

126
Q

What are the quantitative measurements in glucose oxidase rxn (Multistix)?

A

From 100 mg/dL to 2 g/dL or 0.1% to 2%

127
Q

What are the rgnts used in glucose oxidase rxn (Chemstrip)?

A

1) Glucose oxidase

2) Peroxidase

128
Q

What is the chromogen used in glucose oxidase rxn (Chemstrip)?

A

Tetramethylbenzidine

129
Q

What is the color rxn brought by the chromogen in glucose oxidase rxn (Chemstrip)?

A

Yellow to green

130
Q

What is the sensitivity in glucose oxidase rxn (Chemstrip)?

A

40 mg/dL

131
Q

What are the manners of reporting in glucose oxidase rxn (Chemstrip)?

A

1) Negative
2) Trace
3) 1+
4) 2+
5) 3+
6) 4+

132
Q

What are the quantitative measurements in glucose oxidase rxn (Chemstrip)?

A

From 100 mg/dL to 2 g/dL or 0.1% to 2%

133
Q

What is the false (+) interference in glucose oxidase rxn?

A

Contamination by oxidizing agents and detergents

134
Q

What are the false (-) interferences in glucose oxidase rxn?

A

1) High lvls of ascorbic acid
2) High lvls of ketones
3) High SG
4) Low temps
5) Improperly preserved sxs (at room temp)

135
Q

The urine glucose can be correlated in what tests?

A

1) Ketones

2) Protein

136
Q

What are the purposes of copper reduction test (Clinitest)?

A

1) Measurement of glucose by the copper reduction method

2) Used for sugar other than glucose (Galactosuria)

137
Q

What is the principle of action in Clinitest?

A

Glucose reduces copper sulfate to cuprous oxide in the presence of alkali and heat

138
Q

What is the result in Clinitest?

A

Color change progressing from a (-) blue CuSO4 through green, yellow, and orange / red (CU20)

139
Q

What are the components of Clinitest tablets?

A

1) Copper sulfate
2) Sodium carbonate
3) Sodium citrate
4) Sodium hydroxide

140
Q

What is the sensitivity in Clinitest?

A

200 mg/dL glucose >

141
Q

What are the principle of actions in copper reduction test?

A

CuSO4 (cupric sulfide) + reducing substance (in the presence of heat) ->

Cu2O (cuprous oxide) + oxidized substance (in the presence of alkali) -> color (blue / green to orange / red)

142
Q

What are the interpretations of various color rxns in Clinitest?

A

1) Blue solution: none
2) Green / yellow ppt: traces of reducing sugar
3) Orange red ppt: moderate
4) Brick-red ppt: large amt of reducing sugar

143
Q

What is the source of error and interference in Clinitest?

A

“Pass through” phenomenon

144
Q

When does pass through phenomenon occur (in Clinitest)?

A

It may occur at very high glucose lvl

145
Q

What is the principle of action of pass through phenomenon (in Clinitest)?

A

The color produced passes through the orange / red stage and returns to a green-brown color

146
Q

What will happen if pass through phenomenon (in Clinitest) is not observed?

A

If not observed, a high glucose lvl may be reported as (-)

147
Q

What should be done to minimize the occurrence of pass through phenomenon in Clinitest?

A

Use 2 drops instead of 5 drops of urine

148
Q

What are the diff interfering substances in Clinitest?

A

1) Galactose
2) Lactose
3) Fructose
4) Maltose
5) Pentoses
6) Ascorbic acid
7) Certain drug metabolites
8) Antibiotics (cephalosporins)

149
Q

What are the rgnts used in Benedict’s test?

A

1) CuSO4
2) Na carbonate
3) Na citrate

150
Q

What is the purpose of Na citrate in Benedict’s test?

A

It acts as a buffer

151
Q

What is the principle of action in Benedict’s test?

A

Heating a mixture of Benedict’s rgnt and reducing sugar (glucose) in a basic medium (pH 10.5) leads to the reduction of cupric ions to cuprous ions w/ the formation of copper oxide (yellow to red ppt)

152
Q

What are the diff interpretations of various color rxns in Benedict’s test?

A

1) Blue solution
- > Nil
2) Green solution
- > trace
- > < 500 mg/dL
3) Green ppt
- > (+)
- > 500 - 1000 mg/dL
4) Yellow ppt
- > (++)
- > 1000 - 1500 mg/dL
5) Orange ppt
- > (+++)
- > 1500 - 2000 mg/dL
6) Red-Brick red ppt
- > (++++)
- > 2000 md/dL >

153
Q

What are the various glucose oxidase results w/ corresponding Clinitest interpretations of rxns and interpretations?

A

Glucose oxidase: 1+
Clinitest: negative
Interpretation: small amt of glucose present

Glucose oxidase: 4+
Clinitest: negative
Interpretation: possible oxidizing agent interference on strip

Glucose oxidase: negative
Clinitest: positive
Interpretation: non-glucose reducing subs and interfering substance for rgnt strip

154
Q

What are the hyperglycemia-associated clinical significance of urine glucose?

A

1) DM
2) Pancreatitis
3) Pancreatic cancer
4) Acromegaly
5) Cushing syndrome
6) Hyperthyroidism
7) Pheochromocytoma
8) Central nervous system damage
9) Stress
10) GDM

155
Q

What are the renal associated clinical significance of urine glucose?

A

1) Fanconi syndrome
2) Advanced renal disease
3) Osteomalacia
4) Pregnancy

156
Q

What are the 3 intermediate products of fat metabolism in connection to ketones?

A

1) Acetone
2) Acetoacetic acid
3) Beta(sign)-hydroxybutyrate

157
Q

What is the % distribution of acetone as intermediate products of fat metabolism?

A

2%

158
Q

What is the % distribution of acetoacetic acid as intermediate products of fat metabolism?

A

20%

159
Q

What is the % distribution of beta(sign)-hydroxybutyrate as intermediate products of fat metabolism?

A

78%

160
Q

When is ketones in urine detected?

A

These are detected in the urine when body stores of fat must be metabolized to supply energy

161
Q

When is urine ketones most valuable?

A

These are most valuable in the management and monitoring of insulin-dependent (type 1) DM

162
Q

What are the principle of actions in ketones chemical pads in rgnt strips?

A

Rgnt strip tests use the sodium nitroprusside (nitroferricyanide) rxn to measure ketones

Acetoacetic acid in an alkaline medium reacts w/ sodium nitroprusside to produce a purple color

163
Q

What are the rgnts used in ketones chemical pad in rgnt strips?

A

1) Sodium nitroprusside

2) Glycine (Chemstrip)

164
Q

What is the sensitivity of ketones chemical pad in Multistix rgnt strips?

A

5 - 10 mg/dL acetoacetic acid

165
Q

What is the sensitivity of ketones chemical pad in Chemstrip rgnt strips?

A

9 mg/dL acetoacetic acid | 70 mg/dL acetone

166
Q

What are the false (+) interferences in ketones chemical pad in rgnt strips?

A

1) Phthalein dyes
2) Highly pigmented red urine
3) Levodopa
4) Medications containing free sulfhydryl grps

167
Q

What is the false (-) interference in ketones chemical pad in rgnt strips?

A

Improperly preserved sxs

168
Q

At what chemical test can ketones be correlated?

A

Glucose

169
Q

How and what are the manners of reporting for results of ketones chemical pad in rgnt strips?

A

Results are reported qualitatively as negative, trace, small (1+), moderate (2+), or large (3+)

Semi-quantitatively: negative, trace (5 mg/dL), small (15 mg/dL), moderate (40 mg/dL), or large (80 - 160 mg/dL)

170
Q

What does ketonuria present and what is the resolution that should be done?

A

It presents deficiency in insulin w/c indicates the need to regulate the dosage

171
Q

What is the purpose of ketones chemical pad in rgnt strips?

A

It is often an early indicator of insufficient insulin dosage in type 1 diabetes and in pts w/ diabetes

Analysis of Urine and Other Body Fluids (Laboratory) (9 decks)

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