Chemical Examination Of Urine Flashcards
1
Q
Urine parameter/s that is read at 30 sec
A
Glucose and Bilirubin
2
Q
Ketones are read at how many seconds?
A
40 seconds
3
Q
Specific gravity is read at how many seconds?
A
45 seconds
4
Q
Give the 5 urine parameters read at 60 seconds
A
Protein, pH, blood, urobilinogen, nitrite
5
Q
The longest to urine parameter to read (give the time and parameter)
A
Leukocytes = 120 seconds
6
Q
What is the purpose of a desiccant in an opaque tightly closed container for reagent strips
A
It absorbs moisture
7
Q
Reagent strips should be stored below __.
A
Below 30C (do not freeze)
8
Q
Principle behind automated reagent strip readers
A
Reflectance photometry
9
Q
Normal specific gravity in a normal random urine
A
1.003-1.035
10
Q
The specific gravity when radiographic dye is present
A
> 1.040
11
Q
Complete the equation:
Isosthenuria: SG __ 1.010
Hyposthenuria: SG __ 1.010
Hyper strenuous: SG __ 1.010
A
Isosthenuria SG = 1.010
Hyposthenuria SG <1.010
Hypersthenuria SG >1.010
12
Q
Needed volume for urinometer and the calibration temperature
A
10-15* mL ; 20C
13
Q
Refractometry utilizes what principle
A
Refractive index
14
Q
TRUE/ FALSE
Refractometer needs temperature correction, but does not require glucose and protein correction
A
FALSE.
- temperature correction is not required
- glucose and protein correction is required
15
Q
Give the calibration for the refractometer specific gravity:
- Distilled water
- 3% NaCl
- 5% NaCl
- 7% NaCl
- 9% Sucrose
A
- Distilled water - 1.000
- 3% NaCl - 1.015 +/- 0.001
- 5% NaCl - 1.022 +/- 0.001
- 7% NaCl - 1.035 +/- 0.001
- 9% Sucrose - 1.034 +/- 0.001
16
Q
The principle behind reagent strip reaction for SpGr
A
Change in dissociation constant (pKa)
17
Q
A 1.000 SpGr indicates a __ color; a 1.030 SpGr indicates a __ color
- SG strip sensitivity = 1.000-1.030
A
1.000 = blue ; 1.030 = yellow
18
Q
Reagent utilized in SpGr strip
A
Poly* Bromthymol blue
Ethyl * Bromthymol blue
19
Q
Harmonic oscillation density meter is based on the frequency of ___, and requires ___ mL urine volume in which ___ mL is utilized for IRIS Mass Gravity Meter
A
Soundwave ; 6mL ; 2mL
20
Q
What does IRIS stand for
A
International Remote Imaging System
21
Q
A high concentration of __ may yield a false (+) in the determination of SpGr; while a/n __ may yield a false (-)
A
Protein (+)
Highly alkaline urine (pH>/=6.5) (-)
22
Q
A pH of 9 signifies a __
A
Unpreserved urine
23
Q
Normal pH in random specimen and 1st morning specimen
A
Random 4.5-8.00
First morning 5.0-6.0
24
Q
Principle of the reagent strip reaction for pH, and give the reagents
A
Double indicator system; methyl red and bromthymol blue
25
This parameter is the most indicative of renal disease
Protein
26
Protein in urine produces (yellow/white) foam in urine when shaken
White foam
27
Major serum protein found in urine ; give the normal excretion rate
Albumin (<150mg/Day)
28
Proliferation of Ig-producing plasma cells
Multiple myeloma
29
This protein is seen and is indicative of multiple myeloma. In the urine, this protein precipitates at __ and dissolves at __.
Bence-Jones protein (precipates at 40-60C; dissolves at 100C)
30
Glomerular proteinuria is caused by what disease
Diabetic nephropathy
31
Normal albumin excretion rate
0-20 ug/min
32
Indicator for glomerular nephropathy (give the AER)
Microalbuminuria (20-200 ug/min)
33
A >200 ug/min AER indicates ___ albuminuria
Clinical albuminuria
34
Test for microalbuminuria which utilizes _ principle
Micral test ; enzyme immunoassay
35
Reading time for micral test and a the color that indicates a positive reaction
60 s; red
36
Orthostatic proteinuria shows a __ of protein in 1st morning specimen and a __ protein after 2 hrs. standing
Negative ; positive
37
Principle behind protein reagent strip
Protein sorensen’s error of indicators
38
Reagent for protein strip
Citrate buffet at pH 3.00
39
A high specific gravity will yield a false _ result in the determination of protein
False positive
40
Indicator for protein (protein sorensens error of indicators) is highly sensitive to _
Albumin ONLY
41
Test used to measure all forms of proteins
Sulfosalicylic acid (SSA) precipitation test
42
Most frequently tested in urine
Glucose (dextrose)
43
It is a defective tubular reabsorption of glucose and amino acids
Fanconi syndrome
44
Principle for glucose strip
Double sequential enzyme reaction
45
Sensitivity of reagent strip to glucose is __ mg/dL
100 mg/dL
46
Copper reduction test is also called as __
Clinitest/ Benedict’s Test
47
This test is a nonspecific test for reducing sugars
Copper reduction test
48
True / False
| Clinitest can detect all sugars
False. It cannot detect SUCROSE
49
To prevent pass through phenomenon, what should be done
Lower the volume (5gtts —> 2gtts)
50
Give the percent composition of ketone bodies
1. Beta-hydroxybutyric acid
2. Acetoacetic acid / diacetic acid
3. Acetone
1. 78% = Beta-hydroxybutyric acid
2. 20% = Acetoacetic acid / diacetic acid
3. 2%= Acetone
51
Parent ketone
AAA
52
Major ketone but is not detected in the reagent strip
Betahydroxybutyric acid
53
Principle employed in ketone reagent strip
Sodium nitroprusside reaction
54
Why is mixing a urine specimen prior to testing important
So that formed elements will not settle at the bottom, and be detected
55
Reagent strips should be dipped in an uncentrifuged / centrifuged urine at __ temperature
Uncentrifuged; room temperature
56
Why do specimens that have been refrigerated be allowed to return to room temp before reagent strip testing
Because enzymatic reactions on the strip are temperature dependent
57
Reagent bottles should not be opened in the presence of __
Volatile fumes
58
Reagent strips must be tested with both (+) and (-) controls a minimum of once every __
24 hrs
59
True / false
| Distilled water is recommended as a negative control for reagent strips
False. Strips are designed to follow an ionic concentrations similar to urine
60
Persons taking phenazopyrodine compounds may interfere the strip reaction due to the ___ colored urine
Orange pigment
61
What are the major regulators of the acid-base content in the body
Kidney and lungs
62
Refers to a more alkaline urine pH following a meal
Alkaline tide
63
In respiratory / metabolic acidosis not relations to renal function disorder, urine is __
Acidic
64
True / False
urinary pH that does not conform to the respiratory / metabolic pH may indicate a disorder of the kidneys to reabsorb / secrete acids or bases
TRUE
65
True / False
| Bacteria readily multiply in acidic urine
False. Bacteria favors alkaline
66
Persons on high protein and high meat diets tend to have acidic / basic urine; while vegetarians tend to have an acidic / alkaline urine
Acidic ; alkaline
67
Hyperventilation yields an acidic/alkaline urine
Alkaline
68
Renal tubular acidosis yields an acidic/alkaline urine
Alkaline
69
In the pH reagent strip reaction, methyl red produces a color change from red to yellow in the pH of __; while bromthymol blue produces a color change from yellow to blue in the pH of __.
Red to yellow: 4-6 pH
| Yellow to blue: 6-9 pH
70
pH range of the reagent strip
5-9
71
Proteinuria is often associated with __.
Early renal disease
72
This protein is produced by the renal tubular epithelial cells (give its new name as well)
Tamm-Horsfall protein (uromodulin)
73
Where specifically is uromodulin produced?
Distal convoluted tubule
74
This type of proteinuria is NOT indicative of renal disease. It is caused by increased levels of plasma proteins (myoglobin/hemoglobin), and the acute phase reactants in the blood.
Prerenal Proteinuria
75
True / False: Bence Jones protein is seen in renal proteinuria
False. Bence Jones protein is associated with Multiple myeloma (increased proteins (Ig) in the blood) therefore it is seen in PRE-RENAL PROTEINURIA.
76
Proteinuria associated with true renal disease
Renal proteinuria
77
True / False:
Amyloid material and the immune complexes found in SLE and streptococcal glomerulonephritis are major causes of proteinuria due to glomerular damage
True
78
True/ False:
Increased pressure from the blood entering the glomerulus may override the selective filtration of the glomerulus, causing increased albumin to enter the filtrate. This condition is irreversible.
False. This condition is REVERSIBLE (e.g. exercise, dehydration, hypertension)
79
Benign/malignant proteinuria is produced in conditions such as strenuous exercise, high fever, dehydration, and exposure to cold.
Benign
80
Patients with microalbuminuria are associated with an increased risk of __.
Cardiovascular disease
81
In orthostatic/ postural proteinuria (benign), increased pressure on the renal vein when in the __ position is believed to account for this condition.
Vertical / Standing
82
Fanconi syndrome is classified under which type of proteinuria? (orthostatic/glomerular/tubular/pre-renal)
Tubular. *Defective tubular reabsorption of glucose and AAs
83
True / False:
The presence of blood (e.g. injury/menstrual contamination) as well as prostatic fluid and large amounts of spermatozoa may contribute to protein
True
84
Why is the protein reagent strip more specific to albumin?
Albumin contains more amino groups to accept the Hydrogen ions from the indicator
85
__ color indicates the absence of protein
Yellow
86
Trace values of protein are considered to be less than __ mg/dL
<30 mg/dL
87
A false-positive reaction for protein may be due to: (2)
1. Highly Alkaline urine
| 2. High Specific Gravity
88
Sulfosalicylis Acid Precipitation reacts equally to all forms of __
Proteins
89
Specimen for SSA
Centrifuged urine
90
Reagent for micral-test
Gold-labeled antihuman albumin antibody-enzyme conjugate
91
How many seconds is the strip for the micral test dipped in the urine?
5 seconds
92
Proteins other than Albumin will yield a false __ result in the protein determination
Negative
93
Microalbuminuria will yield a false __ result in the protein determination
Negative
94
Immunodip reagent strip uses ___ technique. This is also for the determination of ___.
Immunochromatographic technique; Protein (albumin)
95
In the immunodip reagent strip, a darker bottom band is __, equal band color is __, and a darker top band represents a __ result.
Bottom - negative
Equal - borderline
Top - positive
96
True / False:
By comparing the albumin excretion to the creatinine excretion, the albumin reading can be corrected for over-hydration and dehydration in a random sample.
True. Creatinine is produced and excreted at a consistent rate.
97
The reagent strip for creatinine follows the same principle as the reaction for __
Blood
| * Creatinine strip principle: Psuedoperoxidase activity of copper-creatinine complexes
98
Normal creatinine concentration in the urine
10-300 mg/dL
99
Glucose is actively reabsorbed at __
Proximal convoluted tubule
100
It refers to the blood level at which tubular reabsorption stops.
Renal Threshold
101
Renal threshold of glucose
160-180 mg/dL
102
True/False
| Fasting is not necessary when testing for glucose
FALSE. The most informative glucose results are obtained from specimens collected under controlled conditions (avoiding glycosuria following meals)
103
For purpose of diabetes monitoring, specimens are usually tested __ min/hrs after meals
2 hrs.
104
Hyperglycemia that occurs during pregnancy
Gestational diabetes
105
The onset of hyperglycemia and glycosuria is usually on the __ month of pregnancy
```
6th month (2nd trimester)
* hormones secreted by the placenta block the action of insulin
```
106
True or false: Insulin can pass the placenta
FALSE. Only glucose can pass the placenta
107
Babies who are affected by gestational diabetes
Macrosomia (large baby)
108
The primary function of insulin
Glycogenesis (glucose-> glycogen)
109
This refers to glycosuria in the absence of hyperglycemia
Renal glycosuria
110
Intermediate product of the reagent strip glucose oxidase reaction
Gluconic acid and peroxidase
111
False-positive reactions for glucose may be a result of _.
Contamination by oxidizing reagents
112
Contamination of ascorbic acid for glucose strip may result in a false _ reaction
Negative
| * Ascorbic acid prevents the oxidation of the chromogen
113
The greatest source of error for false (-) for glucose strip
Technical error of allowing specimens to remain unpreserved at room temperature for extended periods
114
Reagents of Benedict Solution
1. Copper sulfate
2. Sodium bicarbonate
3. Sodium citrate buffer
115
True/False
| Clinitest can provide confirmatory testing for glucose
False.
116
This type of sugar in the urine of a newborn represents an inborn error of metabolism
Galactose
117
Galactose in the urine of a newborn may indicate that there is a lack of the enzyme called _ which prevents the breakdown of ingested galactose which often leads to death
galactose-1-phosphate uridyl transferase
118
Clinitest is performed on pediatric specimens from patients up to __.
At least 2 years of age
119
A phenomenon that occurs at high glucose levels wherein the orange/red stage returns to a __ color, and may be reported as __.
Pass through phenomenon; greenish-brown color; negative
120
Testing for ketones is most valuable in the management and monitoring of Type __ DM.
Type I (Insulin-dependent)
121
Ketonuria signifies a deficiency in __
Insulin
122
Positive color that indicates the presence of Protein
Blue
123
Positive color that indicates the presence of Ketones
Purple
124
Confirmatory test for ketones
Acetest tablet test
125
Blood present in the urine in intact red blood cells
Hematuria
126
Blood present in the urine as the product of RBC destruction
Hemoglobinuria
127
How to differentiate hematuria and hemoglobinuria?
Hematuria: Cloudy red urine
Hemoglobinuria: Clear red urine
128
Blood gathered at _uL of urine is clinically significant
>5 microliters of urine
129
True/False:
| Microscopic tests provide the most accurate means for determining the presence of blood.
False. Chemical tests provide the most accurate means for determining the presence of blood. Free hemoglobin is NOT seen in microscopic examination.
130
A (+) reagent strip test for blood indicates the presence of __, __, and __.
RBCs, Hemoglobin, Myoglobin
131
Patients with severe back and abdominal pain are suspected of having __.
Renal calculi
132
Hemoglobinuria may be produced in the urinary tract as a product of ___ urine.
dilute, alkaline urine
133
Reabsorption of filtered hemoglobin results in the appearance of large, yellow-brown granules of denatured ferritin called __
Hemosiderin
134
Color of urine in myoglobinuria
Clear red-brown urine (at atleast 25mg/dL myoglobin0
135
Patients with this condition are suspected of myoglobinuria
Rhabdomyolysis
136
True/False
| The heme portion of myoglobin is toxic to the renal tubules, and high concentrations can cause renal failure.
True
137
Chromogen for blood reagent strip
Tetramethylbenzidine
138
Used to differentiate myoglobinuria and hemoglobinuria
Blondheim's test
| ** Hemoglobinuria will yield a red precipitate
139
A uniform green-blue in the Blood strip indicates __, while a speckled pattern indicates __.
```
Uniform = Hemoglobin
Speckled = RBCs
```
140
In plasma examination, a red/pink plasma indicates _, while a pale yellow plasma indicates _.
Red/pink = hemoglobin
| Pale yellow = myoglobin
141
Vitamin C yields a false _ reaction in the blood reagent strip
Negative
142
Escherichia coli will yield a __ reaction in the blood reagent strip.
Positive (because of its peroxidase enzyme)
143
Neutralizes Ascorbic acid
Iodate
144
This parameter may provide an early indication of liver disease
Bilirubin
145
Bilirubin in its unconverted form
Protoporphyrin
146
The kidneys cannot excrete bilirubin because _.
1. Bilirubin is bound to albumin *(-) charge
| 2. Bilirubin is water insoluble
147
Water-insoluble bilirubin
Unconjugated bilirubin
148
Converts water-insoluble bilirubin to water-soluble bilirubin
Glucoronyl transferase
149
True/False:
| Conjugated bilirubin is normally found in the urine because it is water-soluble.
FALSE. Conjugated bilirubin is passed to the intestine where intestinal bacteria reduce bilirubin to urobilinogen, which is then oxidized and excreted as STERCOBILINOGEN & UROBILINOGEN
150
this type of bilirubin can appear in the urine when the normal degradation cycle is disrupted by bile duct obstruction (post-hepatic jaundice) or when the integrity of the liver is damaged (hepatic jaundice)
Conjugated bilirubin
151
Indicate if pos/neg/normal:
LIVER DAMAGE
Urine Bilirubin: _
Urine Urobilinogen: _
LIVER DAMAGE:
Urine Bilirubin: +/-
Urine Urobilinogen: ++
152
Indicate if pos/neg/normal:
BILE DUCT OBSTRUCTION
Urine Bilirubin: _
Urine urobilinogen: _
BILE DUCT OBSTRUCTION
Urine Bilirubin: +++
Urine Urobilinogen: Normal
153
Indicate if pos/neg/normal:
HEMOLYTIC DISEASE
Urine Bilirubin: _
Urine urobilinogen: _
HEMOLYTIC DISEASE
Urine Bilirubin: Negative
Urine urobilinogen: +++
154
TRUE / FALSE: Jaundice due to increased destruction of RBCs produces bilirubinemia.
FALSE. Serum bilirubin is present in the unconjugated form and the kidneys CANNOT excrete it.
155
Principle for Bilirubin strip test
Diazo Reaction
156
Positive color for bilirubin strip test
Tan or Pink to Violet
157
The presence of Indican and metabolites of the medication __ will cause a false positive reading in the Bilirubin test
Lodine
158
Bilirubin rapidly oxidized to _ in the presence of light
Biliverdin
159
TRUE/FALSE:
| Biliverdin is unreactive to diazo tests
True
160
Confirmatory test for bilirubin
Ictotest
161
An amount of _ mg/dL or Ehrlich unit of urobilinogen is normally found in the urine
<1 mg/dL
162
Increased urine urobilinogen is seen in __ and __
Liver disease and hemolytic disorders
In liver disease, the ability of the liver to process the urobilinogen recirculated from the blood is impaired, thus excess urobilinogen remaining in the blood is filtered by the kidneys and appears in the urine
In hemolytic disorders, there is an increased amount of unconjugated bilirubin. This UB is presented to the liver for conjugation, which results in an increased CB entering the intestine. As a result, increased urobilinogen is produced
163
Patients who lack the pigment urobilin have a __ characteristic stool.
Pale stool
164
Principle of urobilinogen strip
Ehrlich reaction
165
Component of Ehrlich reagent
p-dimethylaminobenzaldehyde (PDAB)
166
Convertion factor of urobilinogen in mg/dL to Ehrlich units
1
167
Differentiates urobilinogen (UBG), Porphobilinogen (PBG), and other Erlich Reactive compounds (ERCs)
Watson-Schwartz Test
168
Watson-Schwartz Test utilizes the organic solvents __ and __
Chloroform and Butanol
| ** CHLOROFORM BELOW BUTANOL ABOVE
169
A rapid screening test for porphobilinogen
Hoesch Test (Inverse Ehrlich Reaction principle)
170
A parameter that provides rapid screening test for UTI
Nitrite
171
Initial bladder infection
Cystitis (lower urinary tract)
172
The inflammatory process of the kidney
Pyelonephritis (upper urinary tract)
173
True/False
| Pregnant women are considered to be of high risk for UTI
True
174
Nitrite test is combined with _ test to determine the necessity of performing urine culture.
Leukocyte esterase test
175
Principle for nitrite reagent strip test
Greiss reaction
176
Positive reaction for nitrite
Uniform pink
177
Sensitivity of nitrite test
100,000 organisms per mm (corresponding with a quantitative bacterial culture)
178
Results in nitrite is reported as neg, trace, +, ++, +++ / or through color degree
False. Nitrite test are only reported as POSITIVE/ NEGATIVE
179
Bacteria that lack the enzyme _ do not possess the ability to reduce nitrate to nitrite
Reductase
| * Reductase is found in gram (-) bacteria - E.g. Enterobacteriaceae which causes UTI
180
Nitrite tests should be performed on first morning specimens or specimens collected after urine has remained in the bladder for at least _ hrs.
4 hrs.
| ** Bacteria capable of reducing nitrate must remain in contact with urinary nitrate long enough to produce nitrite
181
Reduction of nitrite to nitrogen due to large numbers of bacteria causes a false _ reaction
False-negative
182
Can the LE reagent strip test detect the presence of lysed leukocytes
Yes.
183
The LE test can detect esterase in granulocytic WBCs, and monocytes EXCEPT _
Lymphocytes
184
True/False
| Esterase is also present in Trichomonas and histiocytes
True
185
Infections produced by _, _, _, and _ produce leukocyturia WITHOUT bacteriuria
1. Chlamydia
2. Trichomonas
3. Yeast
4. Interstitial nephritis
186
Reagent for Leukocyte esterase test
Diazonium salt
187
Principle for Leukocyte esterase test
Leukocyte Esterase Reaction
188
A >500mg/dL protein, >3g/dL glucose, oxalic acid, and ascorbic acid yields a false _ result in the LE test
False-negative
189
Ascorbic acid causes false-negative reactions on: (5 parameters)
BB LNG
- Blood
- Bilirubin
- Leukocytes
- Nitrite
- Glucose
