Exam 2 Flashcards
(155 cards)
1
Q
What are the physical properties of urine?
A
Color, Clarity, Foam (not reported), Odor, Concentration, Volume
2
Q
What is urochrome and what is its color?
A
It is a normal product of metabolism and it is yellow.
3
Q
What is urobilin and what color is it?
A
Normal urine constituent; orange-brown pigment
4
Q
What is uroerythrin? What color is it?
A
Normal urine constituent that has a brick dust appearance; pink pigment
5
Q
What may cause a urine sample to be orange?
A
phenazopyridine, warfarin/rifampin, or consumption of carotene
6
Q
What may cause a urine sample to be bright yellow?
A
riboflavin or b-vitamins
7
Q
What may cause a urine sample to be yellow-brown?
A
nitrofurantoin (antibiotic)
8
Q
What may cause a urine sample to be pink?
A
Blood in urine, presence of porphobilin
9
Q
What may cause urine samples to be red?
A
RBCs or HGB, beet ingestion, senna (laxative)
10
Q
What may cause a urine sample to be red-purple?
A
oxidation of phorphobilinogen to colored compounds or improper storage
11
Q
What may cause a urine sample to be brown?
A
myoglobin in the urine, methemoglobin, or metronidazole
12
Q
What may cause a urine sample to be dark brown to black?
A
malignant melanoma, homogentistic acid (alkaline urine)
13
Q
What may cause a urine sample to be blue or green?
A
Pseudomonas infection, methylene blue, chlorophyll, amitriptyline, or indomethacin
14
Q
What may cause a urine sample to be dark yellow-green?
A
biliverdin
15
Q
What may cause a urine sample to be dark yellow or amber?
A
concentrated, excessive urobilin, or bilirubin
16
Q
Is foam reported on a urinalysis?
A
No
17
Q
What does large amounts of foam indicate after a urine sample is shaken up?
A
Presence of protein or bilirubin
18
Q
What does thick, large volume of white foam in urine indicate?
A
Large amounts of protein (albumin) in the urine
19
Q
What does yellow foam in urine indicate?
A
Bilirubin in the urine
20
Q
Describe “clear” urine
A
No particles present, transparent
21
Q
Describe “hazy/slightly cloudy” urine
A
Visible particles are present, newsprint can be read when viewed through urine tube
22
Q
Describe “cloudy” urine
A
Significant particulate matter, newsprint is blurred/difficult to read
23
Q
Describe “turbid” urine
A
Opaque - newsprint cannot be seen when viewed through urine tube
24
Q
Is urine odor reported?
A
No
25
What is the cause of mousy/barny urine odor?
Phenylketonuria
26
What is the cause of sweet/fruity urine odor?
Ketone production due to diabetes mellitus
27
What is the cause of bleach-smelling urine?
Adulteration of specimen (I.e. drug testing)
28
What is the cause of ammoniacal smelling urine?
"old" urine/improperly stored
29
What is the smell of normal urine?
Faintly aromatic
30
What foods can change the smell of urine?
Asparagus, garlic, onions
31
What is the cause of menthol-smelling urine?
Phenol-containing medications
32
What two tests are used to indicate urine concentration?
Specific Gravity or Osmolality
33
Specific gravity
the mass of solutes present in urine
34
Osmolality
the number of solutes present in a solution
35
Is specific gravity or osmolality more specific when it comes to measuring urine concentration?
osmolality
36
What is the physiological possible range of specific gravity of urine?
1.002 - 1.040
37
Specific gravity is a measure of urine _______.
density
38
Refractometry
used to measure SG based on refractive index of light
39
T/F: Refractometry measures ALL solutes in a solution, as opposed to only ionic solutions on a dipstick SG test.
True
40
What factors affect the refractive index of a solution?
Wavelength of light used
Temperature of the solution
Concentration of the solution
41
Each g/dL of protein present increases SG by ____.
0.003
42
Each g/dL of glucose present increases SG by ____.
0.002
43
What may cause physiological impossible SG results?
Presence of radiographic contrast media
44
What limitation does the reagent strip method for SG have?
It only measures ionic specific gravity (charged solutes). It disregards protein, glucose, urea, and radiographic media.
45
Acidic urine causes SG to falsely ______.
increase
46
Alkaline urine causes SG to falsely ______.
decrease
47
What is normal urine osmolality?
275-900 mOsm/kg
48
Does molecular weight have an affect on specific gravity or osmolality?
It has an affect on SG. It does not have an affect on osmolality because osmolality measures # of solutes, not mass.
49
Would NaCl (MW 58) or Glucose (MW 180) have a higher osmolality?
NaCl would have a higher osmolality because it dissociates in solution into 2 osmoles. Glucose does not dissociate in solution.
50
What are the 4 colligative properties?
Freezing point depression
Vapor pressure depression
Osmotic pressure elevation
Boiling point elevation
51
If you were given a sample's freezing point, how would you determine osmolality? (calculation)
1000 X CROSS MULTIPLY :)
____ = ____
-1.86 C freezing point
52
nocturia
when an individual excretes >500mL urine at night
53
anuria
complete lack of urine excretion
54
oliguria
decrease in urine excretion (<400 mL/day)
55
polyuria
excretion of >3L of water daily (excess)
56
diuresis
increase in urine excretion (>1800mL/day)
57
List the 11 possible tests included on a reagent strip for chemical testing.
pH, protein, glucose, blood, leukocyte esterase, specific gravity, bilirubin, urobilinogen, nitrite, ascorbic acid, ketones
58
Reagent strips must be protected from:
moisture, chemicals, heat, and light
59
hyposthenuric
urine with a SG <1.010
60
hypersthenuric
urine with a SG >1.010
61
Normal urine SG range
1.010-1.025
62
isosthenuria
SG of 1.010
63
principle of specific gravity reagent strip test
reagent strip test that only measures ionic (charged) solutes
64
urine pH range
4.5-8.0
65
principle of pH reagent strip test
a double-indicator system using bromothymol blue and methyl red
66
alkaline tide
urine is more alkaline following a meal
67
common reasons for pH over 8.0 (impossible)
improper storage, highly alkaline substance ingested, or adulterated specimen
68
What tests should be negative in urine?
protein, glucose, nitrite, leukocyte esterase, ketones, bilirubin, and blood
69
proteinuria (what is it and what is it caused by)
increased amount of protein in the urine, caused by increased levels of albumin (first indicator of renal disease)
70
Cause of Prerenal proteinuria
caused by increased quantities of plasma proteins
71
glomerular proteinuria
tubular capacity for reabsorption (Tm) is exceeded
72
tubular proteinuria
tubular reabsorptive function is altered or impaired; plasma proteins that are normally reabsorbed will be increased in urine
73
what is the most common type of proteinuria AND the most serious clinically?
glomerular proteinuria
74
cause of renal proteinuria
gomerular or tubular proteinuria
75
postrenal proteinuria
inflammation in the urinary tract (normal kidney function, something after kidneys is introducing proteins)
76
conditions resulting in prerenal proteinuria
septicemia, hemoglobinuria, myoglobinuria, or multiple myeloma and macroglobulinemia
77
postural (orthostatic) proteinuria
type of functional proteinuria characterized by urinary excretion of proteins only when the individual is in an upright position
78
SSA precipitation test - to which reagent strip test does it relate to? what does a positive result look like?
Protein (ALL protein) - positive result is white/turbid, the more turbid the higher + value
79
What is the principle of protein reagent strip test?
the protein error of indicators
80
limitation of protein reagent strip test
only detects albumin; does not detect other proteins
81
What reagent strip test does Sensitive Albumin Tests relate to?
Protein - tests for small amounts of albumin <2.0 mg/dL that strip test may not detect.
82
hematuria
abnormal amount of RBCs in urine (cloudy sample)
83
hemoglobinuria
presence of hemoglobin in the urine (clear sample)
84
myoglobinuria
muscle damage that causes release of myoglobin in the blood
85
hemosiderin
a storage form of iron
86
principle of the blood reagent strip test
pseudoperoxidase activity of the heme moiety
87
T/F: <2.0 mg/dL of albumin the urine is considered abnormal.
False. It is normal to have very small amounts of albumin in the urine.
88
What is the normal level of WBC in the urine?
10 WBC/uL
89
What does increased number of WBC/leukocyte esterase in the urine indicate?
inflammation
90
When are WBC susceptible to lysis in the urine?
hypotonic and alkaline urine
91
Limitations of leukocyte esterase reagent strip test
Does not detect lymphocytes
92
Principle of nitrite reagent strip test
formation of diazonium salt and an azo coupling reaction
93
What does nitrite in the urine indicate? Why?
Bacterial infection (UTI). Bacteria (such as E. coli) can reduce nitrate to nitrite.
94
Glucosuria
presence of glucose in the urine
95
Glycosuria
presence of non-glucose sugars in the urine
96
What is the renal threshold level of glucose? What happens if this is exceeded?
160-180 mg/dL. If it is exceeded, glucose will be excreted in the urine.
97
The most common disease that causes hyperglycemia and glucosuria
Diabetes mellitus
98
principle of glucose reagent strip test
double sequential enzyme reaction that detects only glucose
99
what is considered normal excretion of glucose in the urine?
<20 mg/dL
100
Clinitest - what is it? what reagent strip test does this relate to? What does a positive result look like?
Copper reduction test to look for any reducing sugar in the urine. Relates to glucose test but is less limiting. A positive result will be orange.
101
Normal amount of ketones in urine?
No ketones in urine should be present
102
What are the 3 types of ketones? Which is the most common found in serum/urine?
Acetoacetate
Beta-hydroxybutyrate (MOST COMMON)
Acetone
103
What is the first ketone formed by the liver cells?
Acetoacetate. It can form into acetone or beta-hydroxybutyrate (most common).
104
Which ketones are detected in testing?
Only acetoacetate or acetone. There are no methods of detection for beta-hydroxybutyrate.
105
Principle of the ketone reagent strip test
Nitroprusside reaction
106
What reagent strip test does Acetest relate to? What does a positive reaction look like?
Acetest detects ketones in the urine. A positive result is a purple color.
107
T/F: ANY amount of bilirubin in the urine is clinically significant
True
108
What is ascorbic acid? What reagent strip tests are vulnerable to ascorbic acid interference? Does it cause a false negative or a false positive for these tests?
Vitamin C.
| It may interfere with blood, bilirubin, glucose, and nitrite strip tests by causing a false NEGATIVE.
109
principle of bilirubin reagent strip test
coupling reaction of a diazonium salt to form an azo dye
110
Bilirubin vs urobilinogen
Bilirubin comes from breakdown of hemoglobin; Urobilinogen comes from breakdown of bilirubin
111
What reagent strip test does the icotest relate to? What does a positive result look like?
Bilirubin - must more sensitive than than reagent strip test. positive result will be a purple/bruise color
112
principle for urobilinogen strip test
Ehrlich's reaction or azo coupling reaction
113
Normal urobilinogen in urine
<1 mg/dL
114
What is the only component that is normal to find small amounts of in urine?
Urobilinogen
115
Sternheimer-Malbin stain
supravital stain (stains live parts of cells) consisiting of crystal violet and safranin
116
2% acetic acid for use in microscopy
can help ID WBC cause it lyses RBC
117
0.5% Toluidine blue stain
helps to distinguish cells of similar size
118
Sudan III stain or oil red O stain
Stains fats or lipids orange/red
119
Prussian Blue stain
helps to visualize hemosiderin (iron aggregates)
120
Hansel stain
used to ID eosinophils in urine
121
Most common type of microscopy
brightfield
122
What produces a maltese cross pattern with polarized light under a microscope?
Cholesterol
123
Normal reference range for RBC in urine microscopy
0-3 per HPF
124
Normal reference range for WBC in urine microscopy
0-8 per HPF
125
Normal reference range for casts in urine microscopy
0-2 hyaline casts per LPF
126
Normal reference range for squamous/transitional/renal cells in urine microscopy
squamous: few per LPF
| transitional/renal: few per HPF
127
Normal reference range for bacteria and yeast in urine microscopy
none
128
Normal reference range for abnormal crystals in urine microscopy
none
129
What does eosinophiluria indicate?
acute interstitial nephritis (AIN)
130
Oval fat bodies
monocyte/macrophage that ingested lipoproteins and fat
131
Presence of many renal tubular epithelial cells indicates what?
intrinsic renal disease
132
What are casts made of?
uromodulin AKA Tam-Horsfall protein
133
What promotes disintegration of casts?
Hypotonic and alkaline urine
134
What enhances cast formation?
acidic urine, increased solute concentration (hypertonic), urine stasis, and increased plasma proteins
135
most clinically significant crystals are found in ______ urine.
acidic
136
Crystals ending in what are typically found in acidic urine?
"Urate"
137
Where are amorphous urates commonly found? Are they normal?
In "brick dust" samples caused by uroerythrin deposits. Yes they are normal.
138
What crystal is a small ball or sphere and yellow-brown?
acid urates
139
What crystal is rhombic or diamond shape and ONLY found in acidic urine <5.7?
Uric acid
140
What crystal is envelope shaped in dihydrate form and dumbbell shaped in monohydrate form, and can be found in any pH of urine?
Calcium oxalate
141
Clinical significance of high levels of calcium oxalate in urine
ingestion of ethylene glycol (antifreeze)
142
What is the most frequently observed crystal in urine?
Calcium oxalate
143
What do crystals found in alkaline urine end with?
"Phosphate" + ammonium biurate
144
What crystal looks like grains of sand and is found in white or gray macroscopic precipitate?
Amorphous phosphate
145
What crystal looks like a coffin lid and can be associated with kidney stones?
Triple phosphate
146
What crystal is found in alkaline urine, indicates dehydration, and has a thorny apple appearance?
Ammonium biurate
147
What crystal can produce CO2 gas with acetic acid?
Calcium carbonate
148
What crystal of metabolic origin appears as fine needles and is yellow-brown in color?
Bilirubin
149
What metabolic crystal is hexagonal and can indicate hereditary cystinosis?
Cystine
150
What crystals are fine, hairlike delicate needles? Which are concentric circles/radial striations? What is the clinical significance of finding these?
Tyrosine and Leucine
| Found in patients that cannot metabolize certain amino acids
151
What crystal appears as having notched corners, that must be accompanied by evidence of lipiduria and proteinuria?
Cholesterol
152
What drug crystal can be found in the urine that looks like sheaves of wheat?
Sulfonamides
153
What can cause flat, elongated parallelogram shaped plates in urine?
Radiographic contrast media
154
What must be moving in order to report it out?
Trichomonads
155
What stain is used to identify hemosiderin?
Prussian blue stain
