Urinalysis Flashcards
(99 cards)
1
Q
when do you do microscope exams on urine?
A
When levels of blood, leukocytes and/or proteins are greater than trace.
2
Q
How do you start a microscopic examination of urine?
A
Centrifuging the sample
3
Q
What’s the ideal volume for an urine examination?
A
8-12mL
4
Q
What do you do with the supernatant of centrifuged urine?
A
You pour it away till there’s ~1mL left.
5
Q
How many RBC/HPF is considered normal in some urine samples?
A
3-5 RBC
6
Q
What’s HPF?
A
High powered field; 40x
7
Q
What’s LPF?
A
Low powered field; 10x
8
Q
What do you look for on LPF?
A
Casts
9
Q
What do you look for under HPF?
A
Cells and other elements (ex. Epidermis cells)
10
Q
How many fields are examined to find an average number of cells and elements?
A
10 fields
11
Q
What is hematuria?
A
An increased # of RBC in urine
12
Q
An increased # of red cells with red blood cell casts = ?
A
Source of hematuria is most likely renal.
13
Q
An increase in red cells without red blood cell casts = ?
A
Source of hematuria is somewhere in the urinary tract but not the kidney
14
Q
What affects the morphology of red cells?
A
specific gravity (SG) and the pH
15
Q
What happens to RBC when the sg is high?
A
RBC will appear shrunken or crenated
16
Q
What happens to the RBC when the specific gravity is low?
A
RBCs will be swollen or rapidly break apart
17
Q
What happens to the RBC when the pH is very alkaline (basic)?
A
RBCs will be swollen or rapidly break apart
18
Q
How do you confirm that there is RBC in urine?
A
The blood portion of a dipstick should indicate that there’s 6-10/HPF
19
Q
What is considered a normal amount of leukocytes in urine?
A
6-10/HPF
20
Q
Leukocytes are more predominant in urine samples of men. (T/F)
A
False
21
Q
What is pyuria?
A
It is the increased number of leukocytes in urine
22
Q
How can you identify a neutrophil?
A
The multi-lobed nucleus
23
Q
What can be viewed in urine samples of those who just finished a strenuous exercise or are stressed?
A
Slight pyuria and proteinuria
24
Q
What does pyuria usually indicate?
A
Inflammatory process in or adjacent to the urinary tract
25
Large numbers of leukocytes in clumps indicates?
Acute infection of the urinary tract
26
What does large numbers of leukocytes and clumps as well as minimal proteinuria and leukocyte casts indicate?
Pyelonephritis
27
What does large numbers of leukocytes and clumps as well as minimal proteinuria and with NO leukocyte casts indicate?
Lower UTI
28
What is considered “heavy” pyuria?
>50/HPF
29
What happens to leukocytes when the urine is concentrated and acidic?
They shrink
30
What do RBCs usually get mixed up with?
Yeast, leukocytes and urate crystals
31
What happens to leukocytes when the urine is dilute or alkaline?
The cells swell up or rapidly lyse
32
What percentage do leukocytes decrease by within two hours of collection when urine is too alkaline and dilute, and not refrigerated?
~60%
33
What are glitter cells?
When the leukocytes are swelling and showing what is called Brownian movement of granules in the cytoplasm of the cells
34
How do you confirm leukocytes in the urine?
When the dipstick shows at least 10/HPF
35
What are the three types of epithelial cells in urine?
1. Renal tubular epithelial (RTE)
2. Transitional
3. Squamous
36
What does SG being low mean?
Urine is dilute
37
What does SG being high mean?
>1; the urine is very concentrated
38
Why do RBC/leukocytes swell when the SG is low?
The water from the urine is moving into the cells
39
Why do RBC/leukocytes shrink when SG is high?
The water from the cells are moving out into the urine.
40
where do squamous cells originate from?
Tubules of the nephrons
41
Where do transitional cells originate?
Renal pelvis, ureters, urinary bladder and two-thirds of the urethra
42
Where do squamous cells originate from?
Terminal end of urethra and vagina
43
What types of epithelial cells would you find in healthy individuals?
Renal tubular epi cells and transitional epi cells
44
An increase in renal tubular epi cells and transitional epi cells indicate what?
Inflammation within kidney or lower urinary tract
45
What typically causes RTE to increase in numbers?
- agents like heavy metal that damage RTEs
- renal infections like pyelonephritis
- decrease blood supply to kidney
46
What causes the increase in transitional epithelial cells?
Early pyelonephritis, kidney stones, bladder infection or catheterization trauma
47
Is squamous epithelial cells indicative of anything?
Usually not; usually vaginal contamination
48
Where are casts formed?
In the lumen of the distal convoluted tubule (DCT) or the collecting duct (CT)
49
What are casts?
Cylindrical mold of the tubular lumen
50
What is the matrix of casts usually composed of?
Uromodulin; Tamm-Horsfall protein (THP)
51
What type of cells synthesizes uromodulin?
Renal tubular epithelial cells
52
What is the renal tubular section of the urinary tract system?
It is the fat portion of the ascending loop of Henle and the DCT
53
Is uromodulin found in plasma?
No
54
How do you determine if a renal disease is in its late stages?
Casts have large diameters due to the enlargement of renal tubules
55
What are broad casts and chronic renal failure casts?
Casts that are 2-6 times wider than ordinary casts
56
What are the classification of casts?
Hyaline, red blood cell, leukocyte, epithelial, granular, waxy and fatty
57
What characteristics do hyaline casts have?
They’re colourless and transparent
58
What kind of casts are most commonly seen in urine samples?
Hyaline casts
59
What are RBC casts commonly associated with?
Glomerulonephritis
60
What’s the difference between RBC casts and hemoglobin casts?
Hemoglobin casts contain disintegrated and lysed RBC
61
What is the most common wbc found in leukocyte casts?
Neutrophil
62
What are granular casts?
When neutrophils disintegrate into granular debris.
63
What is the most common cause of leukocyte casts?
Renal infection; pyelonephritis
64
What type of epithelial cells are found in epithelial casts?
Renal tubular epithelial cells
65
What do epithelial casts indicate?
Tubular necrosis
66
What damages renal tubules?
- viruses
- nephrotoxic agents
- organ rejection after a kidney transplant
67
What’s the difference between coarse and fine granular casts?
Coarse granular casts are formed when cells disintegrated into granular debris.
Fine granular casts are by-products of RTE protein metabolism and binds to uromodulin. Also moser common
68
What does the presence of both fine and coarse granular casts indicate?
Significant renal diseases
69
What are waxy casts?
Opaque and paraffin-like with cracked/notched outlined casts that are late-stage of hyaline or granular casts
70
What do waxy casts indicate?
Long renal transit time; chronic renal disease, nephrotic syndrome or organ transplant rejection
71
What’s the difference between free fat and oval fat casts?
Free fat is globular and glistens. Whereas, oval fat bodies are RTEs that fat has accumulated
72
What kind of stain could be used for fat casts?
Sudan IV dye
73
What is commonly seen in urine for Nephrotic syndrome?
Massive proteinuria and fats
74
How are crystals formed?
When chemicals are present in the urine at an excess amount in comparison to their solubility.
75
What are examples of crystals found in acid urine?
- calcium oxalate
- uric acid
- amorphous urates
76
What are some examples of crystals found in alkaline urine?
- tripe phosphate
- amorphous phosphates
- calcium carbonate
- calcium phosphate
- calcium oxalate
77
What pH are abnormal crystals found in?
Acidic urine
78
What are some examples of abnormal crystals?
Cystine, leucine, tyrosine, cholesterol and bilirubin
79
What is a distinctive characteristic of amorphous urates?
Appear to be pink precipitate
80
What does a large amount of uric acid in urine indicate?
Gout
81
What are triple phosphate usually associated with?
Chronic UTI
82
What does cystine crystals usually mean?
The patient has cystinuria
83
What is cystinuria?
Inborn error of metabolism where cysteine is not reabsorbed
84
What’s the characteristic of cystine?
Hexagonal plates
85
What are some characteristics of leucine?
Yellow, spheres with radial striations
| Has a maple syrup odour
86
What does leucine crystals indicate?
Maple syrup disease = error in leucine metabolism
87
What are some characteristics of tyrosine?
They look like fine needles and often found with leucine crystals
88
What does tyrosine usually indicate?
Severe liver disease = cirrhosis or viral hepatitis
89
What do cholesterol crystals look like?
Plates with notched corners
90
What do cholesterol crystals indicate?
Nephrotic syndrome or severe UTI
91
What’s the difference between calcium phosphate and bilirubin crystals?
Calcium phosphate is found in alkaline urine while bilirubin is found in acidic urine.
CP has blunt ends and are colourless where bilirubin is delicate and pointy ended and red-brownish!
92
What suggests contamination when you see bacteria in urine?
Bacteria without leukocytes and increased amount of squamous cells
93
What do mucus threads look like?
Long ribbon-like strands with tapered ends
94
What amount of RBC found in urine is normal?
3-5/hpf
95
What amount of leukocytes are considered normal?
6-10/hpf
96
What amount of squamous epithelial cells is considered normal?
6-10
97
What gives urine its yellow/amber colour?
Pigment urochrome and urobilin
98
What is the minimum amount of urine for routine urinalysis?
8mL
99
What’s the average amount of urine collected for a 24-hr test?
1500mL/day
