Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Clinical Chemistry Practicum > Urinalysis > Flashcards

Urinalysis Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

What is the requirements for specimen collection of urine?

A
  • Dry, clean, leak-proof container
  • Minimum of 10-15 mL volume
  • First morning collection is best
  • Properly labeled with a requisition form
  • Tested within 2 hrs* or refrigerated for up to 8 hrs (allow to return to R.T. before testing)
  • No testing on a sample older than 4 hours (unless collected in BD preservative tube)
  • No microscopy performed on refrigerated samples
  • Chemical preservatives can interfere with some of the tests i.e.. Formalin interferes with glucose, blood, leukocyte esterase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How long do BD tubes keep sample integrity for?

A

For up to 72 hours without refrigeration for urine chemical and microscopic analysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What preservatives do BD tubes have?

A

A preservative of chlorhexidine, ethylparaben and sodium propionate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is used for microscope slide examination of urine?

A

Kova slide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the principle of measurement of the NOVAS?

A

Combines dry-pad technology with an easy-to-use cassette test format

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the principle of measurement of the ADVANTUS?

A
  • Dry chemistry reagent strips
  • Color change measured by reflectance photometry
  • Dual readings at reactive and reference wavelengths
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does time collection of urine affect pH?

A

It is more acidic in AM, more alkaline after meals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens if the pH of a sample is greater than 8?

A

Can assume the sample is old

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens if the urine test pad lingers too long in the sample or is not blotted properly?

A

The acid buffer from the protein pad can contaminate the pH pad and cause a falsely low reading- as test pad is strongly buffered at pH of 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why would we look at pH in a urine sample?

A

Helps determine the type of crystals present in the sample (i.e. uric acid crystals will only be present if the pH is acidic).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What factors contribute to formation of casts in the kidney?

A
  • Larger than normal amounts of plasma proteins entering the tubules
  • Decreased pH
  • Decreased urinary flow rate (urinary stasis)
  • Increased urine concentration (increased specific gravity)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What conditions are hyaline casts seen in?

A
  • Glomerulonephritis
  • Strenuous exercise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do cellular casts consist of?

A
  • Cellular casts consist of a uromodulin mucoprotein matrix containing RBCs or WBCs, renal tubular epithelial cells, or a mixture of these cell types.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are cellular casts produced?

A

Distal tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where may white cell casts be seen?

A

They are associated with infection or inflammation of the nephron. WBC casts can be seen in cases of pyelonephritis and interstitial nephritis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does the presence of red cell casts mean?

A

The presence of red cell casts in the urine indicates bleeding into the nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What do RTE casts indicate?

A

These casts indicate tubular damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are granular casts composed of?

A

Cellular remnants and by-products of protein degradation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are waxy casts seen in?

A
  • Stasis of urine flow
  • Chronic renal failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are fatty casts indicative of?

A
  • Nephrotic syndrome
  • Toxic tubular necrosis
  • Diabetes mellitus
  • Crush injuries
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a UTI/CYSTIS infection?

A

An infection of the lower urinary system. Most involve bladder and urethra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a PYELONEPHRITIS infection?

A

It is an infection of the upper urinary system, can be acute or chronic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What can be seen in the urinalysis of acute polynephritis?

A

Mild proteinuria, positive nitrate, numerous WBCs, RBCs, bacteria; WBC and bacterial casts, transitional and RTE cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What can be seen in the urinalysis of chronic polynephritis?

A

Similar to acute pylonephritis. As disease progresses: renal concentration is decreased, increased proteinuria, hematuria; granular, waxy and broad casts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is an acute PYELONEPHRITIS infection?

A

Bacterial invasion of the renal parenchyma by ascending from the lower urinary tract due to incomplete bladder emptying which can be due to the bacterial invasion of the bloodstream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is Glomerulonephritis?

A

Sterile, inflammatory process in glomerulus and is associated with the finding of blood, protein, and casts in the urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What can be seen in the urinalysis of Glomerulonephritis?

A

Marked hematuria, proteinuria; RBC, hyaline and granular casts (broad casts in chronic glomerulonephritis), dysmorphic RBCs and WBCs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What can be seen in the urinalysis of nephrotic syndrome?

A

Marked proteinuria, urinary fat droplets, oval fat bodies, RTE; epithelial, hyaline,fatty and waxy casts; microscopic hematuria, may have cholesterol crystals

29
Q

What is nephrotic syndrome?

A

Non-specifickidney disorder with marked proteinuria, low levels of serum albumin and high serum lipids

30
Q

What causes falsely alkaline pH?

A

> 8 = improper storage (urease producing bacteria; urea- ammonia)

31
Q

What causes falsely acidic pH?

A

Prolonged dipping or not blotted properly

32
Q

What causes false positives for glucose?

A

Oxidizing agents or detergents

33
Q

What causes false negatives for glucose?

A
  • Improper storage (glycolysis by bacteria)
  • High ketone levels
  • High SG
  • Low temp
34
Q

What are false positives for ketones?

A
  • Drugs with sulfhydryl groups
  • Red pigments
35
Q

What are false negatives for ketones?

A

Improper storage –> evaporation or breakdown by bacteria

36
Q

What can an alkaline pH correlate with?

A

Urinary tract infection

37
Q

What can ketones correlate with?

A
  • Glucose with diabetes
  • May also be due to excess vomiting or starvation
38
Q

Can can Proteinuria correlate with?

A
  • RBC, WBC in urine
  • Nephrotic Syndrome
39
Q

What are false postives for protein?

A
  • Semen contamination
  • Prolonged dipping
  • Highly buffered alkaline urine
  • High SG
  • Pigmented specimens
40
Q

What are false negatives for protein?

A
  • Proteins present other than albumin
41
Q

What are false positives for bilirubin?

A

Pigments from certain drugs

42
Q

What are false negatives for bilirubin?

A
  • Improper storage (light exposure)
  • Ascorbic acid or nitrite in high concentrations (due to diazo reaction)
43
Q

What conditions are bilirubin be positive?

A

Post hepatic jaundice, bile duct obstruction, liver damage

44
Q

Why are bacterial casts clinically significant?

A
  • Pyelonephritis
45
Q

What conditions can RBC casts be seen in?

A
  • Glomerulonephritis
  • Strenuous exercise
46
Q

What condition do RTE cells suggest?

A

Renal tubular damage

47
Q

What are granular casts indicative of?

A
  • Glomerulonephritis
  • Pyelonephritis
  • Stress and exercise
48
Q

What are broad casts indicative of?

A
  • Extreme urine stasis
  • Renal failure
49
Q

What are false positives for urobilinogen?

A

Highly pigmented urine

50
Q

What are false negatives for urobilinogen?

A
  • Formalin as a preservation
  • High concentrations of ascorbic acid or nitrite (diazo interference)
51
Q

What does Nitrite screen for?

A

UTI

52
Q

What are false positives for nitrite?

A
  • Improper storage
  • Highly pigmented urines
53
Q

What are false negatives for nitrite?

A
  • When there is a UTI but this test is negative (see next slide)
  • Ascorbic acid (diazo)
  • High SG
54
Q

What are false positives for leukocytes?

A
  • Oxidizing agents
  • Contamination with vaginal discharge
  • Highly pigmented urines
  • Formalin
55
Q

What are false negatives for leukocytes?

A
  • High SG (WBC’s don’t lyse)
  • High concentration of Protein, Glucose, Ascorbic acid, and Oxalic Acid
  • WBC’s are lymphocytes, not neutrophils
  • Unmixed sample
  • Antibiotics
56
Q

What are false positives for blood?

A
  • Menstrual contamination
  • Myoglobin (Heme molecule)
  • Oxidizing agents or detergents (Bleach)
  • Bacterial peroxidases
57
Q

What are false negatives for blood?

A
  • High SG (cells won’t lyse on contact with the test pad)
  • Ascorbic acid (manufacturers correct for this)
  • Unmixed specimens
  • Formalin, captopril, nitrite
58
Q

What is specific gravity?

A

The ratio of the density of a substance to the density of a reference substance

59
Q

When are ammonium biurate crystals found?

A

Encountered in old specimens and may be associated with the presence of the ammonia produced by urea-splitting bacteria

60
Q

When are calcium oxalate crystals found?

A

Can be found in fresh urine or in people who consume foods rich in oxalic acid such as asparagus, tomatoes etc.

61
Q

When are uric acid crystals found?

A

Associated with increased levels of purines and nucleic acids and are seen in patients with leukemia who are receiving chemotherapy, and sometimes in patients with gout.

62
Q

When are calcium monhydrate crystals found?

A

Ethyl glycol poisoning (anti-freeze)

63
Q

When are triple phosphate crystals found?

A

No clinical significance; however, they are often seen in highly alkaline urine associated with the presence of urea- splitting bacteria.

64
Q

When are cystine crystals found?

A

In the urine of persons who inherit a metabolic disorder called cystinuria

65
Q

When are cholesterol crystals found?

A

Associated with disorders producing lipiduria, such as the nephrotic syndrome, and are seen in conjunction with fatty casts and oval fat bodies.

66
Q

When are bilirubin crystals found?

A

Present in hepatic disorders producing large amounts of bilirubin in the urine

67
Q

When are sulfonamide crystals found?

A
  • Inadequate patient hydration
  • Tubular damage if crystals are forming in the nephron.
68
Q

When are tyrosine crystals found?

A

Found in acidic urine, and they may be caused by metabolic disorders like liver disease

69
Q

When are leucine crystals found?

A

Usually symptom of severe liver disease

Clinical Chemistry Practicum (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions