Urinalysis Flashcards Preview

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Flashcards in Urinalysis Deck (62):
1

What does the urinalysis important for?

-Discovering disease in the urinary tract
-Estimate renal function
-Clues as to what causes renal dysfunction
-Some systemic diseases cause alterations in urine constituents

2

What is included in a standard urine panel?

-Appearance
-pH
-Specific gravity
-Protein
-Glucose
-Ketones
-Nitrites
-Leukocyte esterase
-Urobilinogen

3

When is appearance of urine reported? What is normal appearance?

When it is abnormal
-Should be pale, dark yellow, and clear

4

What does urine have in it if it is turbid

-Excessive cellular material or protein
-or from crystallization or precipitation of salts

5

When do salts precipitate?

When urine is basic (should be acidic)

6

If the specimen clears with the addition of small amounts of acid, what is the cause?

-Precipitation of salts

7

What can cause red or brown urine?

-Hemoglobin
-Myoglobin
-Fresh beets
-Pyridium (causes dark orange urine)

8

What acidifies glomerular filtrate of plasma

Renal tubules and collecting ducts from a pH of 7.4 to 5-6

9

When will you see a pH of 6 or more

-Alkalosis
-If the acidifying mechanism of the kidney fails

10

What happens to urine if it is left standing

-Become alkaline due to bacterial growth

11

What is directly proportional to urine osmolarity

Specific gravity

12

What does specific gravity measure

The ability of the kidney to dilute or concentrate the urine

13

What diseases cause the inability to concentrate the urine?

-Diabetes insipidus
-Severe hyperthyroidism

14

What prevents the majority amount of large materials to escape from the blood into the urine

Glomerular membrane

15

What is normal protein excretion

150mg/24 hours

16

What defines proteinuria

Protein excretion more than 150mg per day

17

What classifies severe proteinuria

more than 3.5mg/24 hours

18

What causes severe proteinuria

Nephrotic syndrome

19

+1 protein=

200-500 mg/24 hours

20

+2 protein=

500-1500 mg/24 hours

21

+3 protein=

1.5-5 g/24 hours

22

+4 protein=

greater than 5g/24

23

What is the dominant constituent in proteinuria and why?

-Albumin
-Because it is the smallest

24

What abnormal protein usually appears in the urine in patients with multiple myeloma

Bence jones proteins

25

What are the 2 types of proteinuria

1. Functional
-not associated with systemic or renal disease
2. Organic
-associated with systemic disease or renal pathology

26

What are examples of functional proteinuria

-Severe muscular exertion
-Pregnancy

27

What are examples of organic proteinuria

-Pre-renal
-Renal
-Postrenal

28

Describe pre-renal organic proteinuria

-Not due to renal disease
-Problem occurs before reaching the kidney
-Fever
-Sepsis
-Hypertension
-Bence Jones proteins

29

Describe renal organic proteinuria

-Primary kidney disease
-Glomerulonephritis
-Nephrotic syndrome

30

Describe post-renal organic proteinuria

-Protein is added to the urine farther down the urinary tract
-Infection of the ureter
-Cystic
-Urethritis/prostatitis
-Contamination with vaginal secretions

31

What is commonly seen in urine contamination with vaginal secretions

High number of squamous epithelial cells

32

What is the most common cause of glucosuria

Diabetes mellitis

33

What is the normal renal threshold for glucose before it starts spilling over into the urine

180 mg/dl

34

T/F- Individuals can vary in their tubular transfer reabsorptive capacities

True

35

If reabsorptive capacity is low, the patient will spill glucose at (higher/lower) levels
-what causes this

Lower
-Pregnancy and the exposure to carbon monoxide and lead cause it

36

What are examples of ketones

-Acetone
-Acetoacetic acid
-Beta-hydroxyl butyric acid

37

What is the major cause of increased ketones

-Carbohydrate restriction
-impaired carbohydrate metabolism

38

What muscle types can utilize a limited amount of ketones as an energy source when glucose is insufficient

-Skeletal
-Cardiac

39

T/F- After a certain point, metabolic capacity is exceeded and excess ketone bodies are excreted by the kidney

True

40

Ketosis is...

When ketones accumulate in the plasma

41

Many bacteria produce an enzyme called...

reductase

42

What does reductase do?

Converts nitrates to nitrites

43

A positive nitrite test indicates that...

bacteria may be present in the urine

44

What is the sensitivity of the nitrite test

50%

45

What is the gold standard test for urine

Urine culture

46

T/F-The nitrite test can enhance the sensitivity of the leukocyte esterase test to detect urinary tract infections

True

47

This is an enzyme found in the cytoplasm of neutrophils

Esterase

48

When is a positive leukocyte esterase test seen?

-When there are WBC as whole or lysed cells in the urine

49

What does positive leukocyte esterase indicate?

Pyuria

50

How sensitive is leukocyte esterase test in detecting urinary tract infections

80-90% sensitive

51

Can leukocyte esterase differentiate between WBC from the urinary tract or vaginal secretions?

Nope

52

What is produced from the conjugated bilirubin by metabolic activity of bacteria in the intestine followed by reabsorption into the blood steam

Urobiliogen

53

When can conjugated bilirubin be seen?

Secondary to biliary tract obstructions

54

Extrahepatic =

Common bile duct obstruction

55

Intrahepatic=

Liver cell injury (cirrhosis or hepatitis)

56

When is a microscopic analysis of urine completed

After the urine has been centrifuged

57

What is the presence of RBC in the urine called

Hematuria

58

What are causes of hematuria

-Glomerular damage
-Tumors
-Kidney trauma
-Nephrolithiasis
-Urinary tract infections

59

When can contamination with RBC occur

During menses or catheriziation (especially if you have prostate problems)

60

How can RBC look

-Normal shape
-Swollen (dilute urine)
-Crenated (concentrated urine)

61

When are squamous epithelial cells typically seen

Contamination with normal skin flora

62

These are protein conglomerates that outline the shape of the renal tubules in which they were formed

Protein casts