Urinalysis

Question 1

What is used to analyze sediment in urine? The supernatant?

Answer 1

sed = light microscopy
sup = dipstick

Question 2

Wy is the urine centrifuged?

Answer 2

to produce supernatant and urinary pellet

Question 3

Specific gravity is determined by:

Answer 3

number and weight of solutes

Question 4

Osmolality is determined by:

Answer 4

ONLY the number of solutes

Question 5

Specific gravity is NOT a marker of how concentrated a sample is when:

Answer 5

abnormal numbers of heavy solutes are present in urine (e.g. contrast dye)

Question 6

What are the specific gravity and osmolality of a maximum dilute urine sample?

Answer 6

1.002

50-100 mOsm/kg

Question 7

In metabolic acidosis, urine pH is less than:

Answer 7

5.3

Question 8

Urine pH >7.5-8.0, suggests:

Answer 8

UTI with urea splitting bacteria (such as proteus)

Question 9

How does hyperglycemia cause glycosuria?

Answer 9

increases filtered load to greater than the reabsorptive capacity of proximal tubule

Question 10

What does glycosuria in the presence of normal blood glucose (renal glycosuria) imply?

Answer 10

PT dysfunction

Question 11

When are ketones often present?

Answer 11

fasting, DKA, and AKA

Question 12

How do increased plasma ketoanions lead to ketonuria? How is ketonuria diagnosed?

Answer 12

filtered load exceeding proximal tubular reabsorptive capacity

Dipstick specific for acetone and acetoacetate

Question 13

Elevated levels of plasma conjugated bilirubin lead to:

Answer 13

urinary excretion

Question 14

_______ bilirubin is water soluble, which ______ bilirubin is insoluble.

Answer 14

Conjugated

Unconjugated

Question 15

Which type of bilirubin will NOT be present in urine?

Answer 15

unconjugated– non water sol

Question 16

Nitrite is (present/absent) in normal urine.

Answer 16

absent

Question 17

Positive nitrite suggests:

Answer 17

UTI with nitrate reducing bacteria
(gram negative)

*Gram negative bacteria = most common uropathogens

Question 18

What is leukocyte esterase and how is it measured in urine?

Answer 18

Produced by neutroohils, and positive, when there are increased numbers of neutrophils in the urine

Dipstick (detects a neutrophil-specific leukocyte esterase)

Question 19

What is normal excretion of protein?

Answer 19

<150 mg/day

Question 20

What is Glomerular Proteinuria associated with?

Answer 20

increased permeability for protein in the glomerular capillary wall
(especially albumin)

Question 21

What test detects all protein in the urine?

Answer 21

Sulfosalicylic acid test

Question 22

How and where are low molecular proteins filtered and normally reabsorbed? What if they are not reabsorbed?

Answer 22

pinocytosis
proximal tubule

proximal tubular dysfunction

Question 23

What is overflow proteinuria? What will you see via urine dipstick?

Answer 23

1. Excess production of low molecular weight proteins
2. increased filtered load exceeds reabsorptive capacity of PT

dipstick test:
positive for sulfosalicylic acid
negative for albumin

Question 24

What is a “spot” urine sample?

Answer 24

ratio of urine protein over creatinine (both measured as mg/dl) in a “spot” urine sample

**reliable estimate of quantitative proteinuria

Question 25

Urine dipstick is normally (positive/negative) for blood.

Answer 25

negative

Question 26

Most common cause of positive dipstick for blood is:

Answer 26

presence of rbc’s in urinary sediment

Question 27

Dipstick tests are sensitive to:

Answer 27

free hemoglobin and myoglobin | RBC

Question 28

What are 5 characteristics of renal hematuria?

Answer 28

1. Dipstick positive 2. RBC’s in sediment, some dysmorphic 3. RBC casts 4. Absence of clots 5. Often associated with proteinuria

Question 29

What are 3 characteristics of non-renal hematuria that are different from renal hematuria?

Answer 29

1 .no RBC cats 2. no proteinuria 3. no abn shaped RBCs

Question 30

Describe urinary WBC's:

Answer 30

Granular cytoplasm irregular nucleus “glitter cells” (in polarized light?)

Question 31

What conditions will you see urinary WBC's in?

Answer 31

1. UTI 2. pyelonephritis 3. allergic interstitial nephritis 4. intense glomerulonephritis

Question 32

Urinary casts represent precipitates of:

Answer 32

protein forming in the lumen of tubules

Question 33

Where is Tamm-Horsfall protein formed, and what does it do?

Answer 33

by thick ascending limb of Henle cells forms the matrix of all casts

Question 34

What are the only normal casts? | What type of cast contains cellular debris?

Answer 34

hyaline granular

Question 35

Lipiduria is (present/absent) in normal urine.

Answer 35

absent

Question 36

What is lipiduria associated with? What causes it?

Answer 36

heavy proteinuria (nephrotic syndrome presence of lipoproteins

Question 37

What features of lipiduria may be noted using polarizing light?

Answer 37

Maltese crosses oval fat bodies fatty casts