Urinalysis

Question 1

What are the types of analysis?

Answer 1

Types of Analysis

1. Macroscopic Examination
2. Chemical Analysis (Urine Dipstick)
3. Microscopic Examination
4. Culture (not covered in this lecture)

Question 2

Components of macroscopic examination

Answer 2

Macroscopic Examination

1. Odor/Smell
2. Color

Question 3

If odor is ammonia-like what does that potentially indicate?

Answer 3

Ammonia-like: (Urea-splitting bacteria)

Question 4

If odor is foul, offensive what does that potentially indicate?

Answer 4

Foul, offensive: Old specimen, pus or inflammation

Question 5

If odor is sweet what does that potentially indicate?

Answer 5

Sweet: Glucose

Question 6

If odor is fruity what does that potentially indicate?

Answer 6

Fruity= Ketones

Question 7

If odor is sulfur what does that potentially indicate?

Answer 7

Sulfer= Asparagus

Question 8

If color is colorless what does potentially that indicate?

Answer 8

Colorless= Diluted urine

Question 9

If color is deep yellow what does potentially that indicate?

Answer 9

Deep Yellow= Concentrated Urine

Question 10

If color is yellow-green what does that potentially indicate?

Answer 10

Yellow-Green= Bilirubin / Biliverdin

Question 11

If color is red what does that potentially indicate?

Answer 11

Red= Blood / Hemoglobin

Question 12

What does a chemical analysis consist of?

Answer 12

Urine Dipstick

Question 13

What is the range for normal specific gavity?

Answer 13

Normal range of specific gravity: 1.001-1.030

Question 14

What is the cause of low specfic gravity (< 1.001)?

Answer 14

Diabetes insipidus (low SG)

Question 15

What is the cause of high specific gravity (> 1.030)?

Answer 15

Dehydration (high SG)

Question 16

What are some limitations of the urine dipstick?

Answer 16

Limitations of Urine Dipstick Specific Gravity

• Interference: alkaline urine
• Does not measure non-ionized solutes (e.g. glucose)

Question 17

What is the normal pH for urine?

Answer 17

Normal pH 6

Question 18

What causes urine to be acidic?

Answer 18

Acidic (less than 4.5):

• metabolic acidosis
• high-protein diet

Question 19

What would cause urine to be basic?

Answer 19

Alkaline (greater than 8.0)

• renal tubular acidosis (>5.5)

Question 20

What are the limitations of the urine dipstick for pH?

Answer 20

Limitations

• Interference: bacterial overgrowth (alkaline or acidic)
• “run over effect” effect of protein pad on pH indicator pad
  
  • Buffers from the protein area of the strip (pH 3.0) spill over to the pH area of the strip and make the pH of the sample appear more acidic than it really is.

Question 21

What are some pathological reasons for protein in the urine?

Answer 21

Pathological Reasons for Protein in Urine

• Glomerulonephritis
• Renal tumor

Question 22

What are some causes of glucose in the urine?

Answer 22

Glucose

• Diabetes mellitus
• Renal glycosuria

Question 23

What are some limitations of testing glucose on a urine dipstick?

Answer 23

Limitations

• Only measures glucose and not other sugars.
• Renal threshold must be passed in order for glucose to spill into the urine.

Question 24

What are the non-pathological reasons why protein would be in urine?

Answer 24

Non-Pathological Reasons for Protein in Urine

• Severe muscular exertion
• Pregnancy

Question 25

What are some causes of ketones in the urine?

Answer 25

Causes * Diabetic ketoacidosis * Prolonged fasting

Question 26

What are the limitations of testing for ketones in urine with a urine dipstick?

Answer 26

Limitations * Interference: expired reagents (degradation with exposure to moisture in air)

Question 27

What are some causes for blood in the urine?

Answer 27

Causes * Hematuria (nephritis, trauma, etc) * Hemoglobinuria (hemolysis, etc) * Myoglobinuria (rhabdomyolysis, etc)

Question 28

What is the cause for nitrite in the urine?

Answer 28

Cause * Gram negative bacteriuria

Question 29

What are some causes for bilirubin in the urine?

Answer 29

Causes * Increased direct bilirubin (correlates with urobilinogen and serum bilirubin) * Bile or Hepatic obstructions

Question 30

What are some causes for leukocyte esterase in the urine?

Answer 30

Causes * Pyuria * Acute inflammation * Renal calculus

Question 31

What are some key guidelines for urine preservation for the microscopic examination?

Answer 31

Preservation * Cells and casts begin to disintegrate in 1 - 3 hrs. at room temp. * Refrigeration for up to 48 hours (little loss of cells).

Question 32

What are some general aspects for specimen concentration for microscopic examination?

Answer 32

Specimen concentration * Ten to twenty-fold concentration by centrifugation.

Question 33

What does the presence of erythrocyte casts indicate?

Answer 33

Erythrocyte Casts: Glomerular diseases

Question 34

What does the presence of leukocyte casts indicate?

Answer 34

Leukocyte Casts: Pyuria, glomerular disease

Question 35

What is the Significance of Cellular Casts?

Answer 35

Question 36

What is a renal calcului?

Answer 36

Renal calcului = kidney stone

Question 37

What is the diagnosis?

Answer 37

* Diluted urine, request a voided urine in the morning * If persisting low SG, possible diabetes insipida * A microscopic may give negative results

Question 38

What is the diagnosis?

Answer 38

* Possible gallbladder or hepatic disease. * No hemolytic anemia. Perform bilirubins in serum * Microscopic unlikely to provide additional info

Question 39

What is the diagnosis?

Answer 39

* Possible UTI, request culture and antibiotic sensitivity * Negative Nitrite test: Gram positive bacteria * Lower SG may show less number of cells and bacteria * Un-common diagnosis in this type of patient

Question 40

What is the diagnosis?

Answer 40

* Diabetes Mellitus * May be decompensated and with ketoacidosis * Ketones should become negative after treatment

Question 41

What is the diagnosis?

Answer 41

* Glomerulonephritis * RBC casts reveals renal cortex involvement * RBC cast are not always present in GN

Question 42

What is the diagnosis?

Answer 42

**Acute pyelonephritis**

Question 43

What is the diagnosis?

Answer 43

**Diabetes mellitus, type I**

Question 44

What is the diagnosis?

Answer 44

**Nephrotic syndrome**

Question 45

What is the diagnosis?

Answer 45

**Renal calculus**

Question 46

What is the diagnosis?

Answer 46

**Systemic lupus erythematosus (SLE) with lupus nephritis**

Question 47

What is the diagnosis?

Answer 47

**Rhabdomyolysis**

Question 48

What is the diagnosis?

Answer 48

**Adult polycystic kidney disease with chronic renal failure**

Question 49

What is the diagnosis?

Answer 49

**Transitional cell carcinoma of bladder**

Question 50

What is the diagnosis?

Answer 50

**Factitious specimen**