URINALYSIS TUTORIAL

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OBJECTIVES:

At the end of this tutorial, and after studying the urinalysis handout, the student should be able to:

1. Describe how to properly collect, store, and test a urine sample.
2. List the types of urine collection procedures.
3. Describe what urine specific gravity is and what affects it.
4. Describe the significance and interpretation of urine dipstick reagent strip reactions for the following: pH, protein, glucose, ketones, bilirubin, blood, urobilinogen, nitrite, leukocyte esterase.
5. Describe how red blood cells, white blood cells, squamous cells, transitional cells, and tubular epithelial cells get into urine and what their significance is.
6. Describe how urinary casts are formed and list the types of casts.
7. Describe the significance of yeast, bacteria, and crystals in urinary sediment.
8. Correlate urinalysis findings with the clinical history.
9. Determine what additional clinical procedures should be done upon finding an abnormal result.

CASE 1

History:

This specimen was from a 14 year old boy whose mother brought him to their family physician because he had a fever of 40.6o C and shaking chills for the previous day. On physical examination, he had mild right costovertebral angle tenderness.

Macroscopic Urinalysis:

Color                 Yellow
Appearance            Turbid
Specific Gravity      1.017
pH                    6.5
Protein               Neg
Glucose               Neg
Ketones               1+
Bilirubin             Neg
Blood                 Neg
Urobilinogen          Neg
Nitrite               Neg
Leukocyte Esterase    4+

Microscopic Urinalysis:

WBC/hpf      >50/hpf
RBC/hpf      5-10/hpf
Casts        Many WBC
Other        Occasional transitional cells

Questions:

1. How do you explain the appearance of the urine? How do you relate this to other findings?
2. What is the significance of the finding on physical examination?
3. Is there a relation between the color of the urine and the diagnosis?
4. What findings on microscopic urinalysis would be of help?
5. What is the suspected diagnosis?
6. What else should you do?

CASE 2

History:

This specimen is from a 23 year old female who noted an increase in appetite and thirst over the past six months, although she had gained only 5 pounds. The patient also had complaints of polyuria, but there was no associated dysuria. A midstream clean catch urine was obtained.

Macroscopic Urinalysis:

Color                 Yellow
Appearance            Clear
Specific Gravity      1.008
pH                    5.5
Protein               Neg
Glucose               4+
Ketones               4+
Bilirubin             Neg
Blood                 Neg
Urobilinogen          Neg
Nitrite               Neg
Leukocyte Esterase    Neg

Microscopic Urinalysis:

WBC/hpf      None
RBC/hpf      1-2/hpf cells
Casts        None
Other        None

Questions:

1. What disease is suggested by these findings?
2. Will all sugars be detected by the reagent test strip for glucose? Why?
3. What is the significance of the positive test for ketones? What would you suspect if the ketones were positive and everything else was normal?
4. What other laboratory tests should be done in this patient?
5. What are some complications of her disease that can affect the urinary tract?

CASE 3

History:

This 5 year old boy usually drove his mother crazy by running around the house, but he had seemed lethargic for several weeks. His mother also noted some puffiness around his eyes.

Macroscopic Urinalysis:

Color                 Yellow
Appearance            Cloudy			
Specific Gravity      1.020			
pH                    6.0			
Protein               4+			
Glucose               Neg			
Ketones               Neg
Bilirubin             Neg
Blood                 Neg
Urobilinogen          Neg
Nitrite               Neg
Leukocyte Esterase    Neg

Microscopic Urinalysis:

WBC/hpf      1-2/hpf
RBC/hpf      None
Casts        None
Other        Occasional oval fat bodies

Questions:

1. What abnormal finding is present? Just what does the dipstick measure here, and what other test could be done on the urine?
2. What is suggested by the child's physical findings?
3. What other laboratory test(s) would be useful?
4. What is the diagnosis?

CASE 4

History:

This 45 year old male came to his doctor after spending a second sleepless night with excruciating lower abdominal pain. The pain seemed to come in waves and was unrelieved by aspirin, tylenol, a six-pack of beer, or lying or standing in any position. He had not experienced any similar pain before.

Macroscopic Urinalysis:

Color                     Dark Yellow
Appearance                Cloudy
Specific Gravity          1.015
pH                        6.0
Protein                   Neg
Glucose                   Neg
Ketones                   Neg
Bilirubin                 Neg
Blood                     3+
Urobilinogen              Neg
Nitrite                   Neg
Leukocyte Esterase        Neg

Microscopic Urinalysis:

WBC/hpf      2-5/hpf
RBC/hpf      >100/hpf
Casts        None
Other        Occasional squamous epithelial cells

Questions:

1. What abnormal findings are present?
2. What is the differential diagnosis?
3. What diagnosis do you suspect?
4. What other studies could be done?

CASE 5

History:

This urine specimen is from a 22 year old Black female who was admitted to hospital because of swelling of the legs and a weight gain of 9 kg (20 lbs) over the past week. She feels extremely tired. A chest radiograph shows marked pleural effusions.

Macroscopic Urinalysis:

Color                     Yellow
Appearance                Cloudy
Specific Gravity          1.020
pH                        6.0
Protein                   3+
Glucose                   Neg
Ketones                   Neg
Bilirubin                 Neg
Blood                     2+
Urobilinogen              Neg
Nitrite                   Neg
Leukocyte Esterase        Neg

Microscopic Urinalysis:

WBC/hpf      <5/hpf
RBC/hpf      5-10/hpf cells
Casts        Many hyaline, WBC, RBC, granular casts
Other        Mucus, renal tubular cells

Questions:

1. What is suggested by these findings?
2. What are possible underlying disease processes?
3. What additional laboratory tests would be helpful?

CASE 6

History:

Two construction workers managed to dislodge a large boulder from the path of a new water pipe installation. As the boulder began rolling, they suddenly became aware of a pickup truck parked below them at the bottom of the hill. The boulder smashed through the side window and landed on the driver's lap. That evening in hospital, the injured man's urine output began to drop.

Macroscopic Urinalysis:

Color                     Yellow-Brown
Appearance                Slightly cloudy
Specific Gravity          1.024
pH                        7.0
Protein                   Trace	
Glucose                   Neg			
Ketones                   Neg
Bilirubin                 Neg
Blood x                   4+
Urobilinogen              Neg
Nitrite                   Neg
Leukocyte Esterase        Neg

Microscopic Urinalysis:

WBC/hpf      Rare (<2/hpf)
RBC/hpf      Rare (0-1/hpf)
Casts        Occ hyaline, granular casts
Other        Squamous and renal tubular epithelial cells

Questions:

1. How do you explain the macroscopic findings in view of the microscopic findings? How does the history fit with this?
2. What further laboratory studies would be of help?
3. Explain the appearance of the casts and epithelial cells.
4. What are some other causes for this condition?

CASE 7

History:

A 48 year old male has polyuria, nocturia, and mild flank pain. His blood pressure is 155/90. Family history reveals that his father died in his early 50's of "kidney" disease. An intravenous pyelogram (IVP) done elsewhere showed no hydronephrosis or filling defects, but his kidneys were markedly enlarged.

Macroscopic Urinalysis:

Color                     Yellow
Appearance                Slightly cloudy
Specific Gravity          1.010
pH                        6.0
Protein                   1+
Glucose                   Neg
Ketones                   Neg
Bilirubin                 Neg
Blood                     1+
Urobilinogen              Neg
Nitrite                   Neg
Leukocyte Esterase        Neg

Microscopic Urinalysis:

WBC/hpf      Rare (<2/hpf)
RBC/hpf      5-10/hpf)
Casts        None
Other        Many oxalate crystals

Questions:

1. What do the historical findings suggest?
2. What laboratory tests would be useful?
3. If you were to give the patient anti-diuretic hormone (ADH) or if he didn't drink any water for 12 hours, and then the urinalysis was repeated and the specific gravity was still 1.010, what would this suggest?
4. Why do you think the kidneys are enlarged?

CASE 8

History:

A 57 year old male had a routine urinalysis as part of his company's yearly required physical examination. He has a chronic cough (50 pack/year smoking history). His only complaints referable to the urinary tract are some mild dysuria and hesitancy, but he otherwise feels fine.

Macroscopic Urinalysis:

Color                     Amber
Appearance                Hazy
Specific Gravity          1.018
pH                        5.0
Protein                   Trace
Glucose                   Neg
Ketones                   Neg
Bilirubin                 Neg
Blood                     2+
Urobilinogen              Neg
Nitrite                   Neg
Leukocyte Esterase        Neg

Microscopic Urinalysis:

WBC/hpf      Rare (<2/hpf)
RBC/hpf      10-30/hpf
Casts        Occasional hyaline casts
Other        Atypical urothelial cells present

Questions:

1. What do these findings suggest?
2. What further studies are indicated?
3. What social or environmental history would be important?

CASE 9

History:

A 39 year old woman comes to you complaining of lower abdominal pain. She left her job as a nurse's aide (her second day on the job) because the pain was so bad. She says the pain began after she had fallen off a stepstool while getting a bedpan off a top shelf. No one saw her fall, but she convinced her supervisor that she had an industrial accident and needed medical attention because of blood in her urine. To prove it, she brings in a urine specimen.

Macroscopic Urinalysis:

Color                     Red
Appearance                Clear
Specific Gravity          1.015
pH                        7.0
Protein                   Neg
Glucose                   Neg
Ketones                   Neg
Bilirubin                 Neg
Blood                     Neg
Urobilinogen              Neg
Nitrite                   Neg
Leukocyte Esterase        Neg

Microscopic Urinalysis:

WBC/hpf      Rare (<2/hpf)
RBC/hpf      None
Casts        Occasional hyaline casts
Other        Few squamous epithelial cells

Questions:

1. How do you correlate the macroscopic and microscopic findings?
2. What do you think is going on here?

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