Introduction to Clinical Microscopy

5th Century BCE

Hippocrates was able to write a book for Uroscopy

1140 CE

Color charts were developed that described 20 different colors of urine

1694

Frederik Dekker's discovery of albuminuria by boiling the urine sample

17th Century

Invention of the Microscope, which allowed Thomas Addis to examine urine sediment under the microscope

1827

Richard Bright introduced Urinalysis as part of routine patient examination

1. Readily available

2. Easily collected

3. Contains info about many of the body’s major metabolic functions

What are the unique characteristics of a urine specimen?

To aid in the diagnosis of the disease, screens asymptomatic populations for undetected disorders, congenital or hereditary diseases, monitor the progress of disease, and monitor the effectiveness of therapy or complications.

What is the purpose of urinalysis?

1200mL

What is the average daily urine output?

• 95% water

• 5% solute

Urine is composed of?

• Urea

• Creatinine

• Uric acid

• Hippuric acid

What are the organic solutes in the urine?

• Sodium chloride

• Potassium

• Sulfate

• Phosphate

• Ammonium

• Magnesium

• Calcium

What are the Inorganic solutes in the urine?

0.1%

How many percent is Sodium and Creatinine in the urine?

0.05%

How many percent is Ammonia in the urine?

0.18%

How many percent is Sulphate e in the urine?

0.12%

How many percent is Phosphate in the urine?

0.6%

How many percent is Chloride in the urine?

0.01%

How many percent is Magnesium in the urine?

0.015%

How many percent is calcium in the urine?

0.6%

How many percent is Potassium in the urine?

0.03%

How many percent is uric acid in the urine?

2%

How many percent is urea in the urine?

• Urea

• Creatinine

• Uric acid

• Chloride

What are the primary components in normal urine?

Urea

• primary organic component

• Product of protein and amino acid metabolism

Creatinine

Product of creatinine metabolism by muscles

Uric acid

Product of nucleic acid breakdown in food and cells

Chloride

• Primary inorganic component

• Found in combination with sodium

1. Dietary Intake

2. Body Metabolism

3. Physical Activity

4. Endocrine Functions

5. Body Positions

Factors that influence variations in the concentration of the solutes:

Oliguria

• the decrease in urine output.

• The body enters a state of dehydration

• There is excessive water loss that is maybe from vomiting, diarrhea, perspiration, or severe burns.

• Results in a decrease of the urine output

less than 0.5mL per kilogram per hour

Oliguria in children

less than 400mL per day

Oliguria in adults

Anuria

• the cessation of urine flow.

• Resulting from serious damage to the kidneys, or there is decrease of the blood flow to the kidneys.

Nocturia

• the increase in nocturnal excretion of urine.

• a patient tends to urinate excessively during the night rather than the day.

Polyuria

• the increase in daily urine volume.

• Associated with diabetes mellitus and diabetes insipidus

• This can also be artificially induced by diuretics, the intake of caffeine, or alcohol.

Greater than 2.5L per day

Polyuria in adults

2.5 to 3mL/kg per day

Polyuria in children

Diabetes mellitus

• There is a defect in pancreatic production of insulin or in the function of insulin itself.

• Both of these defects result in the body’s increase in glucose formation

• The resulting urine appears diluted, with a high specific gravity because of increased glucose content.

Diabetes insipidus

• Decrease production or function of the hormone ADH (antidiuretic hormone).

• Water is not reabsorbed from the plasma filtrate.

• The water needed for adequate body hydration is not reabsorbed but instead excreted.

• The urine of patients is truly dilute and with a low specific gravity.

1. First Morning Specimen

2. Random Specimen

3. Time Collection: 24-Hour Specimen

4. Fasting Specimen

5. Two-Hour Post Prandial Specimen

6. Glucose Tolerance Specimens

7. Prostatic Specimen

Types of urine specimen accepted in the laboratory:

First morning specimen

• This is collected immediately on arising from sleep.

• This is the urine that is retained in the bladder for approximately 8 hours.

• It is the ideal screening specimen to test substances that require concentration or incubation (e.g, nitrites and protein).

• It is ideal for patients subjected to pregnancy testing because it prevents false-negative pregnancy test results.

• It evaluates and confirms orthostatic proteinuria.

Random specimen

• This is the most commonly received urine specimen.

• Useful for routine screening tests to detect obvious abnormalities.

• It may show erroneous results due to the different factors that could affect the content or the composition of the patient's urine sample.

Timed collection: 24 hour specimen

• This is ideal for quantitative urine assay; it can be a 12-hour or 24 24-hour urine specimen.

• the specimen or the urine specimen should always be refrigerated, or it can also be added with a chemical preservative

1. Those collected for a predetermined length of time

2. Collection during a specific time of the day

Two types of timed collection specimen:

Fasting specimen

• 2nd urine voided specimen after fasting.

• Ideal for glucose monitoring.

Two-hour post prandial specimen

• The patient should void their urine first before consuming the routine meal.

• 2 hours after eating, the urine specimen is collected and tested for glucose.

Glucose tolerance specimens

• True for pregnant women.

• The collection corresponds with blood samples drawn during the glucose tolerance testing.

• The urine sample is only tested for glucose and ketone.

• The results are reported along with the blood test results.

Prostatic specimen

For the determination of prostatic infection.

Second specimen

In three glass collection procedure, which specimen in the control?

1. Three Glass Collection Procedure

2. Pre and Post Massage Test (PPMT)

Two types of collection for prostatic specimen:

prostatic massage

In pre and post massage test, the second urine collection is done after a?

1. Routine Void

2. Midstream Clean-Catch Specimen

3. Suprapubic Aspiration

4. Catherized Specimen

5. Pediatric Specimen

What are the urine collection techniques?

Routine void

No patient preparation and only have to instruct the patient to urinate in an appropriate container.

Midstream clean-catch urine

• There will be cleansing materials provided, and you will instruct the patient to cleanse the area thoroughly for the collection of the urine sample.

• Give the patients a sterile container, ideal in bacterial culture that the interior of the container does not come in contact with the patient's hand or the perineal area of the patient.

Suprapubic aspiration-

• Invasive procedure, uses a needle and a syringe.

• External introduction of a needle through the abdomen into the bladder.

• Especially useful for bacterial cultures, especially if the physician wants to know if there are any anaerobic microbes, and for infants, where specimen contamination is unavoidable.

Catherized specimen

• Collected under sterile conditions.

• Most commonly used for bacterial culture.

1. urethral

2. ureteral

two types of catherized specimen:

Urethral

• A catheter that is inserted into the bladder via the urethra.

• The urine will flow directly from the bladder through the catheter and into the plastic bag.

• This specimen can be used for bacterial and fungal culture and routine urinalysis screening.

Ureteral

• the urine is collected directly from the left or right ureter.

• To differentiate a kidney infection, either from the right kidney or the left kidney, because it is directly inserted.

Pediatric specimen

Use a soft, clear plastic bag with a hypoallergenic skin adhesive attached to the genital area.

10 t0 15 mL

The capacity of the urine container should be?

12 mL

How much mL of urine is used for microscopic analysis?

• color

• odor

• pH

• nitrite

• bacteria

What is increased in unpreserved urine?

• clarity

• glucose

• ketones

• urobilinogen

• bilirubin

• RBC and WBC

• casts

What is decreased in unpreserved urine?

Oxidation or reduction of metabolites

What causes the color of the urine to darken?

Bacterial multiplication or breakdown of urea to ammonia

What causes the odor of the urine to increase?

Breakdown of urea to ammonia by urease-producing bacteria/loss of CO2

What causes the pH of the urine to increase?

Multiplication of nitrate-reducing bacteria

What causes Nitrite in the urine to increase?

Multiplication

What causes bacteria in the urine to increase?

Bacterial growth and precipitation of amorphous material

What causes clarity of the urine to decrease?

Glycolysis and bacterial use

What causes clarity in the urine to decrease?

Volatilization and bacterial metabolism

What causes ketones in the urine to decrease?

Exposure to light/photo oxidation to biliverdin

What causes bilirubin in the urine to decrease?

Oxidation to urobilin

What causes urobilinogen in the urine to decrease?

Disintegration in dilute alkaline urine

What causes RBC and WBC casts in the urine to decrease?

2 to 8 degrees Celsius

Refrigeration is most routinely used at?

4 to 8

What is the pH of the urine?

1.002 to 1.035

What is the specific gravity of urine?

32.5 to 37.7 degrees Celsius

Temperature of the urine should be?

Creatinine

is the single most useful substance that identifies that the fluid is a urine sample