AUBF_Prelims_Lec: Intro to Urinalysis

Edwin Smith Surgical Papyrus

Egyptian hieroglyphics stating the analysis of urine with gives birth to laboratrory medicine

Hippocrates (5th Century BC)

He Wrote a book on “uroscopy”

1140 AD

This is the year where Color charts had been developed that described the significance of 20 dfferent colors

Thomas Bryant

he made a book about charlatans (pisse prophets) that only guess a person’s illness by visually analyzing the urine

17th Century

—invention of the microscope led to the examination of urinary sediment

Interpret the colors of urine that denotes what conditions

• Red

• Black

• Amber

Red - blood/bleeding

Black - melanin pigment

Amber - liver disease, antibiotics, vitamins, coffee.

Thomas Addis

Examination of urinary sediment — method of quantitating the microscopic sediment

Richard Bright

Introduced concept of urinalysis as part of doctor’s routine patient examination

1930s

urinalysis disappeared from routine examination

Urine

known as the ULTRAFILTRATE of plasma

Urinalysis

CLSI defined it as “the testing of urine with procedures commonly performed in an expeditious, reliable, accurate, safe, and cost- effective manner”

Reason for performing urinalysis

➢ Aiding in the diagnosis of disease o doctor will do some predictive analysis base on urine color

➢ Screening asymptomatic populations undetected disorders

➢ Monitoring the progress of disease; and

➢ Effectiveness of therapy

Urea

Major organic component; metabolic waste product produced in the liver from the breakdown of protein and amino acids.

Creatinine

derived from creatine, nitrogenous substance in muscle tissue

Urine Composition

Normally 95% Water, 5% Solute

Uric acid-

common component in kidney stones; derived from catabolism of nucleic acid in food

Hippuric acid-

Benzoic acid is eliminated in this form, increases with high vegetable diet.

Explain why some inorganic components are being reabsorbed by the kidneys

• The body reabsobrs such substances because they are needed by the body

Inorganic Components of Urine

• Sodium Chloride - major inorganic component (Principal salt)

• Potassium

• Sulfate - derived from AA

• Phosphate

• Ammonium

• Magneiusm

• Calcium

How to determine if the fluid receieved is urine?

• the sole substance that makes identify it is urine, if it has a high creatinine concentration (50x the value of a plasm)

• Higher concentration of Urea, Sodium and Chloride

Normal urine output

1. For normal wate intake

2. Those who intake a lot of water (normal)

1. 1200 to 1500 mL

   1. 600 to 2000 mL

Oliguria in

Infants
Children
Adults

Infants	< 1ml/kg/hr
Children	<0.5
Adults	<400

Anuria

> caused by

Cessation of urine flow result from any serious damage to the kidney or decrease flow of blood to the kidney

NOCTURIA

• increase in excretion of urine during the night

True

T/F

Normally, kidneys excrete 2 or 3 times more urine during the day

Explain the relationship between urine output and ADH (Antidiuretic Hormone)

high ADH = lower urine output (urinate less)

low ADH = high urine output (urinate more)

Diabetes Mellitus Polyuria

• This a type of polyuria which is caused by a low production of insulin or its function resulting in high glucose level.

• Exceeds the renal threshold for glucose

  • high S.G.

Diabetes Insipidus Polyuria

• a condition due to decrease prodx. or function of ADH

• water is not reabsorbed = low S.G.

How are D.M. Polyuria and D.I. Polyuria compensated (to keep it in balance)

• compensated with polydipsia (excessive thrist)

Rejection Criteria for Urine Specimen

1. Specimens in unlabeled containers

2. Nonmatching labels and requisition forms

3. Specimens contaminated with feces or toilet paper

4. Containers with contaminated exteriors

5. Specimens of insufficient quantity

6. Specimens that have been improperly transported

3 Ps of Diabetes Mellitus

• Polyuria

• Polydipsia

• Polyphagia

First Morning specimen

• Also known as the 8 hour specimen

• The ideal screening specimen

• It is a concentrated specimen

Use/Purpose of First Morning Specimen

• •Essential for preventing false- negative pregnancy tests

• For evaluating orthostatic proteinuria

RANDOM SPECIMEN

 Collected anytime without patient preparation  Most commonly received specimen  Satisfactory for routine screening

FASTING SPECIMEN (Second Morning)

 Second voided specimen after a period of fasting

 This specimen will not contain any metabolites from food ingested before the beginning of the fasting period

A normal Dastng Specime should have a (+/-) result in glucose?

(-) negative

• a specimen in which the patient voided before and after consuming a routine meal (2 hrs after eating)

Purpose/significance of 2 hour-postprandial specimen

• for insulin therapy monitoring

• also tested for glucose

Glucose Tolerance Specimen

> Define

> Purpose?

• collected together with GTT in the blood

• tested for glucose and ketones

24 hour specimen

Specimen used for urine quantitative assay

All specimen should be refrigerated or kept on ice during the collection period.

Midstream clean catch

• spx. for bacterial culture and routine analysis

• a less traumatic method for obtaining urine

CATHETERIZED SPECIMEN

Obtained following catheterization of the patient, that is, insertion of a sterile catheter through urethra into the bladder.

Catheterized specimen is sent for what test/purpose?

bacterial culture

SUPRAPUBIC ASPIRATION TECHNIQUE

Involves collecting urine directly from the bladder by puncturing the abdominal wall and distended bladder using needle and syringe.

Suprapubic aspiration technique

• provides a sample for bacterial culture that is completely free of extraneous contamination.

• can also be used for cytologic examination

Prostatitis Specimen

• aka “three glass collection”

• specimen used for diagnosis of prostatitis

FIll the info for the different containers in Prostatitis specimen

Container and location	Contain	Assess/Determines
1st container (Urethra)
2nd container (Bladder)
3rd container (Prostate)
4th container (Prostate)

Container and location	Contain	Assess/Determines
1st container (Urethra)	→first passed urine	Urethral infection or inflammation
2nd container (Bladder)	→ midstream portion of urine	Cystitis
3rd container (Prostate)	→ urine with prostatic fluid	Prostatic infection
4th container (Prostate)	post prostatic massage urine specimen (Stamey –Mears)	Prostatic infection

Drug specimen collection (things to consider)

• Vol of urine

• Urine temp

• 60 mL in PH (30-45 mL international)

• 32.5-37.7 C

Characteristics of an ideal preservative for urine

• Bactericidal

• Inhibits Urease

• Able to preserve formed elements

• Must not interfere with chemical tests

Type	Advantage	Disadvantage	Use
Refrigeration

Type	Advantage	Disadvantage	Use
Refrigeration	Acceptable for routine U/A for 24 hours  • Acceptable for urine culture; inhibits bacterial growth for 24 hours • INEXPENSIVE	•Precipitates amorphous and/ or crystalline solutes •Increases Specific gravity	Storage before and after testing

Type	Advantage	Disadvantage	Use
Thymol

Type	Advantage	Disadvantage	Use
Thymol	• Preserves glucose & sediment elements (cast & cell)  • Inhibits bacterial and yeast growth	• Interferes with acid precipitation test for protein	Sediment preservation

Type	Advantage	Disadvantage	Use
Formalin

Type	Advantage	Disadvantage	Use
Formalin	• Excellent cellular preservative	• Act as reducing agent, interfere with urine chemical test (glucose, blood, leukocyte esterase & copper reduction)	Cytology

Type	Advantage	Disadvantage	Use
Saccomano fixative

Type	Advantage	Disadvantage	Use
Saccomano fixative	• Preserves cellular elements	•Potential chemical hazard	Cytology

Type	Advantage	Disadvantage	Use
Concentrated HCl

Type	Advantage	Disadvantage	Use
Concentrated HCl	•A good preservative for drug analyses	• Unacceptable for urinalysis testing	For quantitative analysis

Type	Advantage	Disadvantage	Use
Boric Acid			(-)

Type	Advantage	Disadvantage	Use
Boric Acid	• Preserves protein  • Does not interfere with routine analyses except pH	• Interferes pH determination	(-)

Type	Advantage	Disadvantage	Use
Sodium carbonate

Type	Advantage	Disadvantage	Use
Sodium carbonate	• Inexpensive •Stabilizes porphyrins, porphobilinogen	• Unacceptable for urinalysis testing	Quantitative analysis of porphyrins, porphobilinogen

Type	Advantage	Disadvantage	Use
Toluene			(-)

Type	Advantage	Disadvantage	Use
Toluene	• Does not interfere with routine tests	• Floats on surface of specimen and clings to pipettes	(-)

Type	Advantage	Disadvantage	Use
Phenol			(-)

Type	Advantage	Disadvantage	Use
Phenol	• Does not interfere with routine tests	• Causes an odor change	(-)

Component	Observation (decrease or increase)	Mechanism
Color

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Color	Darkens or changes	Oxidation/reduction of solutes (x:Bilirubin

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Clarity

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Clarity	decreases	Crystal precipitation Bacterial proliferation

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Odor

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Odor	Ammoniacal,foul smelling	Bacteria convert urea Ammonia

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
pH

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
pH	Increase (alkaline urine)	Loss of CO2 ; Ammonia formation

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Glucose

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Glucose	Decrease	Consumed by cells and bacteria

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Ketones

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Ketones	Decrease	Volatilization

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Bilirubin

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Bilirubin	Decrease	Photooxidation by light exposure

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Urobilinogen

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Urobilinogen	Decrease	Oxidation to urobilin

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Nitrite

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Nitrite	Increase	Bacteria converts nitrate-nitrite

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Blood cells

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Blood cells	Decrease	Lysis of cells

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Casts

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Casts	Decrease	Disintegration

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Bacteria

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Bacteria	Increase	Proliferation of bacteria

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Trichomonads

Changes in unpreserved urine

Component	Observation (decrease or increase)	Mechanism
Trichomonads	Decrease	Loss of Characteristic motility and death

Comoponents of Saccomano Fixative

• Ethanol

• Polyethylene Glycol (PEG)