II : Introduction to Urinalysis

Urinalysis

- The testing of urine with procedures commonly performed in an expeditious, reliable, accurate, safe & cost-effective manner. (CLSI)

T

Analyzation of urine was actually the beginning of laboratory medicine. (t/f)

Egyptian hieroglyphics

References to the study of urine can be found in the drawings of caveman in -, such as the Edwin Smith Surgical Papyrus.

• Color

• Turbidity

• Odor

• Volume

• Viscosity

• Sweetness – certain spx attracted ants or tasted sweet

Diagnostic Information

T

In diagnostic information, to test the sweetness of urine they used to detect if they are attracted by ants to test if it tasted sweet or not. (t/f)

5th Century BCE

Hippocrates wrote the book of Uroscopy

Uroscopy

During the 5th Century BCE, Hippocrates wrote the book of -

1140 CE

Color chart has been developed that described the significance of 20 different color

1694 – Frederik Dekker’s

Discovery of albuminuria by boiling urine.

Charlatans

-Urinalysis became compromised when -/ or “pisse prophets” without medical credentials began offering their predictions to the public for a health fee.

“pisse prophets”

Charlatans is aka

Charlatans

They became the subject of a book published by Thomas Bryant in 1627.

England

Passing of the 1^st medical licensure laws

17th Century – Thomas Addis

·    Invention of microscope led to the examination of urinary sediment.

17^th Century – Thomas Addis

The development by Thomas Addis of method for quantitating the microscopic sediment.

17^th Century – Thomas Addis

The development by - of method for quantitating the microscopic sediment.

1827 – Richards Bright

Introduced the concept of urinalysis as part of a doctor’s routine px examination.

1930s

Urinalysis began to disappear from routine examinations.

• Readily available & easily collected.

• Contains information which can be obtained by inexpensive laboratory test about many of the body’s major metabolic functions.

2 Unique Characteristics Of A Urine Spx Account For This Continued Popularity:

ultrafiltrate of plasma

Urine Formation

• Kidneys continuously form urine as an -.

170, 000 mL

Urine Formation

- – Filtered Plasma

1, 200 mL

Urine Formation

– Average daily urine output depending on fluid intake

95%

Urine Composition

- water

5%

Urine Composition

_ solutes

1. Dietary intake

2. Physical activity

3. Body metabolism

4. Endocrine functions

Urine Composition

·    Factors that Affect Concentration of Solutes:

↓ water output

·    Dietary intake – watermelon:

↓ urine output,

↑ conc. of solutes

·    Physical activity:

- urine output,

- conc. of solutes

1. Urea

2. Creatinine

3. Uric Acid

4. Chloride

5. Sodium

6. Potassium

7. Phosphate

8. Ammonium

9. Calcium

Primary Components of Normal Urine

Urea

-Primary organic component

Urea

Product of metabolism of protein & amino acids

Creatinine

Product of metabolism of creatine by muscles

Uric Acid

Product of breakdown of nucleic acid in food & cells

Chloride

-Primary inorganic component

Chloride

Found in combination with sodium (table salt) & many other inorganic substances.

Sodium

Primarily from salt, varies by intake

Potassium

Combined with chloride & other salts

Phosphate

Combines with sodium to buffer the blood

Ammonium

Regulates blood & tissue fluid acidity  

Calcium

Combines with chloride, sulfate & phosphate

• Hormones

• Vitamins

• Medications

Others Components of Normal Urine

• Cells

• Cast

• Crystals

• Mucus

• Bacteria

Formed Elements of Components of Normal Urine

Nitrate

Normal urine constituent

• Fluid intake

• Fluid loss from non-renal sources

• Variations in the secretion of antidiuretic hormone

• Need to excrete increased amounts of dissolved solids (glucose/salts)

Factors that Influence Urine Volume

1200 – 1500 mL

Total / Normal Urine Output

600 – 2000 mL

Average Range of Urine Output

Oliguria  

Urine Volume

-↓ urine output

<1 mL / kh/ hr

Urine Volume

Oliguria

: Infants

<0.5 mL / kh/ hr

Urine Volume

Oliguria

- : Children (bc they eat solids unlike infants who drinks liquids/milk)

<400 mL / kh/ hr

Urine Volume

Oliguria

- : Adults

• Dehydration

• Vomiting

• Diarrhea

• Perspiration

• Severe burns

Urine Volume

Cause/s of Oliguria

Anuria

Urine Volume

Cessation of urine flow

• Serious damage to the kidnyes

• From a ↓ flow of blood to the kidney

Urine Volume

Cause/s of Anuria

Nocturia

Urine Volume

↑ Excretion of urine during the night

Polyuria

Urine Volume

↑ In daily urine volume

2.5 – 3  mL/kg/day

Urine Volume

Polyuria

- in children

  >2.5 L/day in adults

Urine Volume

Polyuria

- in adults

• Diabetes Mellitus

• Diabetes Insipidus

• Diuretics

• Caffeine

• Alcohol

Urine Volume

Cause/s of Polyuria

Diabetes Mellitus

– caused by a defect in the pancreatic production of insulin or in the function of insulin, which results in an ↑ concentration of body glucose.

Diabetes Insipidus

– ↓ production of ADH; water necessary for adequate body hydration is not reabsorbed from the plasma filtrate.

ADH

diuretics, caffeine & alcohol suppresses the secretion of -

Polydipsia

↑ Ingestion of water

Diabetes Insipidus

• Decreased SG

• Decreased production/function of ADH

Diabetes Mellitus

• Increased SG

• Decreased insulin / function of insulin

• Increased glucose

Clean, dry, leak-proof container

Specimen Collection

container should be

·    Wide mouth – to facilitate collections from female px

·    Flat bottom – prevent overturning

·    Clear material – allow for determination of color & clarity

·    50 mL – allows 12 mL of spx needed for microscopic analysis, additional spx for repeat analysis, & enough room for the spx to be mixed by swirling the container.

Specimen Collection

Container

·    Routine Urinalysis:

Wide mouth

Specimen Collection

Container

·    Routine Urinalysis:

to facilitate collections from female px

Flat bottom

Specimen Collection

Container

·    Routine Urinalysis:

prevent overturning

50 mL

Specimen Collection

Container

·    Routine Urinalysis:

– allows 12 mL of spx needed for microscopic analysis, additional spx for repeat analysis, & enough room for the spx to be mixed by swirling the container.

Clear material

Specimen Collection

Container

·    Routine Urinalysis:

allow for determination of color & clarity

·    Px’s 1^st & last name

·    Identification #

·    Date & Time of collection

·    Additional info:

• ·    Age / gender

• ·    Location of the healthcare facility

• ·    Health-care provider’s name

• ·    Preservatives used (if any as required by facility protocol)

Specimen Collection

Label includes:

F

Labels must be attached to the container not to the lid

Specimen Collection

Label (t/f)

·    Labels must be attached to the lid not to the container

T

Specimen Collection

Label (t/f)

Should not be detached if container is refrigerated or frozen

• Spx in unlabeled containers

• Nonmatching labels & requisition forms

• Spx contamined with feces/toilet paper

• Containers with contaminated exteriors

• Insufficient quantity of spx

• Spx that have been improperly transported.

• Spx that have not been preserved correctly during a time delay.

• Spx for urine collected in a nonsterile container.

• Inappropriate collection for the type of testing needed (i.e., midstream clean-catch spx for bacterial culture)

Specimen Collection

Spx rejection

Within 2 hrs ( a spx that cannot be delivered & tested within 2 hrs should be refrigerated or have an appropriate chemical preservative added)

Specimen Handling

Spx Integrity should be handled within

refrigerated or have an appropriate chemical preservative added

Specimen Handling

Spx Integrity should be handled within 2hrs, a spx that cannot be delivered & tested within 2 hrs should be -

Color

Specimen Handling

Changes in Unpreserved Urine

Change: Modified / darkened

Cause: Oxidation/reduction of metabolites

Clarity

Specimen Handling

Changes in Unpreserved Urine

Change: ↓

Cause:

• Bacterial growth

• Precipitation of amorphous material

Odor

Specimen Handling

Changes in Unpreserved Urine

Change:↑ Ammonia Smell

Cause: Bacterial multiplication causing breakdown of urea to ammonia

pH

Specimen Handling

Changes in Unpreserved Urine

Change: ↑

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

Glucose

Specimen Handling

Changes in Unpreserved Urine

Change: ↓

Cause:

• Glycolysis use

• Bacterial use

Ketones

Specimen Handling

Changes in Unpreserved Urine

Change: ↓

Cause:

• Volatilization

• Bacterial metabolism

Bilirubin

Specimen Handling

Changes in Unpreserved Urine

Change: ↓

Cause: Exposure to light/photo oxidation to biliverdin

Urobilinpgen

Specimen Handling

Changes in Unpreserved Urine

Change: ↓

Cause: Oxidation to bilirubin

Nitrite

Specimen Handling

Changes in Unpreserved Urine

Change: ↑

Cause:

Multiplication of nitrate-reducing bacteria

RBC & WBC & Casts

Specimen Handling

Changes in Unpreserved Urine

Change: ↓

Cause: Disintegration/lyse in dilute alkaline urine

Bacteria

Specimen Handling

Changes in Unpreserved Urine

Change: ↑

Cause:

Multiplication

TrichoMonas

Specimen Handling

Changes in Unpreserved Urine

Change: ↓

Cause:

• Loss of motility

• Death

·    2 – 8 °C Refrigeration – ↓bacterial growth & metabolism

Specimen Handling

Spx Preservation ideal temp

·    2 – 8 °C Refrigeration

Specimen Handling

Spx Preservation

– ↓bacterial growth & metabolism

• Bactericidal

• Inhibit urease

• Preserved formed elements in the sediment

• Not interfere with chemical tests

Specimen Handling

Spx Preservation

Ideal preservative:

Refrigeration

Specimen Collection

Advantage: Does not interfere with chemical tests

Refrigeration

Specimen Collection

Disadvantage: Precipitates amorphous phosphates & urates

Refrigeration

Specimen Collection

Prevents bacterial growth for 24hrs

Boric acid

Specimen Collection

Advantage: Prevents bacterial growth & metabolism

Boric acid

Specimen Collection

Disadvantage: Interferes with analysis of drugs & hormones

Boric acid

Specimen Collection

Keeps pH at about 6.0 that can be used for transport urine transport cultures

Formalin (Formaldehyde)

Specimen Collection

Advantage: Excellent sediment preservative

Formalin (Formaldehyde)

Specimen Collection

Disadvantage: Acts as reducing agent, interfering with chemical tests for glucose, blood, leukocyte esterase, & copper reduction.

Formalin (Formaldehyde)

Specimen Collection

Rinse spx container with formalin to preserve cells & casts

Sodium fluoride

Specimen Collection

Advantage: Good preservative for drug analyses