Unit 2. Urine Volume, Composition, & Types of Specimen

Urine

is a complex, yellowish fluid that is considered as an ultrafiltrate of plasma from which glucose, amino acids, water and other substances essential to body metabolism have been reabsorbed.

1200-1500 ml

The average daily urine output is about

• Dietary intake

• Physical activity

• Body metabolism

• Endocrine functions

Factors that could affect urine concentration

• Urea

• Creatinine

• Uric Acid

Organic Components of Urine

• Chloride

• Sodium

• Potassium

• Phosphate

• Ammonium

• Calcium

Inorganic Components of Urine

Urea

URINE COMPOSITION:

• a metabolic waste product produced in the liver from the breakdown of protein and amino acids

• accountsfor nearly half of the total dissolved solids in urine

Creatinine

URINE COMPOSITION:

• Product of metabolism of creatine by muscles

Uric Acid

URINE COMPOSITION:

• Product of breakdown of nucleic acid in food and cells

CHLORIDE

URINE COMPOSITION:

• Primary inorganic component. Found in combination with sodium (table salt) and many other inorganic substances

SODIUM

URINE COMPOSITION:

• Primarily from salt, varies by intake

POTASSIUM

URINE COMPOSITION:

• Combined with chloride and other salts

PHOSPHATE

URINE COMPOSITION:

• Combines with sodium to buffer the blood

AMMONIUM

URINE COMPOSITION:

• Regulates blood and tissue fluid acidity

CALCIUM

URINE COMPOSITION:

• Combines with chloride, sulfate, and phosphate

Creatinine, urea, sodium and chloride content are higher in urine than in other body fluids.

• Urea nitrogen = 600mg/100mL

• Creatinine = 50mg/100mL

How do you determine whether a specimen is urine??

Proteins & glucose

______ and ______ are not present in a normal urine spx.

URINE VOLUME

• Determines by the body’s state of hydration

• depends on the amount of water that the kidneys excrete

• affected by

  • fluid intake

  • fluid loss from nonrenal sources

  • variations in ADH secretion

  • need to excrete increases amounts of dissolved solids (glucose, salts)

1200-100 mL

Normal daily urine output:

600-2000 ml

Normal range for urine

Polyuria

It is because of persistent production of more than 2000-3000ml of urine in 24 hours.

associated with diabetes mellitus and diabetes insipidus.

Oliguria

It is related to an abnormal decrease in urine output.

It is observed in dehydration, renal insufficiency, poorly compensated heart disease, calculi formation, kidney tumors.

From excessive water loss from vomiting, diarrhea, perspiration, severe burns

hypersthenuria (1.030)

Oliguria is always accompanied by _______________

Anuria

It pertains to the total suppression of urine production or complete cessation or blockage or urine flow.

It can be seen in severe acute nephritis, mercury poisoning, obstructive uropathy and kidney failure.

From any serious damage to the kidneys or from a decrease in the flow of blood to the kidneys

Nocturia

It is related to the excretion of more than 500 ml urine at night.

apparent in individuals with chronic progressive renal failure.

isosthenuria

Nocturia is always accompanied by___________ or low urine specific gravity which indicates loss of concentrating ability of the tubules.

Infants: <1 ml/kg/hr

Children: <0.5 ml/kg/hr

Adults: <400 ml/day

Oliguria urine output levels

Children: >2.5-3 ml/kg/day

Adults: >2.5L/day

Polyuria urine output levels

Hypersthenuria

• Indicates a concentrated urine.

• >1.010 specific gravity

Isosthenuria

• Indicates a urine that is neither concentrated nor diluted.

• ≈ 1.010 specific gravity

hyposthenuria

• Indicates a dilute urine.

• < 1.010 specific gravity

Diuresis

It is transitory increase in urine volume due to intake of diuretics (alcohol, caffeine, polydipsia)

Diabetes mellitus

Caused by defects in insulin production or function, leading to high body glucose levels. The kidneys cannot reabsorb excess glucose, resulting in high urine output with high specific gravity due to increased glucose content.

Diabetes insipidus

Results from decreased ADH production or function, leading to inadequate water reabsorption from plasma filtrate. The urine is truly dilute with low specific gravity.

RANDOM URINE SAMPLE (OCCASIONAL URINE SAMPLE)

TYPES OF URINE SPECIMEN:

• It is a specimen that is collected anytime of the day and is commonly used as a routine screening test for disease diagnosis.

• Spx received most commonly

• Is affected by the most recent food, most recent activity, and most recent medication and supplement.

• Prone to erroneous results

FIRST MORNING URINE SAMPLE

TYPES OF URINE SPECIMEN:

• It is the first urine that is voided in the day after a person has assumed a supine position.

• A concentrated specimen (acidic), ensuring detection of chemicals and formed elements that may not be present in a dilute random specimen

• Delivered to the laboratory within 2 hrs after collection or kept refrigerated.

• routine screening

• pregnancy testing

• detection of orthostatic proteinura

TYPES OF URINE SPECIMEN:

• First Morning Urine specimen is used for (3)

ovary cancer

Positive pregnancy test w/out intercourse in female could mean

testicular cancer

Positive pregnancy test w/out intercourse in male could mean

FASTING/SECOND MORNING URINE SAMPLE

TYPES OF URINE SPECIMEN:

• It is intended for diabetic screening or monitoring.

2-HOUR POST PRANDIAL

TYPES OF URINE SPECIMEN:

• Monitoring Insulin Therapy

1. Give glucose load

2. Wait for 2hrs

3. Check for glucose in the urine (glucose should decrease/negative.

   • If it is positive, it means that the insulin therapy is not working

GLUCOSE TOLERANCE SPECIMEN

TYPES OF URINE SPECIMEN:

• Collected along with OGTT Samples

• Tested for Glucose and Ketones

• The number of specimens varied with the length of the test. GTTs included fasting, half-hour, 1-hour, 2- hour, and 3-hour specimens and possibly 4-hour, 5- hour, and 6-hour specimens.

renal threshold

TYPES OF URINE SPECIMEN:

• GLUCOSE TOLERANCE SPECIMEN results are correlated with the _______________ for glucose.

GLUCOSE TOLERANCE SPECIMEN

TYPES OF URINE SPECIMEN:

EARLY AFTERNOON SPECIMEN

TYPES OF URINE SPECIMEN:

• It is intended for urobilinogen determination (alkaline tide)

• Usually collected at 2-4pm.

12-HOUR MORNING SPECIMEN

TYPES OF URINE SPECIMEN:

• ADDIS COUNT

• 37% - 47% Formalin is used

24-HOUR SPECIMEN

TYPES OF URINE SPECIMEN:

• For the detection of analytes that are affected by diurnal variations and daily activities e.g. solutes such as catecholamines, 17-hydroxysteroids, and electrolytes in which the lowest concentration is in the early morning and the highest concentration occurs in the afternoon.

• Patient must begin and end the collection period with an empty bladder.

T

T or F

In 24-hour specimen collection, if the concentration of a particular substance remains constant, the specimen may be collected over a shorter period.

24-HOUR SPECIMEN

TYPES OF URINE SPECIMEN:

• Used for measuring the Glomerular Filtration Rate (GFR) and for hormonal studies.

TYPES OF URINE SPECIMEN:

• It is a sample wherein about 30-45 ml. of urine is collected within 4 minutes.

32.5 - 37.7°C.

TYPES OF URINE SPECIMEN:

• Drug specimen's temperature is also measured, and it should be within __________

Chain of Custody

a documented process that tracks the collection, transfer, handling, and storage of evidence or samples to ensure their integrity and prevent tampering throughout the testing or legal process.

East Avenue Medical Center (EAMC)

NRL for Confirmatory Drug Test (URINE)

MIDSTREAM CLEAN-CATCH

TYPES OF URINE SPECIMEN:

• It is the least traumatic routine screening for urinalysis and bacterial culture. It is usually the method of choice for obtaining non-contaminated specimens

MIDSTREAM CLEAN-CATCH

TYPES OF URINE SPECIMEN:

THREE-GLASS URINE COLLECTION

TYPES OF URINE SPECIMEN:

• It is used for prostatic infection determination.

• In collecting this sample, all portions, beginning, middle, and final portion of the void, are collected in three separate containers.

third container.

TYPES OF URINE SPECIMEN:

• In 3-glass urine collection, the prostate is massaged prior to collection in the ___________

bacterial culture (100,000 colony of bacteria is seen)

confirmatory test for UTI

CT scan, MRI, etc.

confirmatory test for Prostatitis

CATHETERIZED SPECIMEN

TYPES OF URINE SPECIMEN:

• It is used if the patient is having difficulty voiding. It can also be used in a female patient to avoid vaginal contamination, especially during menstruation.

SUPRAPUBIC ASPIRATION

TYPES OF URINE SPECIMEN:

• It is a process of collecting bladder urine for bacterial culture and cytology.

• Sometimes, it is used in place of catheterization for obtaining a single urine sample.

• Completely free of extraneous contamination, particularly in infants or children.

bags with adhesive

URINE CONTAINER:

• for the collection of pediatric specimens

50 ml

URINE CONTAINER:

• The recommended capacity of the container is ____

Individually packaged sterile containers with secure closures

URINE CONTAINER:

• should be used for microbiological studies of urine

• Sterile containers

URINE CONTAINER:

• ___________ are also suggested if more than 2 hours elapse between specimen collection and analysis.

False

Labels must be attached to the container, not to the lid, and should not become detached if the container is refrigerated or frozen.

T or F

Labels must be attached to the lid, and not to the container to avoid contamination.

1. Specimens in containers that are unlabeled or improperly labeled

2. Labels and requisition forms that do not match

3. Specimens contaminated with feces or toilet paper

4. Containers with contaminated exteriors

5. Specimens of insufficient quantity

6. Specimens that have been transported improperly

7. Specimens that have not been preserved correctly during a time delay

8. Specimens for urine culture collected in a nonsterile container

9. Inappropriate collection for the type of testing needed (for example, midstream clean-catch specimen for bacterial culture)

Grounds for Specimen rejection

Oxidation or reduction of metabolites

CAUSES OF THE CHANGES IN UNPRESRVED URINE

• Color: Modified/Darkened

Bacterial growth and precipitation of amorphous material

CAUSES OF THE CHANGES IN UNPRESRVED URINE

• Clarity: decreased

Bacterial multiplication causing breakdown of urea to ammonia

CAUSES OF THE CHANGES IN UNPRESRVED URINE

• Odor: Increased ammonia smell

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

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• pH: increased

Glycolysis and bacterial use

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• Glucose: dereased

Volatilization and bacterial metabolism

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• Ketones: Decreased

Exposure to light/photo oxidation to biliverdin

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• Bilirubin: Decreased

Oxidation to urobilin

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• Urobilinogen: Decreased

Multiplication of nitrate-reducing bacteria

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• Nitrite: Increased

Disintegration/lyse in dilute alkaline urine

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• Red and white blood cells and casts: Decreased

Multiplication

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• Bacteria: Increased

Loss of motility, death

CAUSES OF THE CHANGES IN UNPRESERVED URINE

• Trichomonas: Decreased

refrigeration (2-8°C)

SPECIMEN PRESERVATION:

• The method of preservation used most routinely is

• which decreases bacterial growth and metabolism

refrigerated

24 hrs

room temperature

SPECIMEN PRESERVATION:

• If the urine is to be cultured, it should be __________ during transit and kept refrigerated until cultured, up to_______

• The specimen must return to ____________ before chemical testing by reagent strips.

amorphous urate and phosphate crystals

SPECIMEN PRESERVATION:

• Refrigeration also can cause precipitation of ___________________

URINE PRESERVATIVES

URINE PRESERVATIVES

Refrigeration

URINE PRESERVATIVES

Acids (boric acid, HCL, acetic acid, tartaric acid)

URINE PRESERVATIVES

Formalin (formaldehyde)

URINE PRESERVATIVES

Sodium fluoride

URINE PRESERVATIVES

Commercial preservative tablets

URINE PRESERVATIVES

Urine Collection Kits4 (Becton, Dickinson, Rutherford, NJ)

URINE PRESERVATIVES

Light gray and gray C&S tube

URINE PRESERVATIVES

Yellow UA Plus tube

Cherry red/yellow Preservative Plus tube

URINE PRESERVATIVES