V. Urinalysis

Denielle Genesis B. Camato

V. URINALYSIS ANALYSIS OF URINALYSIS AND BODY FLUIDS | REVIEWER

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URINALYSIS

[ Probably the oldest clinical laboratory practice [ Usually involves gross observation and assessment of general appearance,

dipstick analysis, and microscopic assessment [ One of the most commonly performed laboratory test

URINE

[ pale yellow fluid produced by the kidneys, composed of dissolved wastes and excess water or chemical substances from the body

[ produced when blood is filtered through the kidneys

CHANGES IN URINE AT ROOM TEMPERATURE

r Bacteria multiply and may cause turbidity and a positive protein reaction

r Bacteria convert urea to ammonia, which increases pH. r Bacteria metabolize glucose. r RBCs lyse in dilute or alkaline urine. r Casts lyse in alkaline urine. r WBCs disintegrate. r Bilirubin/urobilinogen are lost through exposure to light and/or oxidation. r Ketones are lost through evaporation.

URINE VOLUME

Normal daily volume 1200-1500 mL

Normal day-night ratio 2:1 – 3:1 Diuresis Increased urine production Polyuria >2000 mL/day

r diabetes mellitus r diabetes insipidus

Oliguria <500 mL/day r dehydration r renal disease r obstruction of urinary

tract Anuria No urine production

URINE COLOR AND CLARITY

Urochrome Normal yellow color

Dilute urine Colorless Concentrated urine Dark yellow, amber Bilirubin Yellow-brown or olive green

Yellow foam on shaking Homogentistic acid Normal on voiding

Brown or black on standing Beginning at surface

Melanin Brown or black on standing Methemoglobin Brown or black due to oxidation of

hemoglobin in acid urine Myoglobin “Cola” on standing Blood/hemoglobin Pink or red when fresh

“Cola” or “Smoky” on standing Cloudy with RBCs Clear with hemoglobin

Porphyrin Port-wine Drugs, medications, food Green, blue, orange Pseudomonas infection Green, blue-green Urobilinogen Colorless when excreted

Oxidized to orange-brown urobilin Crystals, WBCs, RBCs, epithelial cells, bacteria

CHEMICAL URINALYSIS BY REAGENT STRIP



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Test Substance(s) Detected Principle Sources of Error Comments Sulfosalicylic acid Protein Acid precipitation False-positive:

Radiographic dyes, tolbutamide, some antibiotics, turbid urine. False-negative: highly buffered alkaline urine

Detects all proteins, including Bence Jones proteins.

Clinitest Reducing substances Copper reduction False-positive: High levels of ascorbic acid. False-negative: Glycolysis, pass through. (Color goes through orange and returns to blue or blue-green. Repeat using two-drop method and two-drop color chart.)

Non-specific. Reacts with glucose, galactose, fructose, maltose, lactose. (Sucrose is not reducing sugar.) Test all infants to diagnose galactosemia. Not as sensitive for glucose as reagent strip. Self-heating method. Perform in rack to avoid burning.

Acetest Ketones Sodium nitroprusside reaction

False-negative: Improperly stored specimen

Most sensitive to acetoacetic acid

Ictotest Bilirubin Diazo reaction Drecreased: exposure to light, improperly stored specimen, high levels of ascorbic acid, nitrites. False-positive: Urine pigments.

More sensitive than reagent strip. Less affected by interfering substances

Watson-Shwartz Test Urobilinogen, porphobilinogen

Ehrlich’s aldehyde reaction

Decreased: exposure to light, more than 1 hour at room temperature. False-positive: Warm aldehyde reaction. (Urine should be at room temperature.)

Collect specimen from 2-4pm. Store in dark. Urobilinogen is soluble in chloroform and butanol. Porphobilinogen is not soluble in either.

Hoesch Test Porphobilinogen Ehrlich’s aldehyde reaction

Similar to Watson-Schwartz

Urobilinogen doesn’t react unless very high.

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[ Sources of error may vary with brand of reagent strip. Refer to manufacturer’s package insert.

CONFIRMATORY/ SUPPLEMENT URINE CHEMISTRY TESTS

EFFECT OF HIGH LEVELS OF ASCORBIC ACID ON URINALYSIS TESTS

*May vary with brand of reagent strip. Refer to manufacturer’s package insert.

False-positive False-Negative or Decrease* Clinitest Glucose Blood Bilirubin Nitrite Leukocyte esterase !



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TYPE DESCRIPTION SIGNIFANCE COMMENTS Hyaline Homogenous with

parallel sides and rounded ends

0-2/low power field (LPF) are normal. Increased with stress. Fever, trauma exercise, renal disease

Most common type. Least significant. Contain Tamm-Horsfall protein only. Maybe overlooked if light is too bright

Granular Same as Hyaline but contain granule

0-1/LPF is normal increased with stress, exercise Glomerulonephritis Pyelonephritis

May originate from disintegration of cellular casts.

RBC RBCs in cast matrix Yellowish to orange

color

Acute Glomerulonephritis Strenuous exercise

Pinpoints source of bleeding in kidney. Most fragile of casts. Often in fragments.

Blood Contain hemoglobin. Yellowish to orange

color

Same as RBC cast From disintegration of RBC casts

WBC Leukocytes incorporated into cast matrix.

Irregular in shape

Pyelonephritis Pinpoints kidney as the site of infection

Epithelial cell Renal tubular epithelial cells incorporated into cast matrix

Renal tubular damage Transitional and squamous epithelial cell cast do not exist These cells are found distal to renal tubules and collecting ducts where casts are formed.

Waxy Homogenous Opaque Notched edges Broken ends

Urinary stasis From degeneration of cellular and granular casts Unfavorable sign

Fatty Cast containing lipid droplets

Nephrotic syndrome Maltese crosses with polarized light. Stain with Sudan and oil red O

Broad Wide Maybe cellular, granular

or waxy

Advanced renal disease Formed in dilated distal tubules and collecting ducts. “Renal failure casts.”

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STRUCTURE DESCRIPTION SIGNIFICANCE COMMENTS Bacteria Rods

Cocci Urinary tract infection or contaminant

Usually accompanied by WBCs when clinically significant,unless patient is neutropenic

Yeast 5-7um ovoid colorless smooth refractile May be budding

Usually due to vaginal or fecal contamination. May be due to kidney infection. May be seen in urine of diabetic patients.

Differentiate from RBCs by adding 2% acetic acid. RBCs are lysed Yeast are not. Presence of pseudohyphae indicates kidney function

Sperm 4-6um head with 40-60um tail

Usually not significant in an adult. Maybe a sign of sexual abuse in a child.

Trichomonas Resembles WBC Rapid Jerky Nondirectional motility

Contaminant from genital tract infection

Should not be reported unless motile

Mucus Transparent Long Thin Ribbon-like structure

with tapering ends

Large amount seen with chronic inflammation of urethra or bladder

Maybe mistaken for hyaline casts

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Crystal Description Significance Comments Amorphous urates Irregular granules None From pink precipitate in

bottom of tube. May obscure significant sediment. Dissolved by warming to 60°C

Uric acid Very pleomorphic, Four-sided, six-sided, star-shaped, rosettes, spears, plates. Colorless, red brown, or yellow.

Usually normal Birefringent. Polarized light.

Calcium oxalate Octahedral (eight-sided) envelope form is most common. Also dumbbell and ovoid forms.

Normal Occasionally found in slightly urine. Monohydrate form maybe mistaken for RBCs. Most common constituent of renal calculi.

Leucine Yellow, oily-looking spheres with radial and concentric striations

Severe liver disease Often accompanied by leucine

Cystine Hexagonal (six-sided) Cystinuria Must be differentiated from uric acid. Does not polarize light.

Cholesterol Flate plate with notched out corner. “Star-step”

Nephrotic syndrome Birefringent

Bilirubin Yellowish-brown needles, plates and granules

Liver disease Reagent strip or Ictotest should be positive for bilirubin.

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Crystal Description Significance Comments Amorphous phosphates Irregular granules None Form white precipitate in

bottom of tube. Dissolve with 2 acetic acid.

Triple phosphate “coffin-lid” crystal None Ammonium biurate Yellow-brown

“thorn apples” spheres

None Seen in old specimens

Calcium phosphate Needles Rosettes “pointing finger”

None Only needle form seen in alkaline urine

Calcium carbonate Colorless dumbbells None !

CELL DESCRIPTION ORIGIN CLINICAL SIGNIFANCE

COMMENTS

Squamous epithelial cell

40-50 um. Flat Prominent round nucleus

Lower urethra, Vagina

Usually none. Improperly collected clean-catch specimen

May form syncytia

Transitional epithelial cell

40-50 um. Spherical, pear shaped, or polyhedral. Round central nucleus.

Renal pelvis, ureters, bladder, upper urethra

Seldom significant May form syncytia

Renal tubular epithelial cell

Slightly larger than WBC. Round. Eccentric round nucleus

Renal tubules Same as renal tubular epithelial cells

Maltese crosses with polarized light.

White blood cell (WBC)

Usually polymorphonuclear. Approximately 12um. Granular appearance

Kidney, bladder, or urethra

Cystitis, pyelonephritis, tumors, renal calculi

0-5/high power field (HPF) are normal. Clumps of WBCs are associated with acute infection.

Glitter cell WBC Brownian movement of granules. Stain faintly or not at all.

Same as WBC Same as WBC Seen in hypotonic urine

Red blood cell (RBC) Biconcave disk, approximately 7um. Smooth. Non-nucleated.

Kidney, bladder, urethra

Infection, trauma, tumors, renal calculi. Dysmorphic RBCs indicate glomerular bleeding.

Crenated in hypertonic urine. Lyse in hypotonic urine and with 2% acetic acid.

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CELLS IN THE URINE SEDIMENT

CRYSTAL FOUND IN ACID OR NEUTRAL URINE

CRYSTALS FOUND IN ALKALINE URINE

CASTS

MISCELLANEOUS URINE SEDIMENT



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XXX PICTURES XXX

1. TRIPLE PHOSPHATE

2. CALCIUM OXALATE

3. CYSTINE

4. URIC ACID

5. LEUCINE

6. CALCIUM PHOSPHATE

7. AMMONIUM BIURATE

8. AMORPHOUS POSHPHATES

9. TYROSINE

10. CHOLESTEROL CRYSTAL

11. STAR-SHAPED URATE

12. FINE GRANULAR CAST

13. FATTY CAST



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14. RBC CAST

15. WBC CAST

16. GRANULAR CAST

17. WAXY CAST

18. HYALINE CAST

19. BROAD CAST

20. BACTERIA

21. SQUAMOUS EPITHELIAL CELLS

22. COTTON FIBERS ‘

23. YEAST

24. SPERMATOZOA (2-HEADED)

25. SCHISTOSOMA HAEMATOBIUM

26. TRICHOMONAS VAGINALIS

27. RENAL TUBULAR CAST

28. OVAL FAT BODY

V. Urinalysis

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