Urinalysis Flashcards

Vocabulary flashcards for key terms and concepts in urinalysis.

95% water, 5% solutes (organic and inorganic components)

Normal Urine Composition

Urea

Most Abundant Organic Component of Urine

Chloride

Most Abundant Inorganic Component of Urine

600 - 2000 mL/day

Normal Daily Urine Output Range

1,200 - 1,500 mL/day

Average Daily Urine Output

Anuria

Total suppression of urine production

Nocturia

Excretion of >500 mL urine at night with a specific gravity of <1.018

Diuresis

Transient polyuria following intake of diuretics or substances with diuretic effect

First morning urine

Preferred Urine Specimen for Routine Screening

Orthostatic Proteinuria

Persistent benign proteinuria in young adults after standing, disappears when horizontal

Timed Urine Specimen Collection

Start and end the collection with an empty bladder

24-Hour Urine Specimen

Used for quantitative chemical tests, hormone studies, and clearance tests

2-Hour Afternoon Urine Specimen

Used for urobilinogen determination (peak levels between 2-4 pm)

Fasting Urine Specimen

Either first morning or second morning specimen after a period of fasting

2-Hour Postprandial Urine Specimen

Best for detecting glycosuria/glucosuria; for monitoring of DM

Midstream Clean Catch

Acceptable for bacterial culture and routine urinalysis

Catheterization

Acceptable for bacterial culture and distinguishing between left and right kidneys

Suprapubic Aspiration

Acceptable for bacterial culture and cytology studies

TRUE

TRUE OR FALSE

WBC and bacterial counts in tube 3 must be 10x higher than in tube 1

Stamey-Mears Technique

Four Glass Collection is also known as ______.

Consist of initial voided urine (urethral specimens), midstream urine (bladder specimen), expressed prostatic secretion (during massage) and post-prostatic massage urine (EPS + urine).

Within 2 hours of collection

Urine Transport and Processing Time

Refrigeration

Most preferred Preservative Technique for Urine

Refrigeration Effect on Urine pH

Maintains acid pH up to 8 hours

Toluene

Preservative that floats on surface and clings to pipettes

Boric acid

Preservative that Preserves Protein and Formed Elements Well

Yellow UA Plus Tube

Collection kit w/ no preservative, refrigerate and analyze within 2 hours

Light Gray and Gray C&S tube

Colecction kit that contains boric acid, sodium borate, and sodium formate; prevents bacterial growth for 48 hours at RT

Cherry Red/Yellow Tube

Contains sodium propionate, ethyl paraben, and chlorhexidine; specimen stable for 72 hours at RT

Changes in Unpreserved Urine (>2 hours)

• Color Darkens/Modified

• Odor Intensifies

• More Alkaline pH

• Nitrite Increased

• Bacteria Increased

• Clarity Decreased

• Glucose Decreased

• Ketone Decreased

• Bilirubin Decreased

• Urobilinogen Decreased

• RBCs/WBCs Decreased

• Trichomonas Decreased

Normal Urine Specific Gravity

Random: 1.003 - 1.035, 24-hour: 1.010-1.025

Urinometry

Specific gravity measurement based on density; uses weighted float

Refractometry

Specific gravity measurement based on refractive index

Normal Urine pH

Random 4.5-8; Fasting/First AM 5-6 (slightly acidic)

Benedict's Test

A test for glucose that uses copper reduction reaction

Acetest

A test for ketones which reagent are Sodium nitroprusside, glycine, lactose

Ictotest

Confirmatory test for bilirubin, reagents composed of p-nitrobenezene-diazonium-p-toluene sulfonate, Na2CO3 boric acid, SSA, 0.05 mg/dL in sensitivity

Ehrlich’s Tube Test

Test for Urobilinogen which reagent is PDAB

Purpose of LE test

Detection of bacterial and nonbacterial UTI, Inflammation of the urinary tract.

Mix specimens well before testing.

Technique of specimen to avoid false negative result in blood and leukocyte esterase

Volume of urine examined for STANDARD MANUAL MICROSCOPIC EXAMINATION TECHNIQUE

10-15 mL, average of 12 mL

Centrifugation for STANDARD MANUAL MICROSCOPIC EXAMINATION TECHNIQUE

400 gravity units (RCF) for 5 minutes

Volume of sediment examined for STANDARD MANUAL MICROSCOPIC EXAMINATION TECHNIQUE

20 uL (0.02 mL)

Brightfield

Microscope for routine urinalysis; uses subdued light

Phase-contrast

Microscope for elements with low RI

Polarizing

Microscope for cholesterol-containing cells and casts; birefringent crystals

Sediment Stains

Sternheimer-Malbin, Toluidine blue, Hansel stain, Lipid stains, Prussian blue, Papanicolaou

Hyaline

Major Component: THP/Uromodulin

Refractive Index: ↓ (Same as urine)

Normal no.: 0-2/lpf

Significance: ↑Stress, fever, strenuous exercise, CHF, renal disease.

Crystals in Acidic Urine

• Uric acid

• Amorphous urates

• Acid/Sodium urate

• Calcium oxalate

• Calcium sulfate

• Hippuric acid, Cystine

• Leucine

• Tyrosine

• Bilirubin

• Cholesterol

• Radiographic dye (iatrogenic)

• Sulfonamide

• Ampicillin

Crystals in Alkaline Urine

• Amorphous phosphate

• Calcium phosphate

• Triple phosphate

• Ammonium biurate

• Calcium carbonate

Protein Reagent Strip Principle

Based on Sorensen's protein error of indicators

Glucose Reagent Strip Principle

Utilizes a double sequential enzyme reaction.

Leukocyte Esterase (LE) Test Principle

Detects via Granulocytic esterase reaction following diazo reaction.

Blood Reagent Strip Principle

Detects via pseudoperoxidase activity of heme that catalyzes the oxidation of an indicator.

Ketone Reagent Strip Principle

Detects through a reaction with sodium nitroprusside.

Bilirubin Reagent Strip Principle

Reacts with a diazonium salt to form a colored complex in an acid medium.

Urobilinogen Reagent Strip Principle

Reacts with Ehrlich’s reagent (p-dimethylaminobenzaldehyde) to produce a colored compound.

Nitrite Reagent Strip Principle

Detecs via Greiss reaction.

pH Reagent Strip Principle

Uses a double indicator system to measure pH levels.

Specific Gravity Reagent Strip Principle

Detects pKa change of polyelectrolytes.

Cystinuria

Cause of Sulfur odor

Recto-vesicular fistula

Cause of Fecaloid odor

Trimethyl aminuria

Cause of Rotting fish odor

Acute tubular necrosis

Cause of odorless urine