Microscopic Examination of Urine Sediment

Macroscopic urine screening

Initial assessment of urine's physical and chemical properties.

Sediment examination

Analysis of urine sediment for diagnostic purposes.

Centrifugation

Process of spinning urine to separate components.

Sternheimer-Malbin stain

Stain used to enhance cellular detail in urine.

Acetic acid stain

Stain that highlights nuclear detail in cells.

Toluidine blue stain

Stain used for identifying cellular structures.

Sudan III stain

Stain for detecting fat in urine sediment.

Gram stain

Stain to differentiate bacterial types in urine.

Hansel stain

Stain used for identifying eosinophils in urine.

Prussian blue stain

Stain for detecting iron deposits in urine.

Bright-field microscopy

Standard microscopy for viewing urine samples.

Phase-contrast microscopy

Technique enhancing contrast in transparent specimens.

Polarizing microscopy

Used to identify crystalline structures in urine.

Fluorescence microscopy

Technique using fluorescence for specimen examination.

Interference-contrast microscopy

Enhances contrast for transparent specimens without staining.

Red blood cells (RBCs) significance

Indicates potential bleeding or injury in urinary tract.

White blood cells (WBCs) significance

Suggests infection or inflammation in urinary tract.

Epithelial cells in urine

Indicates renal or urinary tract health status.

Oval fat bodies

Sign of lipiduria, often associated with nephrotic syndrome.

Cast formation process

Occurs when proteins precipitate in renal tubules.

Types of casts

Includes hyaline, RBC, WBC, granular, waxy, fatty, broad.

Normal crystals in acidic urine

Includes uric acid and calcium oxalate crystals.

Normal crystals in alkaline urine

Includes struvite and calcium phosphate crystals.

Cystine crystals

Indicates cystinuria, a genetic disorder.

Cholesterol crystals

Associated with nephrotic syndrome and lipid metabolism.

Leucine crystals

Indicates maple syrup urine disease.

Tyrosine crystals

Associated with liver disease and metabolic disorders.

Bilirubin crystals

Indicates liver dysfunction or hemolysis.

Sulfonamide crystals

Result from sulfonamide medications in urine.

Radiographic dye crystals

Indicates recent imaging studies using contrast.

Ampicillin crystals

Result from ampicillin therapy in urine.

Artifacts in sediment

Non-biological particles mistaken for sediment constituents.

Correlate urinalysis results

Link physical, chemical, and microscopic findings.

Microscopic Examination

Analyzing urinary sediment under a microscope.

Insoluble Substances

Solid elements found in urinary sediment.

Red Blood Cells (RBCs)

Cells indicating potential bleeding in urine.

White Blood Cells (WBCs)

Cells indicating infection or inflammation.

Epithelial Cells

Cells lining urinary tract, indicating potential damage.

Casts

Molds of renal tubules found in urine.

Bacteria

Microorganisms indicating possible urinary tract infection.

Yeast

Fungi that may indicate infection in urine.

Parasites

Organisms that can infect urinary system.

Mucus

Viscous substance that may appear in urine.

Spermatozoa

Male reproductive cells found in urine.

Crystals

Solid formations indicating metabolic disorders.

Artifacts

Debris that can obscure true sediment analysis.

Standardization

Consistency in procedures for accurate results.

Sediment Preparation

Process of preparing urine for microscopic analysis.

Specimen Volume

Amount of urine required for analysis.

Centrifugation

Process to separate sediment from urine.

Relative Centrifugal Force (RCF)

Measurement correcting for centrifuge head diameter.

Sediment Volume

Amount of sediment analyzed from urine sample.

Commercial Systems

Standardized systems improving urine microscopic analysis.

Glass Slide Method

Technique for examining urine sediment on slides.

Low Power Examination

Initial scanning at 10× magnification.

High Power Examination

Detailed analysis at 40× magnification.

Reporting Examination

Documenting findings from microscopic analysis.

Elements per mL

Concentration of formed elements in urine.

Sediment Appearance

Visual characteristics of sediment under microscope.

Sediment Stains

Dyes enhancing visibility of sediment structures.

Supravital Stains

Stains used to visualize living cells.

Sternheimer-Malbin Stain

Common supravital stain using crystal violet.

Quantitative Reporting

Expressing results in measurable terms.

Contamination

Unwanted substances affecting sediment analysis.

Toluidine Blue

0.5% solution enhancing nuclear detail visualization.

Acetic Acid

Enhances WBCs; lyses RBCs in urine samples.

Lipid Stains

Identify free fat droplets and lipid casts.

Oil Red O

Stains triglycerides and neutral fats orange-red.

Sudan III

Another stain for triglycerides in urine.

Gram Stain

Differentiates gram-positive (blue) and gram-negative (red) bacteria.

Hansel Stain

Preferred for identifying urinary eosinophils.

Methylene Blue

Component of Hansel stain for eosinophils.

Eosin Y

Another component of Hansel stain.

Prussian Blue Stain

Stains hemosiderin granules blue in hemoglobinuria.

Cytodiagnostic Urine Testing

Detects renal diseases and malignancies via cytology.

Papanicolaou Stain

Used in cytodiagnostic testing for cellular inclusions.

Bright-field Microscopy

Most common microscopy type in urinalysis.

Phase Contrast Microscopy

Enhances contrast based on object thickness and refractive index.

Polarizing Microscopy

Identifies crystals and lipids using polarized light.

Köhler Illumination

Provides optimal viewing of illuminated field.

Compound Microscope

Two-lens system used for magnifying specimens.

Oculars

Eyepieces in a microscope for viewing specimens.

Objectives

Lenses near the specimen for magnification.

Coarse Focus

Initial focusing knob for large adjustments.

Fine Focus

Sharpens image after changing magnification.

Numerical Aperture

Indicates light-gathering ability of microscope objectives.

Parfocal

Allows minimal adjustment when switching objectives.

Mechanical Stage

Platform for holding slides in a microscope.

Field of View

Diameter of visible area through oculars.

Rheostat

Regulates light intensity in the microscope.

Condenser

Focuses light onto the specimen in microscopy.

Light Source

Provides illumination for microscopic examination.

Crossed Configuration

Polarizing filters set to identify crystals.

Birefringent Crystals

Crystals that exhibit different refractive indices.

Toluidine Blue Solution

0.5% solution enhancing nuclear detail in cells.

Lipid Stains

Identify lipids; stains include Oil Red O, Sudan III.

Triglycerides Staining

Stains orange-red; indicates presence of fats.

Hansel Stain

Preferred for urinary eosinophils; uses methylene blue.

Prussian Blue Stain

Stains hemosiderin granules blue; indicates hemoglobinuria.

Cytodiagnostic Urine Testing

Detects renal disease; uses cytocentrifugation for slides.