Microscopic Analysis of Urine & Body Fluids Flashcards

Vocabulary practice flashcards generated from lecture notes covering microscopic urinalysis, sediment staining, microscopy techniques, urinary cells, casts, crystals, and artifacts.

Addis Count

The first procedure to standardize the quantitation of formed elements in urine using a hemocytometer, utilizing a $12\text{-hour}$ urine specimen preserved in formalin.

Sternheimer-Malbin Stain

A supravital stain consisting of crystal violet and safranin that delineates the structure and contrasting colors of the nucleus and cytoplasm to identify WBCs, epithelial cells, and casts.

Toluidine Blue ($0.5\%$)

A metachromatic supravital stain that enhances nuclear detail to differentiate white blood cells (WBCs) from renal tubular epithelial (RTE) cells.

Hansel Stain

A urinary stain consisting of methylene blue and Eosin Y used specifically to stain eosinophilic granules for identifying urinary eosinophils.

Prussian Blue Stain

A chemical stain that reacts with structures containing iron to identify yellow-brown granules of hemosiderin in urinary cells and casts.

Cytodiagnostic Urinalysis

A specialized procedure involving a $10:1$ concentration of a first morning urine specimen followed by cytocentrifugation and Papanicolaou staining, useful in diagnosing early renal allograft rejection and differential diagnosis of renal disease.

Phase Contrast Microscopy

A microscopic technique that converts variations in a specimen's refractive index into variations in light intensity, ideal for visualizing low-refractive index elements such as hyaline casts, mixed cellular casts, mucous threads, and Trichomonas.

Polarizing Microscopy

A microscopy technique employing crossed polarizing filters to detect doubly refractile (birefringent) substances, such as cholesterol in oval fat bodies, fatty casts, and crystals.

Dark Field Microscopy

A microscopy technique utilizing a dark-field condenser with an opaque disk to illuminate specimens light against a black background, aiding in the identification of spirochetes like Treponema pallidum.

Köhler Illumination

A type of microscopic illumination where a lamp condenser focuses the image of the light source onto the front focal plane of the substage condenser.

Parfocal

A term describing microscope objective lenses that remain in focus when switching from one objective to another of differing magnification.

Parcenter

A term describing microscope objective lenses that retain the same field of view when switching between objectives of differing magnification.

Ghost Cells

Faint, colorless, swollen RBC circles formed in hypotonic or alkaline urine as hemoglobin dissolves out of the erythrocytes.

Echinocytes

Crenated, irregularly shaped red blood cells appearing as small, rough cells with crinkled edges in hypersthenuric or concentrated urine.

Dysmorphic RBCs

Fragmented or distorted red blood cells (mainly acanthocytes) varying in size with membrane protrusions, characteristic of glomerular bleeding.

Pyuria

The presence of an increased number of white blood cells in urine (leukocyturia), indicative of bacterial urinary tract infection (UTI), interstitial nephritis, or SLE.

Glitter Cells

Large white blood cells found in hypotonic urine that exhibit a sparkling appearance from Brownian movement of granules, staining light blue with Sternheimer-Malbin stain.

Myelin Forms

Finger-like or wormlike projections protruding from the surface of breakdown WBCs due to cell membrane degradation.

Clue Cells

Pathologic squamous epithelial cells covered extensively with Gardnerella vaginalis coccobacilli, giving the cell a granular, irregular border.

Transitional Epithelial Cells

Epithelial cells originating from the lining of the renal pelvis, calyces, ureters, bladder, and male urethra, appearing spherical, polyhedral, or caudate with central nuclei.

Renal Tubular Epithelial (RTE) Cells

Epithelial cells originating from renal tubules whose presence in elevated numbers ($> 2\,\text{per HPF}$) indicates renal tubular injury or necrosis.

Bubble Cells

Renal tubular epithelial cells containing large, nonlipid-filled vacuoles formed by dilated endoplasmic reticulum prior to cell death in acute tubular necrosis.

Oval Fat Bodies

Highly refractile, lipid-containing renal tubular epithelial cells or macrophages that produce a characteristic Maltese cross pattern under polarized light.

Uromodulin

A mucoprotein (Tamm-Horsfall protein) secreted by RTE cells that serves as the major constituent and matrix for urinary casts and mucus.

Cylindruria

The clinical term denoting the presence of urinary casts in the urine sediment.

Cylindroids

Structures formed at the ascending loop of Henle and DCT that feature a tapered tail at one end, representing incomplete cast formation or cast disintegration.

Hyaline Cast

The most common urinary cast, composed almost entirely of uromodulin; colorless with a low refractive index and rounded ends.

RBC Cast

An orange-red urinary cast containing enmeshed red blood cells, indicating nephron bleeding specifically associated with glomerulonephritis.

WBC Cast

A cellular cast containing leukocytes, serving as a key marker to distinguish upper UTI (pyelonephritis) from lower UTI (cystitis).

Waxy Cast

A highly refractive, brittle cast with jagged ends and side notches, indicating extreme urine stasis and chronic renal failure.

Broad Cast

A wide cast formed in distended tubules or collecting ducts during severe urine stasis, referred to as a 'renal failure cast.'

Rous Test

A diagnostic test using a potassium ferricyanide–HCl solution to confirm the presence of hemosiderin granules in urine sediment via a blue Prussian reaction.

Amorphous Urates

Normal acidic urine crystals appearing as yellow-brown or brick-dust granules that form a pink sediment due to uroerythrin.

Calcium Oxalate Crystals

Acidic urine crystals found as dihydrate envelope/pyramidal forms or monohydrate oval/dumbbell forms, increased in ethylene glycol poisoning.

Triple Phosphate Crystals

Normal alkaline urine crystals composed of magnesium ammonium phosphate, classically appearing as colorless prisms with a 'coffin lid' or feathery fern-leaf shape.

Ammonium Biurate Crystals

Yellow-brown alkaline urine crystals shaped like 'thorny apples' (spicule-covered spheres), found in old specimens containing urea-splitting bacteria.

Cystine Crystals

Abnormal acidic urine crystals that form colorless hexagonal plates, diagnostic of cystinuria.

Cholesterol Crystals

Abnormal flat, rectangular plates with notched corners ('staircase pattern'), associated with nephrotic syndrome and lipiduria.

Leucine Crystals

Abnormal yellow-brown spheres displaying concentric circles and radial striations, seen in severe liver disease.

Tyrosine Crystals

Abnormal needle-like crystals occurring in silky colorless-to-yellow sheaves or rosettes, associated with severe liver disease.

Sulfonamide Crystals

Iatrogenic crystals appearing as sheaves of wheat, rosettes, or needles in acidic urine; confirmed positive via a yellow color in the lignin test using $25\%\,\text{HCl}$.

Starch Granules

Urinary sediment artifacts appearing as spheres with dimpled centers that show a pseudo-Maltese cross under polarizing microscopy.

Compound Microscope Diagram

An anatomical diagram detailing the component parts of a clinical compound microscope divided into the Lens System, Illumination System, and Body.

Fatty Cast Birefringence

Pathognomonic fatty cast for high urinary protein nephrotic syndrome displaying a Maltese cross pattern under polarized light.