Microscopic Examination of Urine and Pregnancy Testing

Comprehensive vocabulary flashcards covering urine sediment examination, specific elements (cells, casts, crystals), and pregnancy testing methodologies based on lab lecture notes.

Microscopic Screening

A diagnostic tool for the detection and evaluation of renal and urinary tract disorders and other systemic diseases through examination of urine sediment.

Centrifugation Parameters

Performed for a duration of $5$ minutes at a relative centrifugal force (RCF) of $400$. The centrifuge must be balanced and regularly calibrated.

Specimen Volume

Standard volume is between $10$ and $15\,mL$, with an average of $12\,mL$ of urine placed in a tube.

Glass-slide method

A sediment examination procedure using $20\mu L$ of sediment covered by a $22 \times 22\,mm$ coverslip.

Organized Specimen Elements

Constituents of higher clinical importance found in urine sediment, including casts, pus cells, RBCs, epithelial cells, spermatozoa, bacteria, and parasites.

Red Blood Cells (RBCs)

Smooth, biconcave disks about $7\mu m$ in diameter and $2\mu m$ thick that do not contain nuclei.

Ghost cells

Red blood cells that swell up and lyse in hypotonic (dilute and alkaline) urine.

Crenated RBCs

Red blood cells that shrink in hypertonic (concentrated) urine.

White Blood Cells (WBCs)

Primarily neutrophils with a diameter of $10-12\mu m$; normal urine may contain $2-3$ cells per hpf.

Glitter cells

Nonpathologic neutrophils that occur in hypotonic urine, exhibit Brownian movement, swell, and have granules that sparkle.

Tubular Epithelial Cells (RTE cells)

Cells slightly larger than leukocytes with a large round nucleus; their presence indicates necrosis of the renal tubules.

Transitional Epithelial Cells (Urothelial)

Cells two to four times as large as white cells, pear-shaped or round, containing two nuclei; they often appear following invasive urologic procedures.

Squamous Epithelial Cells

Large, flat, irregular-shaped cells with abundant cytoplasm and small central nuclei; the most abundant epithelial type found in urine.

Clue cells

Squamous epithelial cells used to identify vaginal infection by Gardnerella Vaginalis.

Spermatozoa

Elements with oval heads and long flagellated tails; significant in cases of male infertility or retrograde ejaculation and toxic in urine.

Mucus Threads

Protein (CHON) materials appearing as thread-like structures with a low refractive index; they have no clinical significance.

Yeast Cells

Small refractive oval structures, such as C. albicans, which may contain a bud; increased in diabetics or those with vaginal moniliasis.

Tamm-Horsfall Protein

A mucoprotein secreted by the renal tubules that is believed to form the basic matrix of all casts.

Hyaline Casts

Colorless, homogenous, transparent casts with rounded ends; seen in normal urine or increased in mild renal disease.

Red Cell Casts

Always pathogenic casts that are usually diagnostic of glomerular disease, such as acute glomerulonephritis.

Waxy Casts

Casts with a high refractive index and a yellow-grey or colorless homogenous appearance resulting from the degeneration of granular casts.

Fatty Casts

Casts formed by incorporated free fat droplets or oval fat bodies, frequently seen in nephrotic syndrome.

Cystine Crystals

Colorless, hexagonal plates with equal or unequal sides found in acid urine; indicate congenital cystinosis or cystinuria.

Tyrosine Crystals

Fine, refractile needles occurring in clusters in acid urine; associated with severe liver disease or tyrosinosis.

Leucine Crystals

Yellow or brown, oily, highly refractile spheroids found in acid urine; associated with severe hepatitis or acute yellow atrophy.

Triple Phosphate Crystals

Colorless prisms with three to six sides resembling "coffin lids"; normally found in alkaline or neutral urine.

Uric Acid Crystals

Diamond, rhombic, or rosette forms stained yellow or red-brown by urinary pigments; associated with gout or chronic nephritis.

Calcium Oxalate Crystals

Colorless, envelope-shaped, oval, sphere, or biconcave disks (dumb-bell shape) found in acid or neutral urine.

Amorphous Urates

Non-crystalline pink or brownish tan granules found in acid or neutral urine; they have no clinical significance.

Human Chorionic Gonadotropin (HCG)

A glycoprotein hormone secreted by the trophoblast of the developing embryo; increases rapidly in urine or serum during early pregnancy.

Immunochromatography

The principle used in PT (Rapid Test Kits) for the qualitative, visual detection of HCG.

PT-Agglutination Inhibition

A methodology where a positive result is indicated by no agglutination when the patient specimen neutralizes anti-HCG antibodies.