Urinalysis: Chemical and Sediment Evaluation

Vocabulary flashcards covering upper/lower urinary tract anatomy, urine collection methods, gross and chemical urinalysis, specific gravity, sediment analysis, cells, casts, crystals, and artifacts.

Pollakiuria

Frequent urination.

Polyuria

Excessive urination.

Oliguria

Decreased urine output.

Anuria

Complete lack of urine production.

Stranguria

Painful urination.

Cystocentesis

A urine collection method performed by inserting a sterile needle directly into a full bladder through the abdomen, yielding the most sterile sample.

Urochrome

A breakdown product of hemoglobin related to bile pigments that imparts the normal yellow color to urine.

Flocculent

A description of urine clarity containing particles large enough to be seen with the naked eye.

pH

An expression of the concentration of $H^+$ ions in a solution that measures the acidity or alkalinity of urine.

Proteinuria

The presence of abnormal amounts of protein in the urine, generally indicating an abnormality in the urogenital tract.

Glucosuria

The presence of glucose in the urine, occurring when blood glucose levels exceed the renal threshold ($170-180\text{ mg/dL}$ in dogs).

Ketosis

A condition resulting from excessive fat catabolism to provide energy in the presence of altered carbohydrate metabolism, spilling excess ketones into the urine.

Hematuria

The presence of intact red blood cells (RBCs) in the urine.

Hemoglobinuria

The presence of free hemoglobin in the urine, usually indicating intravascular hemolysis.

Myoglobinuria

The presence of myoglobin in the urine resulting from muscle damage, giving urine a brown or black color.

Pyuria

The presence of leukocytes (white blood cells) in the urine, indicating inflammation or infection in the urogenital tract.

Specific Gravity

The weight (or density) of a quantity of fluid as compared with an equal volume of distilled water.

Refractive Index

The ratio of the velocity of light in air as compared to the velocity of light in a solution, measured using a refractometer to determine specific gravity.

Hyaline Casts

The most common type of urinary cast, formed from protein excreted into the renal tubules, appearing faint and translucent.

Epithelial Casts

Urinary casts containing renal tubular epithelial cells, suggesting acute nephritis or degeneration of tubular epithelium.

Granular Casts

Urinary casts representing a stage of breakdown or degeneration of cellular elements within a cellular cast.

Waxy Casts

Urinary casts with sharp, almost angular borders and a dull, homogenous appearance, representing advanced degeneration of granular casts.

Squamous Epithelial Cells

The largest epithelial cells seen in urine sediment, originating from the skin or lower urinary tract and featuring large angular shapes with nuclei.

Transitional Epithelial Cells

Epithelial cells originating from the bladder or urethra, appearing round to oval with a central nucleus.

Renal Epithelial Cells

Epithelial cells originating from the kidney tubules ("tadpole cells"), appearing round to oval with a central nucleus.

Struvite Crystal

Magnesium Ammonium Phosphate ($MgNH_4PO_4$) crystals found in alkaline to neutral urine, commonly displaying a "coffin lid" morphology.

Calcium Oxalate Dihydrate

Crystals found in acid to neutral urine that appear as small squares or "envelopes".

Calcium Oxalate Monohydrate

Crystals described as "dumbbell" or "picket fence" shaped, strongly associated with ethylene glycol (antifreeze) toxicity.

Ammonium Biurate Crystals

Brown, round to irregular spiculated crystals ("thorny apple" shape) associated with liver disease and Dalmatians.

Cystine Crystals

Flat hexagonal crystals found in acid urine, associated with renal tubular dysfunction or inherited disorders in Newfoundlands.

Capillaria plica

The bladder worm of dogs and cats whose oval bi-operculate eggs are excreted in urine sediment.

Dioctophyma renale

The giant kidney worm of dogs whose eggs are passed in urine.

Urolithiasis

The presence or formation of calculi ("stones") anywhere in the urinary tract.

Lipuria

The presence of fat droplets (lipid) in the urine, appearing as spherical, highly refractile bodies of varying sizes.

Brownian Movement

The random movement of microscopic particles suspended in a liquid caused by collisions with each other, observed when evaluating bacteria in urine sediment.