Urine Manual Microscopic Basics Review

A set of vocabulary flashcards covering the identification and clinical significance of urinary constituents based on Dr. Joanna Ellis's lecture on manual microscopic urinalysis.

SLAPs

The competency assessments in the final year of the MLS program where students are assessed on their ability to recognize urine constituents before clinical rotation.

Standard Centrifugation for Urine

Centrifuging $10$ to $15$ mils (typically $10$ to $12$ mils) of urine at a rate of $2,000$ RPMs for approximately $5$ minutes.

Sediment and Supernatant Mixture

The portion of the sample (typically exactly $1$ mil) left in the tube after pouring off the supernatant to be mixed and viewed microscopically.

Cova System

A system used to standardize variables in urinalysis, featuring graduated centrifuge tubes, a special pipetter to hold exact supernatant amounts, and plastic slides with standardized wells.

Low Power Objective (10x)

The objective used to perform an initial scan and enumerate specific large constituents like squamous epithelial cells or casts.

High Dry Objective (40x)

The objective used for enumerating most urine constituents; oil should never be used on this or any higher objective in urinalysis.

Condenser Adjustment

Lowering the condenser to create more shadow and contrast, which is essential for seeing clear or colorless constituents like mucus and bacteria.

Red Blood Cells (RBCs)

Cells that are typically smaller than white cells, biconcave in shape, and exhibit a refractile 'blinking' effect when fine-focusing.

White Blood Cells (WBCs)

Cells that are larger than red cells with internal granularity; in the presence of $2\%$ acetic acid, their nuclei are emphasized while RBCs lyse.

Crenated Red Cells

Red cells that shrivel and form little knobs or nodules when in hypertonic or high osmo urine; often confused with white blood cells.

Ghost Cells

The appearance of red cells in dilute or hypotonic urine where they have swollen and only the edging of the cell remains visible.

Fine Focus Usage

The continuous movement of the fine focus knob used to view the three-dimensional nature of the urine and identify the concavity and refractility of constituents.

Yeast

Ovoid constituents that are insoluble in acid and characterized by the presence of 'budding' (looking like a snowman or bowling pin) or pseudohyphae.

Candida albicans

The most common type of yeast found in urinary tract infections, particularly in patients with diabetes.

Squamous Epithelial Cells

Large, flat epithelial cells typically derived from the vagina or urethra; their nucleus is approximately the size of a white blood cell.

Transitional Epithelial Cells

Round epithelial cells that are intermediate in size between squamous and renal cells, featuring a smaller nucleus than renal cells.

Renal Tubular Epithelial Cells

The smallest of the epithelial cells which have the highest N:C (nucleus to cytoplasm) ratio.

Clean Catch

A collection method used to reduce the number of squamous epithelial cells and external bacteria in a urine sample.

Bacteria

Background constituents that can be rod-shaped (bacilli) or circular (cocci); they are easily missed if the microscope light is too high or the condenser is too high.

Clue Cells

Squamous epithelial cells covered in bacteria (typically Gardnerella vaginalis) giving them a textured, raggedy-edged appearance; indicative of bacterial vaginosis.

Calcium Oxalate

Colorless, octahedral crystals that look like envelopes; they can also appear as spheres, ovals, or dumbbells and form rosettes.

Triple Phosphate

Ammonium magnesium phosphate crystals found in neutral/alkaline urine that typically look like 'coffin lids' or picture frames.

Uric Acid

Crystals found in acidic urine that occur as diamond or rhombic prisms (football shape) and are often stained yellow or red-brown by urinary pigment.

Ammonium Biurate

Yellow-brown spherical crystals with long, irregular spicules, frequently called 'thorny apples.'

Cystine

Colorless, hexagonal plates with equal sides that may resemble a spiral staircase; presence is always clinically significant (congenital cystinosis).

Tyrosine

Clinically significant fine, refractile needles that occur in sheaths or clusters, often appearing dark in the center.

Cholesterol

Crystals appearing as notched square sheets that exhibit a 'Maltese cross' pattern under polarized light.

Bilirubin Crystals

Reddish-brown or yellow-brown needles or granules that precipitate in acidic urine when bilirubin levels are high.

Tamm-Horsfall Protein

The specific mucoprotein that forms the basic matrix of all urinary casts.

Casts

Cylindrical structures with parallel sides formed in the distal and collecting tubules, usually indicating urinary stasis.

Hyaline Casts

The most common and difficult-to-see cast type; they are colorless with parallel sides and curved ends.

Waxy Casts

Highly refractile, rigid casts with blunt ends and frequent fissures or cracks; they are clinically significant indicators of chronic renal disease.

Mucus

Fine, wispy threads with squiggly, non-parallel edges that can be confused with hyaline casts.

Fibers

Highly refractile contaminants (from hair, clothing, etc.) that are typically larger than casts and do not have parallel sides or rounded ends.

Spermatozoa

Constituents with a small head and a long, thin tail; they may be non-motile in urine samples.