108.5

what is the purpose of the microscopic examination of urine?

to detect and identify insoluble materials present in the urine

List the seven chemical parameters commonly used as markers in macroscopic screening.

Color,Clarity, Blood, Protein, Nitrite, Leukocyte esterase, glucose

List the three CLSI recommendations for urine macroscopic screening

Requested by the physician, Laboratory- specified patient population, Any abnormal physical or chemical result

What is an important step in specimen preparation to ensure an adequate urine sediment?

Fresh urine or 2-4 hours in the refrigerator, thoroughly mix specimen before putting it on the slide.

Why is 10-12 ml indicated for a urine volume to perform an accurate urine microscopic?

Reagent strips are easily immersed in this volume and capped centrifuge tubes are often calibrated to this volume.

Why is the centrifugation speed or centrifugal force (RCF) important in standardization

Produces an optimum amount of sediment with the least chance of damaging the elements,

what is the recommended RCF and time of centrifugation?

5 mins. at 400 RCF

Why is RCF a more accurate way to determine optimum speed of centrifuge?

RCF corrects for variations in the diameter of centrifuge heads, revolutions per minute does not.

What is the desired ratio of urine volume to sediment?

12:1

Why should the amount of supernatant poured off be controlled?

So, you don't lose any sediment at the bottom of the test tube

Sulfonamide crystal

dehydration, shapes include neeldes, rhombic, whetstones, sheaves of wheat, and rosettes with colors ranging from colorless to yellow brown, infection treatment

Amorphous urates

acidic urine, pink precipitate

uric acid

acidic urine, rhombode, rosettes

calcium monohydrate

acidic urine, ovoid calcium oxalate

calcium oxalate

acidic urine, envelopes

sodium urates

acidic urine, thin needles

amorphous phosphates

alkaline urine, white precipate

triple phosphate

alkaline urine, "coffin lids", colorless

ammonium biurate

alkaline urine, thorny apple phosphate, yellow brown

calcium phosphate

alkaline urine, thin prisms, flat rectangles, colorless

calcium carbonate

alkaline urine, dumbbell shape, small, colorless

Cystine crystal

abnormal, hexagonal plates, thin and thick plated, colorless, inherited cystinuria

Cholesterol crystal

abnormal, rectangular plates with notched corners, nephrotic syndrome

Tyrosine crystal

abnormal, fine, colorless to yellow needles in clumps or rosettes, positive bilirubin and seen with leucine crystals, liver disease

Leucine crystal

abnormal, yellow-brown spheres with concentric circles and radial striations, sen with tyrosine crystals, liver disease

Bilirubin crystals

abnormal, bright yellow clumps-clumped needles/granules, liver disease

Ampicillin

abnormal, bundles following refrigeration, infection treatment

radiographic

abnormal, flat plates, high specific gravity/refractometer, radiographic procedure

Give the physical, chemical and exceptions of RBC

physical: turbidity, red, chemical: + blood, + protein, exceptions: number, hemolysis

Give the physical, chemical and exceptions of WBC

physical: turbidity, chemical: + protein, +nitrite, +LE, exceptions: number, lysis

Give the physical, chemical and exceptions of epithelial cells

physical: turbidity, chemical: none, exceptions: number

Give the physical, chemical and exceptions of casts

physical: none chemical: + protein, exceptions: number

Give the physical, chemical and exceptions of bacteria

physical: turbidity chemical: pH, +nitrite, +leukocytes, exceptions: number and type

Give the physical, chemical and exceptions of crystals

physical: turbidity, color, chemical: pH, +bilirubin, exceptions: number and type

what does a kova slide stain?

nucleus

what is the 0.5% of toluidone blue stain used for?

wbc differenation and renal cells

what is acetic acid used for?

will lyse RBC

what will lipids stains do?

triglycerides and neutral fats stain orange - red; cholesterol does not stain but polarizes

what is a gram stain used for?

differentiates gram negative bacteria and gram positive; can ID bacterial casts; fixed smear

what is hansel stains used for?

preferred for urinary eosinophils

what is prussian blue used for?

hemosiderin granules(iron); stains blue

what does CytoDiagnostics urine testing monitor?

renal disease/malignancies; permanent stain

Bright-field microscopy

used for routine urinalysis

Phase-contrast microscopy

enhances visualizations of elements with low refractive indices, such as hyaline casts, mixed cellular casts

Polarizing microscopy

aids in identification of cholesterol in oval fat bodies, fatty casts, and crystals

dark-field microscopy

Aids in identification of Treponema pallidum

fluorescence microscopy

Allows visualization of naturally fluorescent microorganisms or those stained by a fluorescent dye including labeled antigens and antibodies

Interference- contrast microscopy

Produces a three-dimensional microscopy image and layer-by-layer imaging of a specimen

Which cell can be used to focus on the correct plane in a urine specimen?

epitheal cells due to size and typically present in urine

Which urine elements are reported by lower power field? And high power field?

Lpf: casts, Hpf: RBC, WBC

What are some advantages to using stain on urine sediment?

Stains the nucleus and makes it stand out, more characteristics stand out

What does birefringent property refer to in an object?

Refracts light in different dimensions; polarization microscope

List two urine elements that have birefringent properties.

crystals and fats

What is the significance of red cells in urine?

Rbc casts = urinary stasis = higher in urinary tract glomerular nephritis

Which elements may be confused with rbcs microscopically?

Yeast; look for budding yeast and look for blood on your dipstick to be present

Name and describe a clinically significant form of squamous epithelial cells. Describe the appearance of cell.

Clue cells but called from a vaginal it is bacteria that is sticking to the cytoplasm of the squamous cell

Renal tubular cells: Columnar

larger;proximal convoluted tubule

Renal tubular cells: Round, oval

smaller; distal convoluted tubule

Renal tubular cells: Cuboidal

collecting duct, never round

Renal tubular cells: 3 or more cells

renal fragment

How is the WBC and RTE cells differentiated?

Eccentric nucleus

Name three substance RTE may absorb and show up in RTE appearance.

Absorb: bilirubin, hemoglobin, lipids

At which pH do abnormal crystals precipitate?

acidic urine

Why would iatrogenic compounds precipitated in urine considered significant?

We have introduced them(iatrogenic); X-ray contrast media or medications; indicates some kidney damage because our kidneys should filter it out unless there is stasis then it will show up in the urine.

What is the significance of white cells in urine?

infection; pyelonephritis if you see wbc casts because they come from the tubules