Clinical Pathology Final

What types of items go into a biohazard bag?

Contaminated stuff with bodily fluids

What types of items go into a sharps container?

Glass, needles, slides

What is a centrifuge used for in the lab?

Separates substances with different densities in a solution

Could you tell me how to safely load a centrifuge machine?

Machine must be balanced by using tubes of equal size and weight

What could happen if a centrifuge machine is not loaded properly?

The machine could be damaged, the operator could be injured, and the diagnostic sample could be lost

What is the supernatant?

Top, liquid portion

What is the sediment?

Bottom, solid portion

What happens if you spin samples too fast?

Cells rupture and morphological features destroyed

What happens if you spin samples too slowly?

Incomplete separation or concentration of specimen

What is the incubator used for?

Variety of microbiological tests (i.e culture and sensitivity testing)

At what temperature should you set this incubator for incubation of most samples?

37 C/98.6 F

How should culture plates be placed inside the incubator?

Inverted (prevent condensation)

Why is this placement of plates inside the incubator important?

Because condensation alters growth of colonies which make isolation and identification difficult

How high can you stack these culture plates for appropriate incubation temperature to be reached for all plates?

No more than 4

What is a refractometer used for?

To measure concentration of solids dissolved in a liquid that do not separate when centrifuged

What two measurements can you obtain using this instrument?

USG (specific gravity of urine) or PP (total plasma protein concentration)/ TS (total serum protein concentration – total solids)

What should you do if it appears blurry when you look through the eyepiece?

Clean prism surface and cover plate

How should you properly clean the instrument prior to the next use?

Use distilled water and a soft tissue/cloth to clean and then wipe dry before next use

What is the specific gravity of distilled water?

1,000

Where do you read your measurement when using this instrument?

At the light-dark interface. (SG for USG and PROTEIN for PP/TS)

What unit of measurement is used for Urine Specific Gravity?

No units of measurement (PP/TS measured in g/dl)

You can use oil for oil immersion with which lens or lenses of the microscope?

ONLY oil immersion lens - 100x

What is the proper method of removal to avoid accidental damage to other lenses?

Lower stage and clean oil immersion lens last

If I asked you ‘What is quality control?’ could you tell me?

Measure of precision (how well measurement system reproduces the same result over time)

What is a quality control assay?

Samples inserted into testing process and treated as through they were patient samples. Used to validate the precision of the test method and equipment used to produce results

Can you give me examples of times when a quality control assay should be tested?

▪ Beginning of each shift change
▪ After instrument is serviced
▪ When reagent lots are changed
▪ After calibration
▪ When patient results seem inappropriate

Why is the time of sample collection for urine important?

Because characteristics of the urine will be altered due to bacteria, concentration, temperature, pH change.

What are the three basic methods of urine sample collection?

Cystocentesis, catheterization, and free catch

Which method is considered to be sterile and is most appropriate for microbiological testing?

Cystocentesis

If a sample is ‘voided’, what does this mean?

Free-catch or manual bladder expression

If a urine sample has been refrigerated prior to testing, how should you prepare that sample for testing when you are ready to evaluate it?

Allow sample to set out for 10-15 mins (returning to
room temp), gently invert sample, and then perform UA as normal

Urine samples are usable for how long after sample collection and only under which condition(s)?

Up to 12 hours only if they are refrigerated

Tissues and fluids are usable for cytological testing for how long after sample collection and under which conditions?

Within 24 hours. Solid tissue must be placed in preservative immediately. Measure SG, Centrifuge fluids, prepare at least two slides (one with in-house stain and one unstained). Fluids placed in purple top tubes and refrigerated. NEVER freeze

If you collect a fluid cytology sample, why is centrifugation important prior to storing for later testing?

It concentrates and preserves the cellular components

If you are trying to collect a scraping from a dry, crusty location, what can you do to make sure that the sample transfers onto the slide successfully?

Apply mineral oil to blade prior to scraping

Which sites work better for sample collection when using swabs?

Exudates and moist surfaces

When would using a cotton-tipped swab be appropriate for microbiological sample collection?

If the sample is to be used to inoculate the culture media IMMEDIATELY

If there is going to be a delay between sample collection and testing, how should you collect the sample for microbiological testing?

Collect using a culturettes

Which urine sample collection method is BEST for performing a UA?

Cystocentesis

What is the purpose of performing a UA?

to determine basic kidney function (physical, chemical,
cellular characteristics)

What time of day is BEST for urine sample collection? Why?

Urine is least affected by diet giving best chance at measuring characteristics accurately. Urine is more concentrated and pH more acidic which preserves cellular characteristics

What are two methods we discussed in lab which are appropriate for preparing slides for evaluating urine sediment?

Wet mount or dry mount (line smear preparation)

What are we evaluating when we prepare a slide for cytology testing?

Cells shed from body surfaces (type, number, appearance) and to differentiate between inflammation and neoplasia

How would you prepare slides if you used these sample collection methods?

Swabs: ensure collection site is moist or apply sterile saline to swab, label slide, and roll swab
length wise down slide (rolling method)

When is it necessary to heat fix a cytology slide?

Melting ear wax or performing a gram stain

What is the purpose of performing microbiological testing?

To identify bacterial organisms and determine susceptibility to various drugs for treatment

Generally how long are samples incubated for microbiological testing?

24-48 hours

Under what category are most veterinary diagnostic samples classified for shipping?

Category B (biological substance)

What types of samples would be classified under Category A?

infectious substance in form capable of causing permanent disability or life-threatening/fatal diseases (ex. Foreign animal diseases – FADs, zoonotic diseases, reportable diseases, live animals, culture media of LIVE bacterial or viral organisms)

What does the shipping label for a Category B Biological Substance look like?

What is the number that is on this shipping label that designates it as a Category B Biological Substance?

UN3373

If you are shipping a liquid, where should the absorptive layer of packaging be placed?

Between the primary and secondary packaging

Can you provide some examples of primary containers?

Plastic or glass tubes, plastic cups with screw or snap-on lids

If you are shipping more than one container, slide, or test tube, what must you be sure to do with these samples when packaging to make sure all contents arrive safely?

Each sample has its OWN primary packaging properly cushioned to prevent breakage or leakage. Secondary packaging can be collective.

What is a urinalysis (UA)?

laboratory examination of urine sample to determine basic kidney function

What are the three basic parts of a UA?

physical, chemical, and sedimentary characteristics

How much urine is needed to perform a UA?

5 ml (a teaspoon)

Can you name the components evaluated for physical characteristics of urine on UA?

volume, color, odor, transparency/clarity, USG

What is considered normal for each of these components for a sample of urine from a healthy animal?

Yellow color, ammonia-like odor, clear transparency, USG 1.015-1.035 (varies by species)

Urine Specific Gravity would fall under which basic part of the UA?

physical characteristics

If you say that the urine is clear, which physical characteristic of urine are you describing?

Transparency

Which characteristic of urine has the greatest effect on urine clarity?

Amount of sediment present

What do the following terms indicate when observed on UA?Cloudy = newsprint is blurry
Turbid = newsprint completely block from view Flocculent = visible particles present

Levels of transparency/clarity

If urine has a strong ammonia odor, what should you suspect to find on your urine sediment evaluation?

Increased numbers of bacteria

If urine has a distinctive fruity odor, what should you expect to see on your urine chemical evaluation on UA?

ketones

Hyperstenuria:

higher than glomerular filtrate (above 1.012) = concentrated urine

Hyposthenuria:

lower than glomerular filtrate (below 1.008) = dilute urine

Isosthenuria:

equal to glomerular filtrate (1.008-1.012). no change in the glomerulus filtration from beginning of the glomerulus until it reaches the collecting ducts. NOT absorbing or secreting. Significant kidney loss

Knowthespecificgravityrangewhichisdefinedasisosthenuria.

1.008-1.012

Why is this USG range significant?

Indicates hydration status and ability of kidneys to concentrate urine

Cattle average USG:

1.015

Dog average USG:

1.025

Cat average USG:

1.030

Sheep average USG:

1.030

Horse average USG:

1.035

If I measure the USG, what info does this provide about my patient?

Hydration status and ability to concentrate urine

What are the expected normal values for a healthy animal regarding the following:

Glucose:

only if filtration rate exceeds resorption rate

What are the expected normal values for a healthy animal regarding the following:

Protein:

none to trace

What are the expected normal values for a healthy animal regarding the following:

Ketones:

none

What are the expected normal values for a healthy animal regarding the following:

Bile pigments:

none; trace amounts in dogs and cattle

What are the expected normal values for a healthy animal regarding the following:

RBCs:

none to trace

What are the expected normal values for a healthy animal regarding the following:

WBCs:

NOT evaluated using strips bc UNRELIABLE

What test is used to confirm the presence of protein in urine?

SSA (sulfosalicylic acid) turbidity test

What test is used to confirm the presence of sugars in the urine?

Clinitest reagent tablets

What test is used to confirm the presence of bile pigments in the urine?

Icototest tablets

If you detect WBCs in urine on your chemical analysis, what should you do to confirm this?

Perform microscopic evaluation

Why is the pH of urine important clinically?

Too acidic or too alkaline crystals form, can be
manipulated to dissolve or prevent crystal formation and to inhibit bacterial growth

What are the normal or expected findings for the following in urine sediment?

RBCs:

increased in catheterization and cystocentesis

What are the normal or expected findings for the following in urine sediment?

WBCs:

increased in voided samples

What are the normal or expected findings for the following in urine sediment?


Epithelial cells:

increased in catheterization

What are the normal or expected findings for the following in urine sediment?


Bacteria:

higher in voided samples

Which urine sample collection method contains the most sediment in an otherwise healthy
animal?

Voided

What is one quick way you can differentiate between hematuria and
hemoglobinuria/myoglobinuria on UA?

centrifugation

What changes would appear if hematuria were present in the urine sample?

Supernatant = loses red color, Sediment = red

What changes would appear if hemoglobinuria/myoglobinuria were present in the urine sample?

BOTH supernatant and sediment = red

Hyaline cast:

clear, colorless, mostly transparent, rounded ends

Waxy cast:

wider than hyaline cast with squared ends and a dull, colorless, gray appearance. Indicate severe, chronic degeneration of the renal tubules

Granular cast:

contain degenerated epithelial cells, RBCs, or WBCs (most common in animals)

Struvite crystal:

“coffin lids”, 6-8 sided prisms with tapering sides and ends

Calcium carbonate crystal:

“dumbbell shape” orround with many lines radiating from center