PATHOLOGY TEST BANK 2420
MIDTERM EXAM QUESTIONS WITH
COMPLETE SOLUTIONS
How are stool samples collected? - Answer-Stool Collection:
Plastic container
What possible tests can be performed on stool sample? - Answer-Clinical Chemistry -
Stool Sample Tests:
Blood
Ova
Parasites
What other body fluids can be collected for clinical chemistry examination? - Answer-
Spinal fluid
Pleural fluid
Peritoneal fluid
Joint aspirate
Bone marrow
What are the different types of cytopathology samples? - Answer-Exfoliative -
Spontaneous (i.e. spontaneously produced by the patient).
Exfoliative - Mechanical (i.e. intervention required to obtain cells).
Interventional
What category of cytopathology sample includes pleural or peritoneal fluid? - Answer-
Spontaneous exfoliative (spontaneously produced by patient).
What category of cytopathology sample includes sputum? - Answer-Spontaneous
exfoliative (spontaneously produced by patient).
What category of cytopathology sample includes urine? - Answer-Spontaneous
exfoliative (spontaneously produced by patient).
What category of cytopathology sample includes cervical papsmear? - Answer-
Mechanical exfoliative (intervention required to obtain cells)
What category of cytopathology sample includes bronchial brushings? - Answer-
Mechanical exfoliative (intervention required to obtain cells)
,What category of cytopathology sample includes fine needle aspiration (such as of a
lymph node or thyroid)? - Answer-Interventional
What types of samples are collected in surgical pathology? - Answer-Biopsies and
surgical resections
What sample assessment techniques are used in pathology? - Answer-Gross
examination (naked eye)
Microscopic examination (light microscopy to look at cellular morphology)
Electron microscopy (helps identify changes in organelles)
Ancillary tests:
- Immunohistochemistry (specific proteins)
- Special histochemical stains (microorganisms, specific tissues, pigment)
- Molecular pathology (genetic make up, DNA or RNA of tissue)
Provide some examples of molecular pathology tests. - Answer-Constitutional genetic
disorders
Metabolic disorders
Hereditory cancer panels/genetic predisposition to cancer
Solid tumour testing to determine treatment options
How do you create a specimen slide? Include all 6 steps. - Answer-1. Tissue cut from
specimen
2. Place tissue sample in cassette and process
3. Embed tissue in wax
4. Cut on microtome into very thin sections
5. Place/mount to slide
6. Stain
Biopsy (define) - Answer-tissue removed from the body for examination
Describe the journey of a biopsy (11 steps). - Answer-1. Biopsy samples booked in and
prioritized
2. Larger, more complex samples are delt with by consultants
3. Smaller tissue samples (like biopsies) are cut up into smaller specimens
4. Processing; all water content removed from tissue making it rigid
5. Hot wax poured over the tissue to support it, cooled, hardened (embeds and
preserves tissue)
6. Wax block sliced into very thin slices (~3 microns)
7. Slices put onto slides
8. Slides dyed with simple staining process so cells are visible under microscope
9. Quality control to make sure process is accurate
10. Consultant looks at samples and makes diagnosis
,11. General practitioner communicates the pathology results to the patient
What is order of draw? - Answer-Ensure collected blood samples are placed in the
correct tube.
Each tube has specific additives to make the specimen stable for certain analytes.
Must be followed so that there is no cross contamination between additives.
How should blood serum be collected? - Answer-Serum is the most common
component of blood tested in lab.
Use a red top tube.
Red contains NO additive, NO gel and NO anticoagulant.
Blood will clot in this tube (about 30 minutes)
Use gold, SST (Serum separator tube).
Separates cells from serum without clotting.
How would blood plasma be collected? - Answer-Blood plasma is the next most
common blood component tested in lab.
Use green top tube.
Contains heparain anticoagulant.
Benefits: can be processed quicker, does not require clotting before centrifuge.
Requires a smaller sample volume.
Use lavender top tube.
Contain EDTA to preserve blood cell morphology, inhibits clotting by binding Ca.
Good for hematology tests (eg. complete blood count).
Bad for: tests for divalent elements like Ca, Mg, or enzymes that require those ions as
cofactors (g. those used in clotting cascade)
Most (about 66%) of lab errors occur in the preanalytical phase. List
examples/opportunities for preanalytical error. - Answer-Incorrect sample type
Incorrect order of draw
Underfilled tubes
Tubes not mixed properly after collection
Sample hemolysis
Extreme temperature exposure/storage conditions (may affect analyte stability)
Delayed transportation
Time from collection to processing or analysis
Accuracy of lab tests (Define) - Answer-Ability of data, measurements or results to
match the "true" value
, Precision of lab tests (define) - Answer-How close the data, measurements or results
are to each other, working as a measure of the spread of data from the average
In terms of accuracy and precision, what are the best and worst lab tests? - Answer-
Best lab tests have high accuracy and high precision
Worst lab tests have low accuracy and low precision
What is the decision threshold line? - Answer-Lab tests are often used to confirm (rule
in) or exclude (rule out) a disease.
Decision threshold line is the cutoff value for deciding
Compare specificity vs sensitivity of lab tests. - Answer-Specific:
Considers Non-Diseased population and describes absence of disease.
A specific tests gives negative results in non-diseased subjects.
High true negative and low false positive.
Sensitive:
Considers Diseased population and describes presence of disease.
A sensitive test gives positive results in diseased subjects.
Low false negative and high true positive.
How do you measure specificity - Answer-TN / (TN+FP)
How do you measure sensitivity - Answer-TP / (TP+FN)
What is prevalence? - Answer-% of patients that have the disease that are being tested
What is a ROC curve? - Answer-Receiver Operating Characteristic curve
plots the false positive rate (1-specificity) against the true positive rate (sensitivity)
Several decision thresholds are selected, sensitivities and specificities are calculated
then plotted
How do you determine the better test from an ROC curve? - Answer-The curve with the
greater area below the curve is the better test.
What is laboratory stewardship? - Answer-The appropriate utilization of lab tests which
encompasses:
Correctly ordering tests
correctly retrieving tests
correctly interpreting tests
MIDTERM EXAM QUESTIONS WITH
COMPLETE SOLUTIONS
How are stool samples collected? - Answer-Stool Collection:
Plastic container
What possible tests can be performed on stool sample? - Answer-Clinical Chemistry -
Stool Sample Tests:
Blood
Ova
Parasites
What other body fluids can be collected for clinical chemistry examination? - Answer-
Spinal fluid
Pleural fluid
Peritoneal fluid
Joint aspirate
Bone marrow
What are the different types of cytopathology samples? - Answer-Exfoliative -
Spontaneous (i.e. spontaneously produced by the patient).
Exfoliative - Mechanical (i.e. intervention required to obtain cells).
Interventional
What category of cytopathology sample includes pleural or peritoneal fluid? - Answer-
Spontaneous exfoliative (spontaneously produced by patient).
What category of cytopathology sample includes sputum? - Answer-Spontaneous
exfoliative (spontaneously produced by patient).
What category of cytopathology sample includes urine? - Answer-Spontaneous
exfoliative (spontaneously produced by patient).
What category of cytopathology sample includes cervical papsmear? - Answer-
Mechanical exfoliative (intervention required to obtain cells)
What category of cytopathology sample includes bronchial brushings? - Answer-
Mechanical exfoliative (intervention required to obtain cells)
,What category of cytopathology sample includes fine needle aspiration (such as of a
lymph node or thyroid)? - Answer-Interventional
What types of samples are collected in surgical pathology? - Answer-Biopsies and
surgical resections
What sample assessment techniques are used in pathology? - Answer-Gross
examination (naked eye)
Microscopic examination (light microscopy to look at cellular morphology)
Electron microscopy (helps identify changes in organelles)
Ancillary tests:
- Immunohistochemistry (specific proteins)
- Special histochemical stains (microorganisms, specific tissues, pigment)
- Molecular pathology (genetic make up, DNA or RNA of tissue)
Provide some examples of molecular pathology tests. - Answer-Constitutional genetic
disorders
Metabolic disorders
Hereditory cancer panels/genetic predisposition to cancer
Solid tumour testing to determine treatment options
How do you create a specimen slide? Include all 6 steps. - Answer-1. Tissue cut from
specimen
2. Place tissue sample in cassette and process
3. Embed tissue in wax
4. Cut on microtome into very thin sections
5. Place/mount to slide
6. Stain
Biopsy (define) - Answer-tissue removed from the body for examination
Describe the journey of a biopsy (11 steps). - Answer-1. Biopsy samples booked in and
prioritized
2. Larger, more complex samples are delt with by consultants
3. Smaller tissue samples (like biopsies) are cut up into smaller specimens
4. Processing; all water content removed from tissue making it rigid
5. Hot wax poured over the tissue to support it, cooled, hardened (embeds and
preserves tissue)
6. Wax block sliced into very thin slices (~3 microns)
7. Slices put onto slides
8. Slides dyed with simple staining process so cells are visible under microscope
9. Quality control to make sure process is accurate
10. Consultant looks at samples and makes diagnosis
,11. General practitioner communicates the pathology results to the patient
What is order of draw? - Answer-Ensure collected blood samples are placed in the
correct tube.
Each tube has specific additives to make the specimen stable for certain analytes.
Must be followed so that there is no cross contamination between additives.
How should blood serum be collected? - Answer-Serum is the most common
component of blood tested in lab.
Use a red top tube.
Red contains NO additive, NO gel and NO anticoagulant.
Blood will clot in this tube (about 30 minutes)
Use gold, SST (Serum separator tube).
Separates cells from serum without clotting.
How would blood plasma be collected? - Answer-Blood plasma is the next most
common blood component tested in lab.
Use green top tube.
Contains heparain anticoagulant.
Benefits: can be processed quicker, does not require clotting before centrifuge.
Requires a smaller sample volume.
Use lavender top tube.
Contain EDTA to preserve blood cell morphology, inhibits clotting by binding Ca.
Good for hematology tests (eg. complete blood count).
Bad for: tests for divalent elements like Ca, Mg, or enzymes that require those ions as
cofactors (g. those used in clotting cascade)
Most (about 66%) of lab errors occur in the preanalytical phase. List
examples/opportunities for preanalytical error. - Answer-Incorrect sample type
Incorrect order of draw
Underfilled tubes
Tubes not mixed properly after collection
Sample hemolysis
Extreme temperature exposure/storage conditions (may affect analyte stability)
Delayed transportation
Time from collection to processing or analysis
Accuracy of lab tests (Define) - Answer-Ability of data, measurements or results to
match the "true" value
, Precision of lab tests (define) - Answer-How close the data, measurements or results
are to each other, working as a measure of the spread of data from the average
In terms of accuracy and precision, what are the best and worst lab tests? - Answer-
Best lab tests have high accuracy and high precision
Worst lab tests have low accuracy and low precision
What is the decision threshold line? - Answer-Lab tests are often used to confirm (rule
in) or exclude (rule out) a disease.
Decision threshold line is the cutoff value for deciding
Compare specificity vs sensitivity of lab tests. - Answer-Specific:
Considers Non-Diseased population and describes absence of disease.
A specific tests gives negative results in non-diseased subjects.
High true negative and low false positive.
Sensitive:
Considers Diseased population and describes presence of disease.
A sensitive test gives positive results in diseased subjects.
Low false negative and high true positive.
How do you measure specificity - Answer-TN / (TN+FP)
How do you measure sensitivity - Answer-TP / (TP+FN)
What is prevalence? - Answer-% of patients that have the disease that are being tested
What is a ROC curve? - Answer-Receiver Operating Characteristic curve
plots the false positive rate (1-specificity) against the true positive rate (sensitivity)
Several decision thresholds are selected, sensitivities and specificities are calculated
then plotted
How do you determine the better test from an ROC curve? - Answer-The curve with the
greater area below the curve is the better test.
What is laboratory stewardship? - Answer-The appropriate utilization of lab tests which
encompasses:
Correctly ordering tests
correctly retrieving tests
correctly interpreting tests
