Histology Certification Quality Control and Quality Assurance 1 — Questions and Answers
Question 1: What is the primary purpose of running a positive control slide in immunohistochemistry?
- To confirm the antibody and detection system are functioning correctly (Correct answer)
- To verify staining is negative in normal tissue
- To test the quality of the mounting medium
- To assess the pH of the buffer solution
Correct answer: To confirm the antibody and detection system are functioning correctly
A positive control contains known antigen and confirms the antibody and detection system are working properly before patient results are reported.
Question 2: Which organization provides the accreditation checklist most widely used for histology laboratory quality standards in the United States?
- American Medical Association (AMA)
- College of American Pathologists (CAP) (Correct answer)
- American Association of Clinical Chemistry (AACC)
- National Institutes of Health (NIH)
Correct answer: College of American Pathologists (CAP)
CAP accreditation is the gold standard for histology labs in the US, with specific checklists covering all aspects of laboratory QC and safety.
Question 3: A Levey-Jennings chart is used in histology QC primarily to:
- Record tissue fixation times for each case
- Track staining results over time to detect trends and shifts (Correct answer)
- Document reagent lot numbers and expiration dates
- Monitor autoclave temperature cycles
Correct answer: Track staining results over time to detect trends and shifts
Levey-Jennings charts plot QC data points over time, helping identify systematic trends, shifts, or random errors in staining performance.
Question 4: What does 'lot-to-lot verification' mean in histology quality control?
- Comparing staining results between different lab technicians
- Testing new reagent batches against established performance criteria before routine use (Correct answer)
- Verifying tissue sections from consecutive tissue blocks are equivalent
- Comparing staining results between morning and afternoon shifts
Correct answer: Testing new reagent batches against established performance criteria before routine use
Lot-to-lot verification ensures new reagent batches perform equivalently to previous batches before they are introduced into routine patient testing.
Question 5: When a routine H&E QC slide fails to meet acceptable standards, the first action a histotechnologist should take is to:
- Report the failure to the pathologist immediately and hold all cases
- Discard all patient slides stained in that run
- Investigate and identify the root cause of the failure (Correct answer)
- Repeat the stain using an entirely different protocol
Correct answer: Investigate and identify the root cause of the failure
Root cause analysis must be performed first to determine whether the issue is with reagents, equipment, or technique before any corrective action can be taken.
Question 6: Which document type formally describes the step-by-step instructions for performing a specific histology procedure to ensure consistency?
- Quality manual
- Standard operating procedure (SOP) (Correct answer)
- Laboratory logbook
- Proficiency testing report
Correct answer: Standard operating procedure (SOP)
An SOP is the official document detailing every step of a procedure, ensuring reproducibility and consistency among all laboratory staff.
Question 7: Proficiency testing (PT) in histology laboratories serves primarily to:
- Train new laboratory employees on staining techniques
- Compare a lab's performance against external standards and peer laboratories (Correct answer)
- Verify the accuracy of individual microscopes used for diagnosis
- Document reagent inventory and expiration tracking
Correct answer: Compare a lab's performance against external standards and peer laboratories
Proficiency testing evaluates a laboratory's competency by having staff process and interpret externally distributed samples, comparing results to peer labs and reference standards.
Histology Certification Quality Control and Quality Assurance 1
What is the primary purpose of running a positive control slide in immunohistochemistry?