MLPAO Specimen Processing and Handling Questions and Answers 2

Question 1

What is the maximum acceptable cold ischemia time for a kidney transplant organ from declaration of brain death to organ reperfusion?

Accepted Answer

12-36 hours

Answer

2-4 hours

Answer

6-12 hours

Answer

48-72 hours

Question 2

A CSF specimen is collected in three tubes. Which tube should be sent to the microbiology laboratory for culture?

Accepted Answer

Tube 2 — least likely to be contaminated with skin flora

Answer

Tube 1 — most likely to contain pathogens

Answer

Tube 3 — largest volume

Answer

Any tube may be used for culture

Question 3

A laboratory receives a serum specimen for cortisol measurement labeled 'AM cortisol — 0900 hours.' The specimen was collected at 0900 but not processed until 1600. Is this specimen acceptable?

Accepted Answer

No, cortisol may degrade; check stability guidelines and consider recollection if outside stability limits

Answer

Yes, cortisol is stable in serum at room temperature for 24 hours

Answer

Yes, if the specimen has not been centrifuged yet

Answer

No, cortisol must always be processed within 30 minutes of collection

Question 4

What does 'aliquoting' a specimen mean in laboratory specimen processing?

Accepted Answer

Dividing a primary specimen into smaller portions for multiple tests or storage

Answer

Discarding excess specimen after analysis

Answer

Mixing a specimen by inversion before analysis

Answer

Filtering a specimen to remove particulates

Question 5

Which of the following correctly describes the impact of lipemia on clinical chemistry test results?

Accepted Answer

Lipemia causes interference in multiple assays by light scattering, false volume exclusion, and reagent interference

Answer

Lipemia only affects triglyceride measurements

Answer

Lipemia has no significant effect if specimens are centrifuged before analysis

Answer

Lipemia only affects colorimetric assays and not immunochemical assays

Question 6

When storing serum specimens for up to 7 days pending batch analysis, what is the appropriate storage temperature?

Accepted Answer

Refrigerator (2-8°C)

Answer

Room temperature (15-25°C)

Answer

Freezer (-20°C)

Answer

Ultra-low freezer (-70°C) for all analytes