NHA Certified Phlebotomy Technician (CPT)Collection RoutineHard
A phlebotomy technician is preparing to collect a blood specimen for a cold agglutinin test. Which of the following special handling procedures is required for this specimen?
- ACentrifuge the specimen within 30 minutes of collection.
- BProtect the specimen from light during transport.
- CKeep the specimen warm at 37°C (98.6°F) after collection.
- DPlace the specimen on ice immediately after collection.
Show answer & explanationAnswer & explanation
Correct answer: C. Keep the specimen warm at 37°C (98.6°F) after collection.
Cold agglutinins are antibodies that react at cold temperatures. To prevent them from clumping (agglutinating) and affecting test results, the specimen must be kept warm at body temperature (37°C) from the moment of collection until it is processed in the lab.
Why the other options are wrong
- A. Centrifugation is a processing step, but premature or improper centrifugation without maintaining warmth can still affect cold agglutinin results.
- B. Protecting from light is necessary for light-sensitive analytes like bilirubin, but not for cold agglutinins.
- D. Placing on ice is required for some tests (e.g., ammonia, lactic acid) but would cause cold agglutinins to react and clump.
Cold Agglutinin Specimen Handling
Specific handling required for specimens collected for cold agglutinin tests, where the blood must be kept warm at body temperature (37°C) from collection to processing to prevent the agglutinins from reacting.
- Cold agglutinins are antibodies that clump red blood cells at cold temperatures.
- Specimen must be collected in a pre-warmed tube.
- Transport immediately to the lab while maintaining warmth (e.g., in a heel warmer or warm block).
- Prevents false positive or inaccurate results due to agglutination.
Memory trick: TEMP MATTERS: Temperature, Exposure, Moisture, Protection, Agitation, Timing.