From the Guidelines
If a blood sample for a comet test is contaminated with EDTA, it is recommended to discard the sample and collect a new one using the correct collection tube, as EDTA is not suitable for this test and can affect the results. The comet test, also known as the comet assay, is a sensitive method for detecting DNA damage, and the use of EDTA can interfere with the test's accuracy. According to the european recommendations and quality assurance for cytogenomic analysis of haematological neoplasms 1, the sample collection for cytogenomic analysis should be done using heparin for cell culture and EDTA for DNA-based analysis, but it is crucial to use the correct anti-coagulant for the specific test ordered. In this case, since the sample is contaminated with EDTA, which is not suitable for the comet test, it is essential to collect a new sample using the correct collection tube to ensure accurate results.
When collecting the new sample, it is crucial to ensure proper tube selection, adequate filling of the tube, gentle mixing after collection, and timely processing to prevent any further contamination or interference with the test results. The laboratory staff should be notified about the contamination issue to prevent recurrence and ensure accurate patient results.
It is also important to note that the use of EDTA can cause hemolysis, which can further affect the test results, and therefore, it is essential to handle the sample carefully and follow the recommended guidelines for sample collection and processing.
In summary, to ensure accurate results for the comet test, it is recommended to discard the contaminated sample and collect a new one using the correct collection tube, following the recommended guidelines for sample collection and processing 1.
From the Research
Issue with cmet Test Sample
- The cmet (comet) test sample is contaminated with EDTA, which is not suitable for the test ordered.
- EDTA is commonly used as an anticoagulant for hematological testing, but it can interfere with certain tests, including coagulation tests 2.
Effects of EDTA on Blood Samples
- EDTA can affect the results of coagulation tests, such as prothrombin time (PT) and partial thromboplastin time (PTT) 2.
- EDTA can also affect the morphology and function of blood cells, including platelets 3.
- The use of EDTA as an anticoagulant can lead to changes in the proteome content of platelets, which can influence the results of certain tests 3.
Recommendations for cmet Test Sample
- The sample should be recollected using a suitable anticoagulant, such as sodium citrate, which is commonly used for coagulation tests 4.
- The use of EDTA as an anticoagulant should be avoided for cmet tests, as it can interfere with the results 2.
- It is essential to follow the recommended guidelines for blood sample collection and processing to ensure accurate and reliable test results 4, 5.