Question 68

The specimen must be completely dried before the test can be processed.

For blood spot collection in inborn errors of metabolism, it is crucial that the specimen is completely dried to ensure accurate test results and prevent contamination.

A) The newborn must be at least 3 days old

This option is incorrect because while some testing guidelines suggest that newborns should be a certain age to ensure accurate results, the specific requirement for blood spot collection does not focus on the newborn's age. Instead, it emphasizes the drying process of the specimen.

B) The circles on the filter paper must be at least half filled

This option is also incorrect. The requirement for filling the circles on the filter paper pertains to the quality of the sample but does not address the critical step of ensuring the specimen is fully dried prior to testing, which is vital for reliable results.

C) The first drop of blood immediately following the puncture must be included

This choice is incorrect as it is generally recommended to discard the first drop of blood to avoid contamination from tissue fluid. The emphasis in blood spot collection is not on including the first drop but rather on the proper handling and processing of the sample.

D) The specimen must be completely dried before the test can be processed

This option is correct because allowing the blood spot to dry completely is essential for accurate testing. Moisture can affect the stability of the sample and lead to erroneous results, making this step critical in the collection process.

Conclusion

The requirement that the specimen must be completely dried before processing is fundamental to ensuring test accuracy in blood spot collection for inborn errors of metabolism. All other options, while they may touch on important aspects of the collection process, do not address the necessity of drying the specimen, which is a crucial factor in obtaining reliable test outcomes.