9. A phlebotomist should identify that a blood spot collection for inborn errors of metabolism requires which of the following?
Answer: D
The specimen must be completely dried before the test can be processed.
For blood spot collections used in screening for inborn errors of metabolism, it is crucial that the specimen is completely dried before processing. This ensures the integrity of the sample and accurate test results.
A) The newborn must be at least 3 days old.
While it is often recommended that newborn screening tests are performed after a certain age, this option does not address the specific requirements for blood spot collection. The age of the newborn is pertinent but does not directly pertain to the drying process of the specimen.
B) The circles on the filter paper must be at least half filled.
This statement relates to the adequacy of the blood sample on the filter paper but does not encompass the essential step of ensuring the specimen is dried before testing. Therefore, while it may be important for collection, it does not meet the critical requirement emphasized in the question.
C) The first drop of blood immediately following the puncture must be included.
Including the first drop of blood is not a requirement for blood spot collection for metabolic screening. In fact, initial drops can be contaminated with tissue fluid and should typically be wiped away, making this option incorrect in the context of proper collection practices.
D) The specimen must be completely dried before the test can be processed.
This option is essential and correct since complete drying of the blood spot is necessary to prevent degradation of the sample and ensure reliable test results. Proper drying allows the sample to be stable for transport and testing.
Conclusion
The correct answer emphasizes the vital requirement that the specimen must be completely dried before processing to ensure accurate test outcomes. The other options, while relevant to various aspects of sample collection, do not fulfill the critical condition necessary for successful blood spot testing in the context of inborn errors of metabolism. Thus, they are not as integral as the drying requirement highlighted in option D.