Newborn screening dried blood spot analysis by tandem mass spectrometry (MS/MS) requires pre-processing the specimen with one of two alternative reagent methods referred to as derivatized and non-derivatized (or underivatized) methods. The methods are similar and nearly all analytes and ratios are identical with the limited number of exceptions noted in the description of the LOINC codes. Some labs choose to use the non-derivatized method because it may be faster or less expensive for their operations. There are no analytes which would be interpreted differently based on the method used to process the specimen so there is no need for different LOINC codes for the same compounds based on the reagents. In a few cases, a different LOINC code is used for the derivatized or non-derivatized tandem mass spectrometry (MS/MS) method because based on the reagents used in processing, different analytes are measured or different sets of analytes become isobaric, which means that they cannot be distinguished on the MS/MS because they have the same molecular weight after reagent processing.
status
ACTIVE
Fully-Specified Name
component
Acylcarnitine newborn screen panel
property
-
time
Pt = Point in time: To identify measures at a point in time. This is a synonym for “spot” or “random” as applied to urine measurements.
LOINC codes that represent optional associated observation(s) for a clinical observation or laboratory test. A LOINC term may represent a single associated observation or panel containing several associated observations.