Bean et al. (A-22) conducted a study to assess the performance of the isoelectric focusing/

immunoblotting/laser densitometry (IEF/IB/LD) procedure to evaluate carbohydrate-deficient transferrin (CDT) derived from dry blood spots. The investigators evaluated paired serum (S)

and dry blood spot (DBS) specimens simultaneously for CDT. Assessment of CDT serves as a marker for alcohol abuse. The use of dry blood spots as a source of CDT for analysis by IEF/ IB/LD results in simplified sampling, storage, and transportation of specimens. The following are the IEF/IB/LD values in densitometry units (DU) of CDT from 25 serum and dry blood spot specimens:

Specimen No. S DBS Specimen No. S DBS 1 64 23 14 9 13 2 74 38 15 10 8 3 75 37 16 17 7 4 103 53 17 38 14 5 10 9 18 9 9 6 22 18 19 15 9 7 33 20 20 70 31 8 10 5 21 61 26 9 31 14 22 42 14 10 30 15 23 20 10 11 28 12 24 58 26 12 16 9 25 31 12 13 13 7