Comparison of pyridoxal phosphate-supplemented reagent kits for alanine aminotransferase using centrifugal analysis

The addition of pyridoxal-5-phosphate for assay of alanine aminotransferase has been recommended. The referral methods are inconvenient for high volume instrumentation due to use of multiple reagents and blanks. We adapted a well-documented method to the centrifugal analyzer as a reference for adaptation of two kit methods. Reference intervals obtained and linearity determined were all similar. The kit methods compared favorably to the referral method. Linear regression analysis yielded the following: DOW = 1.011 BERG + 1.666, r = 0.9965; SKI = 0.938 BERG + 4.559, r = 0.9926; and DSKI = 1.028 BERG + 1.051, r = 0.9889. Precision of the assays was acceptable. We concluded that automation of reagent kits incorporating pyridoxal-5-phosphate is feasible and the assays compared favorably to a recommended method. High volume instrumentation can be used without denigration of analytical quality and to allow comparability to a documented method for interlaboratory review.