Reference values of serum and urine α-amylase catalytic concentration using SEQC recommended procedure

Reference intervals for the catalytic concentration of total and pancreatic α-amylase in serum and spontaneously voided urine were determined in 318 blood donors and 234 urine donors. The method used 2-chloro-4- nitrophenyl-α-D-maltotrioside as substrate, which allows a continuous colorimetric measurement of the catalytic concentration of α-amylase without need of ancillary enzymes. The following reference ranges at 37 °C are proposed: Srm-α-Amylase 0.3-0.95 μkat/L, Srm-Pancreatic α-amylase 0.13- 0.45 μkat/L, Uri-α-Amylase 0.7-5.35 μkat/L, and Uri-Pancreatic α-amylase 0.37-3.35 μkat/L. No age and sex-related differences were found. Reference ranges were also determined using 4,6-ethylidene-1,4-nitrophenyl -α-D- maltoheptaoside (EPS method) as substrate. Obtained values were comparable with those established by the manufacturer.