Reference Ranges for ot-Amylase in Serum and Urine with 4?6-Ethylidene-(G7)-l-4-nitrophenyl-(Gl)-a5D-maltoheptaoside äs Substrate

Reference ranges for -amylase in serum, spontaneously voided urine, and 24h urine were determined, using 4,6-ethylidene-(G7)-l-4-nitrophenyl-(Gl)-a,£)-malthoheptaoside äs the Substrate (EPS method), at 25, 30, and 37 °C. The measured values were evaluated with and without the use of a factor which converts the results of the -amylase EPS method into values comparable to those obtained with the -amylase PNP method (substrate: 4-nitrophenyl-a,£>-matoheptaoside); comparison with the established reference ranges of the PNP method was therefore possible. Ttie values for urine sometimes deviated markedly ffom the PNP reference ranges, but the values for serum showed close agreement. With the use of the conversion factor, the following reference ranges are proposed for the new -amylase method: Serum (186 males and 131 females): up to 120 U/l (25 °C), up to 160 U/l (30 °C), and up to 220 U/l (37 °C). Spontaneously voided urine: up to 600 U/l (n = 323, 25 °C), up to 800 U/l (n = 373, 30 °C), and up to 1000 U/l (n = 373, 37 °C). 24 h urine: up to 450 U/24 h (n = -90, 25 °C), up to 650 U/24 h (n = 129, 30 °C), and up to 900 U/24 h (n = 129, 37 °C).