We report on the clinical usefulness of alkaline phosphatase isoenzyme determinations using a combined chemical inhibition method on 731 patient serum specimens exhibiting elevated (greater than 350 U/L) alkaline phosphatase (AP) activity. 2. The relative percentages of the organ-specific alkaline phosphatase activities were computed on the basis of three independent assays: total activity, activity in the presence of 10 mMl-phenylalanine, and activity in the presence of 3.1 M urea. 3. Gamma-glutamyl transferase (GGT) activity assays were also performed on the same specimens. Using an upper reference limit of 30 U/L for GGT and comparing the GGT results with the percent liver AP, we found that the GGT results were 91% sensitive and 60% specific. 4. We conclude that AP isoenzyme determinations are very useful in identifying the organ source(s) responsible for elevated AP values. 5. The reference ranges for several age groups in relation to the adult population and their significance are presented.
摘要
我们报告了采用联合化学抑制法测定731份碱性磷酸酶（AP）活性升高（大于350 U/L）的患者血清标本中碱性磷酸酶同工酶的临床实用性。2. 根据三项独立检测计算器官特异性碱性磷酸酶活性的相对百分比：总活性、在10 mM L-苯丙氨酸存在下的活性以及在3.1 M尿素存在下的活性。3. 对相同标本也进行了γ-谷氨酰转移酶（GGT）活性检测。使用GGT的上限参考值30 U/L，并将GGT结果与肝脏AP百分比进行比较，我们发现GGT结果的敏感性为91%，特异性为60%。4. 我们得出结论，AP同工酶测定对于确定导致AP值升高的器官来源非常有用。5. 给出了与成人人群相关的几个年龄组的参考范围及其意义。
