微量荧光法在苯丙酮尿症诊治中的应用

目的 :探讨微量荧光法定量苯丙氨酸在苯丙酮尿症 (PKU)诊治中的应用。方法 :对芬兰 L absystem s公司生产的新生儿苯丙氨酸定量试剂盒及设备进行方法学鉴定 ,并测定 194 7例新生儿和 2 8例经典苯丙酮尿症患儿及 8例持续性高苯丙氨酸血症患儿末梢血中苯丙氨酸 (Phe)水平观察其实用性。结果 :经实验方法学鉴定 ,本法高、中、低各浓度批内平均变异系数 (CV)为0 .0 36 ,0 .0 6 9,0 .0 6 8,批间平均变异系数 (CV)为 0 .12 4 ;最低检测极限为 31μmol/ L ;平均重现率为 98.4 %。新生儿血苯丙氨酸水平正常参考范围 :31～ 12 0 μmol/ L。 2 8例经典苯丙酮尿症和 8例持续性高苯丙氨酸血症患儿血苯丙氨酸平均含量分别为 186 7μmol/ L(s=4 0 9.8)和 76 9μmol/ L(s=2 2 6 .2 ) ,三者间有显著性差异 P<0 .0 0 1。患儿治疗前后苯丙氨酸平均含量有明显差异 P<0 .0 0 1。结论 :微量荧光法定量准确操作简便适于 PKU诊治观察

Application of Tracer Fluorimetry in Diagnosis and Treatment of Phenylketonurea

This study discusses the application of tracer fluorimetry in the diagnosis and treatment of phenylketonurea(PKU)by detecting phenylalanine (Phe) content in the blood of newborns. A methodological evaluation was made to test Labsystems Kit and Apparatus for quantitative analysis of Phe content, and the Phe level of peripheral blood was determined in 1947 newborns (>3 days old), 28 typical PKU children and 8 children with prolonged hyperphenylalaninemia. According to the experimental evaluation, the average in batch coefficient of variation (CV) in high, medium and low concentrations was 0.036, 0.069, 0.068 respectively; the mutually compared average CV in high, medium and low concentrations was 0.124; the minimum limit of the fluorimetry was 31 μmol/L; and the mean recurrence rate was 98.4 %. Normally, the reference values of Phe content in the blood of newborns range from 31 to 120 μmol/L, but the average Phe content in the 28 typical PKU children and 8 children with prolonged hyperphenylalaninemia was 1 867 μmol/L(s=409.8) and 769 μmol/L(s=226.2)respectively, showing a statistically significant difference(P<0.001)between the normal group, PKU group, and hyperphenylalaninemia group. The difference of the Phe content of the children among before and after treatment was very significantly statistically(P<0.001). In conclusion, tracer fluorimetry is accurate and convenient, so it is recommendable to be used for screening PKU.