尿酸酶-过氧化物酶偶联反应检测血清尿酸过程中的干扰分析

Analysis of interference factors in measurement of serum uric acid by uricase-peroxidase coupled reaction

目的:探讨采用尿酸酶-过氧化物酶偶联反应测定血清尿酸(uric acid,UA)过程中的干扰因素及排除方法。方法:结合临床工作中2个尿酸酶-过氧化物酶偶联反应检测UA水平异常低值病例,观察反应曲线,探究导致血清UA假性异常降低的原因,并尝试消除干扰。结果:病例1的血清UA初次检测结果为18.2μmol/L,根据反应曲线推测,是由于该患者使用的外源性药物拉布立酶降解了UA,从而造成检测结果UA水平降低,故重新采样时将血液采集至预先冷藏的肝素抗凝管中,去除干扰后,获得的UA检测结果为102.0μmol/L。病例2的血清UA检测结果为负值,观察反应曲线和体外实验发现蛋白沉淀,推测M蛋白为内源性干扰物,采用PEG6000蛋白沉淀法予以纠正后,获得血清UA检测结果为158.5μmol/L。结论:多种外源性和内源性因素均可影响尿酸酶-过氧化物酶偶联反应检测获得的血清UA结果,出现异常值时应结合反应曲线加以区分、纠正,为临床提供更为精准的检测结果。

Objective To explore the possible interference factors in the measurement of serum uric acid(UA)by uricase-peroxidase coupled reaction and the methods to eliminate these interference factors.Methods:Two cases with pseudo-hypouricemia detected by uricase-peroxidase coupled reaction were analyzed.Causes for interference on measurement were analyzed via alarm message and reaction curve displayed on the instrument.Different approaches were adopted to eliminate the interference on measurement of serum UA.Results:The initial measurement value of serum UA for case 1 was 18.2μmol/L.According to the reaction curve,it was speculated that the low UA value might be caused by the administration of Rasburicase.Thereafter,the blood sample withdrawn from case 1 was recollected into pre-cooled heparin tube,and the corrected value was 102.0μmol/L.The initial measurement value of serum UA of case 2 was a negative value,the reaction curve and appearance of protein precipitation in in-vitro test indicated that the internal M protein was suspected to lead to the false decrease of serum UA value.The UA value of case 2 was normalized to 158.5μmol/L via the PEG6000 protein precipitation method.Conclusions:Measurement of serum UA by uricase-peroxidase coupled reaction may be affected by various exogenous and endogenous factors.When the UA value comes to be abnormal,comprehensive analysis of reaction curve is needed to confirm the interference factor,which helps to achieve more accurate test results in clinical setting.