干血滤纸片法测定血清肌酸激酶实验研究

目的 建立干血滤纸片肌酸磷酸激酶检测方法,分析干血滤纸片法与静脉血清法所测得结果的相关性,界定微最法肌酸磷酸激酶病理性高值的"阈值".方法 收集100份标本,分别应用静脉血清法和干血滤纸片法检测肌酸磷酸激酶活性,运用统计学方法对两种方法检测的结果进行相关性分析.利用受试者工作特征曲线界定干血滤纸片法肌酸磷酸激酶病理性高值的"阈值".结果 将肌酸磷酸激酶>170 IU/L作为分界线,经静脉血清法检测,100份标本中50份为异常高值,50份为正常.经统计学分析,静脉血清法和干血滤纸片法所测定肌酸磷酸激酶结果存在正相关,但两种方法测得的肌酸磷酸激酶值不可直接比较和互换.当病理性肌酸磷酸激酶高值的"阈值"定为150.5 IU/L时,干血滤纸片法敏感度和特异度均为90%;当病理性肌酸磷酸激酶高值的"阈值"定在400 IU/L时,干血滤纸片法检测肌酸磷酸激酶灵敏度为70%,特异度为72%.结论 干血滤纸片法和静脉血清法所测结果存在良好相关性.兼顾实验敏感度和特异度,用于肌酸磷酸激酶筛查时的"阈值"建议定为400 IU/L.

Study of creatine phosphokinase with dried blood spot determination

Objective To establish dried blood spot determination for quantitative analysis of creatine phosphokinase (CK) activity; To analyze the correlation of CK value between serum detection and dried spot determination, and set up a 'cut-off point' for screening of pathologically high CK values in dried blood spot determination. Methods A total of 100 samples were analyzed quantitatively with two methods (serum detection and dried blood spot determination) for CK activity. The correlation of the two methods was studied. The ' cut-off point' for screening of pathologically high CK in dried blood spot determination was calculated with receiver operating characteristic curve (ROC curve). Results Of the 100 samples, 50 were normal and other 50 were abnormal when the 'cut-off point' was set at serum CK of 170 IU/L. There was a positive correlation in CK values between serum detection and dried blood spot determination (r = 0.764, P < 0.01). However, the values measured with the two methods could not be interchanged. The sensitivity and the specificity were 90% when the 'cut-off point' was set at 150 lUlL. The sensitivity and the specificity were 70% and 72%, respectively, when the 'cut-off point' was set at 400 IU/L. Conclusions There was a good correlation in CK activity between serum detection and dried blood spot determination. 400 IU/L could be suggested as the 'cut-off point' for detecting pathologically high CK in dried blood spot determination.