探讨心肌酶及其比值与肌钙蛋白的测定对儿童病毒性心肌炎的诊断

目的初步了解本地区儿童心肌酶的正常范围,探讨其比值及肌钙蛋白I(cTnI)对儿童病毒性心肌炎(VMC)的诊断价值。方法采用日立7080全自动生化分析仪来测定肌酸激酶(CK)、肌酸激酶同工酶MB(CK-MB)、乳酸脱氢酶(LDH)、α羟丁酸(αHBDH)并计算出CK-MB/CK、αHBDH/LDH;CK采用酶耦联测定法,αHBDH采用连续监测法,LDH采用连续监测法(LDHL),CK-MB采用免疫抑制法;cTnI采用固相层析免疫分析法测定。结果本地区100例健康儿童心肌酶水平均高于健康成人(P<0.01),但不同组的CK-MB/CK<2%的占85%以上,αHBDH/LDH在0.6~0.8之间占87%以上。50名健康儿童运动后的心肌酶普遍高出儿童正常范围,但其比值并未升高。已确诊的66例儿童病毒性心肌炎患者的心肌酶异常的有55例(占84%),CK-MB/CK>6%的有41例,αHBDH/LDH>0.8的有39例,cTnI结果阳性的有46例,比值和cTnI的结果经配对检验,存在一致性关联。结论不能用成人的标准来判断儿童心肌酶异常与否,儿童心肌酶单项升高不能作为VMC的诊断依据;CK-MB/CK>6%、αHBDH/LDH>0.8以及cTnI结果阳性对诊断VMC有极大的临床价值。

Investigation on the diagnostic value of measurement of myocardial enzymes and their ratio and CTnl in children′s viral myocarditis

Objective To inquire the normal range of children myocardial enzymes in the local area,and study the diagnostic value of the ratio and cardiac troponin I(cTnI)in children's viral myocarditis(VMC).Methods Creatine kinase(CK),lactate dyhydrogenase(LDH),and α-hydrooxybutyrate dehydrogenase(αHBDH) were detected with cotinuous monitoring assay and creatine kinase isoenzyme MB(CK-MB) with immunity restrain assay with Hitachi 7 080 A complete automatic biochemistry analyzer,and CK-MB/CK,and αHBDH/LDH were calculated.cTnI was measured with solid phase immunochromatographic method.Results The level of myocardial enzymes was significantly higher in 100 cases of healthy children than that of healthy adults in the local area(P<0.01).The percentage of CK-MB/CK <2% subjects was over 85%,of αHBDH/LDH 0.6-0.8 ones was over 87%.The levels of myocardial enzymes exceed children's normal reference range after sports,but the ratios didn't go up.In 66 cases of definitely-diagnosed viral myocarditis,55 cases suffered from myocardial abnormality(84%).41 cases were with CK-MB/CK >6%,and 39 cases αHBDH/LDH >0.8.46 cases were cTnI positive.The ratio was associated with cTnI level via matched test.Conclusion Children's myocardial enzyme normality or not can't be judged by adult standards.The elevation of a single children's myocardial enzyme can't be regarded as diagnostic basis.CK-MB/CK >6%,αHBDH/LDH >0.8 and cTnI positive result contribute to the diagnosis of viral myocarditis.