儿童甲型流感病毒暴发性心肌炎2例临床分析并文献复习

Clinical analysis of two children with fulminant myocarditis following an influenza A infection and literature review

目的探讨甲型流感病毒导致暴发性心肌炎的临床特征。方法回顾分析2例由甲型流感病毒感染导致暴发性心肌炎患儿的临床资料。结果2例患儿均急性起病。例1为女性,14岁,高热2天后出现乏力、腹痛、肌肉疼痛,病情加剧出现呼吸困难、意识丧失,随后出现心源性休克;咽拭子甲型H3N2流感病毒核酸检测阳性,肌钙蛋白T(cTnT)29.5 ng/mL,肌酸激酶同工酶(CK-MB)20.3 ng/mL,B型钠尿肽前体(Pro-BNP)>35000 pg/mL;心脏彩超示左心室明显增大,射血分数(EF)30%;因疾病进展迅速死亡。例2为男性,2岁10月龄,发病前5天有高热及呼吸道前驱感染症状,伴乏力、腹胀、腹痛、胸闷及呼吸困难;咽拭子甲型H1N1流感病毒核酸检测阳性,cTnT 0.35 ng/mL,CK-MB 10.43 ng/mL,Pro-BNP 9740 pg/mL;心脏彩超示全心腔增大,EF 48%;心电图为窦性心律,Ⅲ度房室传导阻滞;经积极治疗好转出院。1个月后出现胸闷、乏力、双下肢水肿、活动量减少等心功能不全表现;动态心电图示平均心率55次/min,最慢心率45次/min,全程可见Ⅲ度房室传导阻滞;心脏彩超示心脏各房室内径增大;予安装永久起搏器,1周后水肿消退,复查心腔大小正常,心功能无异常。随访6个月心脏大小及心功能无异常,胸闷、乏力未再复发。结论儿童甲型流感病毒感染可导致暴发性心肌炎,临床症状及体征不典型,进展迅速,可导致严重并发症甚至猝死,须早期诊断和治疗。

Objective To investigate the clinical features of fulminant myocarditis following an influenza A infection,to reduce misdiagnosis,and to improve early treatment and prognosis.Methods The clinical data of two children with fulminant myocarditis caused by influenza A were retrospectively analyzed.Results Both of the two cases were presented with acute onset.Patient 1 was a 14-year-old female who had seasonal flu symptoms with heart failure following myocarditis but was otherwise healthy.H3N2 influenza virus infection was detected by molecular analyses of throat and nasal swabs,serum cTnT was 29.5 ng/mL,CK-MB 20.3 ng/mL and Pro-BNP>35000 pg/mL,with left ventricular dysfunction and ejection fractions 30%.Patient 2 was a 2 years and 10 months old male with the third degree atrioventricular block following myocarditis who had seasonal flu symptoms.H1N1 influenza virus infection was detected by molecular analyses of throat and nasal swabs,with left ventricular dysfunction and ejection fractions of 48%,cTnT 0.35 ng/ml,CK-MB 0.43 ng/ml,Pro-BNP 9740 pg/mL.He was given large doses of steroids and immunoglobulin therapy at the same time,and myocardial nutrition,anti-viral,correcting heart failure,and other comprehensive treatments were also given.He was discharged from hospital in good condition.One month later he developed clinical manifestations of cardiac insufficiency,and the whole 24 hours Holter showed the third degree atrioventricular block,then he was treated with permanent pacemaker implantation.After following-up for 6 months,he was in good condition.Conclusions Influenza A virus infection can cause myocarditis,which comprises a wide spectrum of cardiac involvement from mild myocarditis to cardiogenic shock.Fulminant myocarditis may occur during influenza A virus infection in young individuals,even those with no known predisposing factors.Physicians need to be aware that fulminant myocarditis can be a fatal complication of influenza virus infection in all patients with instable hemodynamics.Early diagnosis and treatment could reduce,in some cases,the risk of severe cardiac events.