2022年11月10日

致编辑:我们此前曾报道，在以色列，在接种了抗2019冠状病毒病(Covid-19)的BNT162b2信使RNA疫苗(辉瑞- biontech)后，16至29岁男性的心肌炎发病率最高(每10万人中有10.7例)。此后，BNT162b2疫苗已被批准用于12至15岁的青少年，以色列这一年龄组的初步证据表明，心肌炎的发病率相似，病程较轻，但随访仅限于30天。2来自香港的一项研究显示，发病率为每10万人28.7例，但这些病例的判决没有超出《国际疾病分类第九修订版》(ICD-9)的出院诊断代码。我们的目的是提供关于青少年接种疫苗后心肌炎发生率的进一步证据和随访6个月或更长时间的数据。我们收集了从2021年6月2日至11月30日在Clalit Health Services(以色列最大的卫生保健组织)数据库中列出的患者的信息。我们使用ICD-9代码来识别心肌炎病例，并使用每个患者电子医疗记录中的所有可用数据进行判定。如前所述，住院和随访数据收集到2022年2月26日。详细的方法和定义在补充附录中提供，可在NEJM.org上获得本信函的全文。图1所示。图1所示。 Cumulative Incidence of Myocarditis after BNT162b2 Vaccination among Israeli Adolescents 12 to 15 Years of Age. Shown is the cumulative incidence of myocarditis during a 42-day period after the receipt of the first dose of the BNT162b2 vaccine in Israel among 182,605 vaccinated adolescents between the ages of 12 and 15 years of age who were enrolled in the Clalit Health Services. A diagnosis of myocarditis was made in 9 patients. The vertical dashed line at 21 days indicates the median day of administration of the second vaccine dose. The shaded area represents the 95% confidence interval. Of 182,605 adolescents who had been vaccinated during this period, 20 potential cases of myocarditis were identified. A total of 9 cases were adjudicated as probable or definite myocarditis, according to the case definition of the Centers for Disease Control and Prevention. This finding translated to an incidence of 4.8 cases (95% confidence interval, 1.7 to 7.9) per 100,000 persons ( Figure 1 ); 8 cases occurred after the second vaccine dose (Fig. S1 and Table S1 in the Supplementary Appendix ). Incidence values that are stratified according to sex and age are provided in Table S2. All cases of myocarditis were classified as mild, 4 and the condition of patients was hemodynamically stable at presentation. Abnormal electrocardiographic (ECG) results were reported in 67% of the patients, and cardiac and inflammatory markers were elevated in all the patients. The in-hospital course of the patients was uneventful, and the median duration of admission was 3 days (interquartile range, 2 to 4 days) (Table S3). Eight patients had a normal ejection fraction, and four had a pericardial effusion (Table S4). Echocardiographic findings were available for 8 of 9 patients after hospital discharge (median interval, 10 days). All echocardiograms showed a normal ejection fraction and resolution of pericardial effusion (in cases in which the latter had previously been identified). Five patients underwent cardiac magnetic resonance imaging (including three scans that were performed at a median of 104 days after discharge) with minimal evidence of myocardial scarring or fibrosis, with evidence of late gadolinium enhancement ranging from 0 to 2%. At a median follow-up of 206 days (interquartile range, 192 to 229 days) after hospital discharge, all the patients were alive and none had been readmitted to the hospital. Our study indicates that BNT162b2 vaccine–induced myocarditis in adolescents appears to be a rare adverse event that occurs predominantly in males after the second vaccine dose. The clinical course appears to be mild and benign over a follow-up period of 6 months, and cardiac imaging findings suggest a favorable long-term prognosis. Guy Witberg, M.D., M.P.H.