I型登革病毒感染后不同病程病毒核酸及其IgM抗体的变化规律

Dynamics of viral RNA and IgM antibody in patients with dengue virus type 1 infection

目的探讨I型登革病毒感染后病毒核酸及其IgM抗体在患者体内的变化规律,为指导临床快速、准确地诊断登革热提供理论支持。方法回顾性分析2014年7-11月收集的I型登革病毒感染者临床资料和血清标本,应用实时荧光定量RT-PCR和ELISA法分别检测病毒核酸和IgM抗体,分析不同病程两者的变化规律。结果共检出222例阳性患者,其中病毒核酸阳性137例,IgM抗体阳性146例,两者同时阳性61例。病程急性期(发病1~5 d)病毒核酸阳性率为75%~100%,IgM抗体阳性率在发病第1~2天较低,但第3~5天快速升高至50%~70%;进入恢复期(发病6~10 d)病毒核酸阳性率即快速降低,8 d后仅20%左右,但IgM抗体阳性率显著升高达95%~100%。急性期和恢复期病毒核酸与IgM抗体检测结果构成比差异有统计学意义(χ~2=63.41,P<0.05)。结论 I型登革病毒感染者急性期病毒核酸阳性率在75%以上。恢复期IgM抗体阳性率在95%以上。根据病程合理选择检测方法,可提高登革热的诊断效率。

Objective To investigate the dynamics of viral RNA and IgM antibody in patients infected with dengue virus type 1（ DV1）,in order to provide theoretical basis of rapid and accurate diagnosis of dengue fever. Methods Clinical data and serum samples of DV1 infected patients from July to November2014 were collected and retrospectively analyzed in this study. The dynamics of viral RNA and IgM antibody during the course of disease were analyzed by quantitative real-time reverse transcriptase polymerase chain reaction（ RT-PCR） and enzyme-linked immunosorbent assay（ ELISA）. Results A total of 222 positive samples including 137 positive for viral RNA,146 positive for IgM,and 61 positive for both were detected.The positive ratio of viral RNA was about 75% ～ 100% in acute phase（ day 1 to 5）. While the positive ratio of IgM antibody was low on day 1 to 2,but it increased quickly to 50% ～ 70% on day 3 to 5. In convalescent phase（ day 6 to 10）,the positive ratio of viral RNA rapidly decreased and was only about 20% after day 8.Meanwhile,the positive ratio of IgM antibody increased to 95% ～ 100%. There was a statistically significant difference in the constituent ratio of viral RNA and IgM antibody,i. e.,DV1（ ＋） IgM（-）,DV1（ ＋） IgM（ ＋）,DV1（-） IgM（ ＋）,between the acute phase and convalescent phase（ χ^2= 63. 41,P〈0. 05）.Conclusion In patients infected with DV1,the positive ratio of viral RNA is above 75% in acute phase,while the positive ratio of IgM antibody is above 95% in convalescent phase. The efficiency of diagnosis couldbe improved by applying more reasonable and effective detection assays according to the course of disease.