新型冠状病毒奥密克戎株核酸检测循环阈值与感染患者转阴周期的相关性及影响因素分析

Correlation and influencing factors analysis of the cycle threshold value in detection of novel coronavirus nucleic acid(Omicron)and the negative conversion cycle in infected patients

目的:探讨入院首次新型冠状病毒(新冠)奥秘克戎株(Omicron)核酸检测ORF1ab基因、N基因的循环阈值(cycle threshold,Ct)与新冠感染患者转阴周期之间的相关性及其影响因素。方法:选取2022年3月到4月期间,上海交通大学医学院附属瑞金医院北部院区收治的5212例新冠奥密克戎变异株感染者,依据患者既往史及入院后相关指标检验,将其分为无基础疾病组(2746例)及合并基础疾病组(2466例)。检测所有研究对象ORF1ab基因和N基因的Ct值,分析入院首次检测不同Ct值下无基础疾病组与合并基础疾病组的ORF1ab基因、N基因的转阴周期之间的差异。采用Pearson线性相关性分析,评估ORF1ab基因、N基因检测的Ct值与转阴周期的相关性,并采用多元线性回归分析转阴周期的影响因素。结果:新冠患者ORF1ab基因、N基因的Ct值与转阴周期均呈负相关(rORF1ab=-0.4622,P<0.01;r_(N)=-0.5428,P<0.01)。Ct值≤20和20<Ct值≤30的情况下,合并基础疾病组的转阴周期均明显长于无基础疾病组,差异有统计学意义(P<0.05)。多元线性回归分析显示,ORF1ab基因的Ct值每升高一个循环次数,转阴周期缩短0.21 d,N基因的Ct值每升高一个循环次数,转阴周期缩短0.26 d;年龄合并基础疾病为危险因素。结论:入院首次检测的新冠奥密克戎株ORF1ab基因、N基因的Ct值与新冠患者转阴周期有关,年龄、基础疾病为转阴周期长的危险因子,该值可作为新冠患者转阴周期的预测因子,可今后指导新冠患者减少核酸检测频次及评估疾病进程具有一定价值。

Objective:To explore the relationship between the cycle threshold(Ct)value of ORF1ab gene and N gene in the first admission detected by novel coronavirus(Omicron)nucleic acid and the negative conversion cycle of infected patients.Methods:5212 patients with novel coronavirus omicron variant infection were admitted to the Northern Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from March 2022 to April 2022 were collected,according to the patient′s previous history and the tests of relevant indexes after admission,including 2746 cases in non-basic disease group and 2466 cases in the basic disease group.All subjects received the Ct value of the ORF1ab genes and the N genes tests.Statistical analysis of the difference of the negative conversion cycle of ORF1ab gene and N gene between non-basic disease group and basic disease group under different Ct values at the first admission.Pearson linear correlation analysis was used to assess the association of Ct value of ORF1ab gene and N gene with the negative conversion cycle,and multiple linear regression was used to analyze the factors affecting the negative conversion cycle.Results:The Ct values of ORF1ab gene and N gene in patients novel coronavirus infection were negatively correlated with the negative conversion cycle(rORF1ab=-0.4622,P<0.01;r_(N)=-0.5428,P<0.01).In the case of Ct value≤20 and 20<Ct value≤30,there was a significant difference in the negative conversion cycle between the group with basic diseases and the group with non-basic disease,which the negative conversion cycle of the group with basic diseases was significantly higher than that of the group with non-basic disease(P<0.05);When the Ct value of the ORF1ab gene increases by one cycle,the negative conversion cycle is shortened by 0.21 days,and when the Ct value of the N gene increases by one cycle,the negative conversion cycle is shortened by 0.26 days,in addition,age and basic diseases are risk factors.Conclusions:The Ct values of ORF1ab gene and N gene in the first admission are related to the negative conversion cycle of patients with novel coronavirus(Omicron)infection,which can be used as an independent predictor of the negative conversion cycle of patients with novel coronavirus infection and have a certain value in guiding patients with novel coronavirus infection to reduce the frequency of nucleic acid detection and to assess disease progression.