新型冠状病毒肺炎患者抗核抗体谱分析和血清加热灭活对检测的影响

ANA profiles in COVID-19 patients and influence of serum heat-inactivation on ANA determination

目的探讨新型冠状病毒肺炎(COVID-19)患者抗核抗体(ANA)谱特征和血清热灭活对ANA检测结果的影响。方法选取2022年3—5月复旦大学附属华山医院宝山院区疑诊自身免疫性疾病(AID)的患者49例,分析其血清ANA阳性特征。同时,以56℃、30 min金属浴灭活血清作为观察组,比较其与对照组(未处理血清)使用间接免疫荧光法和线性免疫印迹法检测ANA结果之间的差异。结果COVID-19患者ANA阳性率为48.98%,荧光模型多样,包括AC-4型(细颗粒型)6例、AC-1型(均质型)5例、AC-3型(着丝点型)2例、AC-10型(核仁颗粒型)1例、AC-20型(胞质细颗粒型)3例和混合核型7例;其中中、低滴度(≤1∶320)荧光核型22例(91.7%)、高滴度(≥1∶1000)2例(8.3%)。ANA阳性组新型冠状病毒(SARS-CoV-2)ORF1ab基因、N基因Ct值和核酸转阴时间(NCT)与ANA阴性组比较差异均无统计学意义(P>0.05)。当COVID-19患者合并AID时ANA阳性率最高(55.6%),但与合并非AID(48.4%)和无基础疾病(44.4%)患者比较,差异均无统计学意义(P>0.05)。对照组与观察组荧光模型、荧光强度、靶抗原检测抗体种类和膜条显色强度无差异;ANA阴性患者血清热灭活后检测结果仍为阴性。结论ANA阳性对COVID-19患者病程转归的影响意义有限。血清56℃、30 min热灭活对COVID-19患者ANA的检出和核型、滴度分布,以及靶抗原的检测结果均无影响。

Objective To investigate the characteristics of antinuclear antibody(ANA)profiles in patients with corona virus disease 2019(COVID-19)and the influence of serum heat-inactivation on ANA determination.Methods Totally,49 patients with autoimmune disease(AID)from Baoshan Branch of Huashan Hospital of Fudan University from March to May 2022 were enrolled among whom the characteristics of ANA positive results were analyzed.After heating sera with metal bath at 56℃ for 30 min(observation group),the differences in the results of ANA by indirect immunofluorescent assay and line immunoassay between observation group and control group(untreated sera)were compared.Results The ANA determination was positive in 48.98%of patients'sera,with 22(91.7%)being positive with a low titer(≤1∶320)and 2(8.3%)being positive with a middle titer(≥1∶1000).ANA patterns were diverse,including 6 cases of AC-4(fine speckled),5 cases of AC-1(homogeneous),2 cases of AC-3(centromere),1 case of AC-10(punctate nucleolar),3 cases of AC-20(cytoplasmic fine speckled)and 7 cases of mixed patterns.There was no statistical significance in ORF1ab gene,N gene Ct values and the nucleic acid conversion time between ANA positive and ANA negative groups(P>0.05).The positive rate of ANA was the highest in COVID-19 patients with AID(55.6%),which was not significantly different from that in patients with non-AID(48.4%)and without underlying diseases(44.4%)(P>0.05).There was no statistical significance in types and intensity of ANA patterns and specific antibodies between observation and control groups with positive ANA results,and the results of ANA negative ones stayed negative after serum heat inactivation.Conclusions Positive ANA shows limited impact on disease outcome.Serum heat inactivation at 56℃for 30 min will not change the results of ANA determination,patterns,titers,target antigen determination in patients with COVID-19.