武汉地区人类博卡病毒呼吸道感染患儿的临床特点

目的研究武汉地区住院患儿呼吸道感染人类博卡病毒(Human Bocavirus,HBoV)的临床特点。方法选择2017年1-12月武汉市第三医院因呼吸道感染住院患儿1 438例以及健康儿童310名为研究对象。应用RT-PCR检测1 438例患儿咽拭子病毒感染情况;比较健康儿童和HBoV阳性患儿炎症指标水平;分析HBoV阳性患儿临床症状;采集HBoV阳性患儿咽拭子,进行扩增后基因测序,分析基因突变情况。结果 1 438例呼吸道感染住院患儿中HBoV阳性333例(23.16%)其中1~5岁患儿HBoV阳性率为46.4%;与对照组健康儿童相比,HBoV阳性患儿白细胞(WBC)、中性粒细胞计数(NEUT)、C-反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α)水平显著升高,差异具有统计学意义(P<0.05);333例HBoV阳性患儿,其中高载量病毒(>10~4 copies/ml)224例,低载量病毒109例,高载量与低载量病毒患儿的呼吸道症状无明显差别,但高载量病毒患儿更容易出现腹泻(P=0.016),更容易引起肺炎(P=0.034);333例HBOV阳性临床标本基因测序,共获得48个全基因序列,其中15个为NP1基因序列,NP1基因236位点(G236A)、447位点(A447G)突变的样本中,病毒载量显著低于未突变的样本,差异具有统计学意义(P<0.05)。结论呼吸道感染患儿中,HBoV阳性率较高,感染患儿易引起肺炎,炎症指标水平升高。某些位点基因突变可能影响病毒基因复制。

Clinical characteristics of children with respiratory tract HBoV infection in Wuhan

OBJECTIVE To investigate the clinical characteristics of hospitalized children with respiratory tract Human Boca virus(HBoV)infection in Wuhan.METHODS Totally 1438 children with respiratory tract infection who were hospitalized in Wuhan Third Hospital from Jan 2017 to Dec 2017 and 310 healthy children were recruited as the study objects.The throat swab specimens were collected from the 1438 children and detected for viral infection by using RT-PCR.The levels of inflammatory indexes were compared between the healthy children and the HBoV-positive children,the clinical symptoms of the HBoV-positive children were analyzed,the throat swab specimens were collected from the HBoV-positive children,the gene sequencing was performed for the amplified products,and the gene mutation was analyzed.RESULTS Of the 1438 hospitalized children with respiratory tract infection,333(23.16%)were positive for HBoV,and the positive rate of HBoV of the children aged between 1 and 5 years old was 46.4%.The levels of white blood cell(WBC),neutrophils(NEUT),C-reactive protein(CRP)and tumor necrosis factor-α(TNF-α)of the HBoV-positive children were significantly higher than those of the healthy children in the control group(P<0.05).Among the 333 HBoV-positive children,224 had high viral load(more than 10^4 copies/ml),and 109 had low viral load;there was no significant difference in the respiratory tract symptom between the high viral load children and the low viral load children,however,the high viral load children were more likely to have diarrhea(P=0.016)and pneumonia(P=0.034).Totally 48 whole genome sequences were obtained from the clinical specimens of the 333 HBoV-positive children through gene sequencing,15 of which were NP1 gene sequences.The viral load was significantly lower in the specimens with mutations in NP1 gene 236 locus(G236 A)and 447 locus(A447 G)than in the specimens without mutations(P<0.05).CONCLUSION The positive rate of HBoV is high among the children with respiratory tract infection,the infection may result in pneumonia and elevation of inflammatory indexes.The gene mutations in some loci may affect the viral gene duplication.