上海地区儿童急性下呼吸道常见病毒及鼻病毒感染的临床研究

Common virus and rhinovirus infection in acute lower respiratory tract diseases of children in Shanghai

目的了解上海地区急性下呼吸道感染(ALRTI)患儿病毒感染病原体的现状。方法收集2005年1月至12月住院确诊为ALRTI的342例患儿深部鼻咽分泌物(NPS)标本,建立套式RT-PCR的方法测定NPS中的鼻病毒(HRV)基因,用直接免疫荧光法(DFA)检测NPS中的呼吸道合胞病毒(RSV)、流感病毒(IFV)、副流感病毒(PIV)、腺病毒(ADV)抗原,对各种病毒在小儿ALRTI中的流行特点及临床特征进行分析。结果342例ALRTI患儿NPS标本中,检测到HRV阳性46例(13.45%)。HRV阳性患儿中,3岁以下婴幼儿38例(82.6%),1岁以下27例(58.7%)。HRV致ALRTI全年可见,3到5月份为最高峰。RSV阳性64例(18.70%),1岁以下46例(71.88%)。1岁以下与1岁以上患儿RSV的检出率比较差异有统计学意义(χ2=4.03,P<0.05)。RSV的检出阳性率从2月份起逐渐下降,6到7月份达到最低,8月份起检出率逐渐升高,至12月份达到最高。ADV感染9例(2.63%),PIV感染8例(2.30%),IFV感染7例(2.0%)。本组患儿病毒混合感染共4例。130例病毒性ALRTI患儿诊断支气管肺炎122例,体温正常42例、低热34例、中度热50例、高热仅4例,以中度发热以下为主,末梢血白细胞<10×109/L93例(71.5%),中性粒细胞<50%94例(72.3%),CRP<8mg/L99例(76.2%),均符合病毒性肺炎的特点。64例RSV感染病例中有30例合并喘息(46.9%),36例HRV感染病例中24例合并喘息(52.2%)。结论病毒病原在上海地区小儿ALRTI中占有重要地位,小儿病毒性ALRTI以RSV及HRV为主,ADV、PIV及IFV相对少见,混合性病毒感染少见。HRV所致小儿ALRTI以3岁以下儿童多见,尤以1岁以下为多。上海地区HRV感染主要集中于春秋两季。RSV所致小儿ALRTI以1岁以下为主,以秋、冬、春气温较低的季节多发。除RSV外,HRV也是导致ALRTI患儿喘息的重要病原。

Objectives To study the viral etiology of acute lower respiratory tract infection （ALRTI） of children in Shanghai. Methods Three hundred and forty-two nasopharyngeal secretion （NPS） samples were collected from ALRTI children who were hospitalized between January to December 2005. Nested RT-PCR was used to detect the expression of human rhinovirus （HRV） genes in NPS. Direct immnofluorescence assay （DFA） was used to identify 7 different virus strains, including respiratory syncytial virus （RSV）, influenza virus （IFV） type A and B, parainfluenza virus （PIV） type 1, 2, 3 and adenovirus （ADV） . Viral epidemiological data were analyzed. The correlations of virus infections and clinical characteristics were also investigated. Results Forty-six （ 13.45% ） out of 342 samples were HRV positive. Among them, 38 （82.6%） children were below 3 years old; 27 （58.7%） were below 12 months old. The prevalence of HRV infection in ALRTI was detected year round and peaked from March to May. Among 64 （18.70%） cases with positive RSV, 46 （71.88%） children were below 1 year old. There was significant difference of RSV prevalence between children below and above 1 year old （X^2 = 4.03, P 〈0.05） . The detection rate of RSV decreased from February to July to reach its lowest point and began to increase from August and reached its highest point in December. Nine cases （2.63%） were ADV positive; 8 （2.3%） PIV positive and 7 （2.0%） IFV positive. Overlapping infection of 2 kinds of virus was only found in 4 cases. In 130 cases of ALRTI caused by viral infection, bronchitis was detected in 122 cases. Body temporature was found to be normal （42 cases）, low grade fever （34 cases）, medium fever （50 cases） and high fever （4 cases） with majority below medium fever. Peripherial blood white cells 〈10×10^9/L were detected in 93 cases （71.5%）, neutrophils 〈 50% in 94 cases （72.3%）, CRP 〈 8 mg/L in 99 cases （76.2%） . These clinical features matched with the characteristics of viral pneumonia. Among 64 cases with RSV infection, 30 patients （46.9%） gasped while 24 patients （52.2%） gasped among 36 HRV-positive patients. Conclusions Viral infection plays an important role in children with ALRTI in Shanghai. RSV and HRV were two main virus strains responsible, while ADV, PIV and IFV were not common in Shanghai. Mixed viral infections were few. The incidence of HRV infection predominates in children under 3 years old and especially under 1 year old. HRV infection occurs mainly in spring and autumn. RSV infection was popular in children below 1 year old and occurred in spring, autumn and winter. Other than RSV, HRV was also an important pathogen causing asthma.