Duff A L, Pomeranz E S, Gelber L E, Price G W, Farris H, Hayden F G, Platts-Mills T A, Heymann P W
Department of Pediatrics, University of Virginia Health Sciences Center, Charlottesville 22908.
Pediatrics. 1993 Oct;92(4):535-40.
To examine the prevalence of viral infection, passive smoke exposure, and IgE antibody to inhaled allergens in infants and children treated for acute wheezing.
Case-control study of actively wheezing children who were compared with children without respiratory tract symptoms.
University of Virginia Pediatric Emergency Room.
Convenience sample of 99 wheezing patients (2 months to 16 years of age) and 57 control patients (6 months to 16 years of age).
Serum IgE antibody to inhalant allergens, measured by radioallergosorbent test (RAST), was uncommon in wheezing and control patients under age 2. After 2 years of age, the percentage of RAST-positive patients increased markedly and was significantly higher in wheezing patients than controls after age 4 (72%, n = 54, and 30%, n = 40, respectively, P < .001). Total IgE levels and nasal eosinophilia were strongly correlated with a positive RAST after age 2. Viral pathogens, predominantly respiratory syncytial virus, were identified in nasal washes from 70% (n = 20) of wheezing patients younger than 2 years of age compared with 20% of controls (n = 10), P < .05. After age 2, viruses, particularly rhinovirus, were isolated in washes from 31% (n = 70) of wheezing patients, 64% of whom were also RAST-positive. Levels of cotinine, a nicotine metabolite, were elevated (> or = 10 ng/mL) in saliva from a large percentage of smoke-exposed, wheezing patients under 2 (74%, n = 19) compared with those over 2 (14%, n = 51), P < .001. Odds ratios for wheezing were significant for virus (8.2, confidence interval [CI] = 1.3 to 5.0), and cotinine (4.7, CI = 1.0 to 21.3) in children under 2, and IgE antibody by RAST (4.5, CI = 2.0 to 10.2), virus (3.7, CI = 1.3 to 10.6), and the combination of IgE antibody and virus (10.8, CI = 1.9 to 59.0) were significant risk factors after age 2.
Wheezing children younger than 2 years of age had a high rate of viral infection and a low rate of IgE antibody to inhalant allergens. When these children were exposed to passive smoke, salivary cotinine levels were elevated suggesting heavy exposure. After 2 years of age, sensitization to inhaled allergens became increasingly important and viruses remained a significant risk factor for wheezing. These data support recommendations to reduce tobacco smoke exposure at home, especially for young patients, and to consider sensitization to inhaled allergens and allergen avoidance in wheezing children at an early age, particularly after age 2 years.
研究接受急性喘息治疗的婴幼儿及儿童中病毒感染、被动吸烟暴露情况以及针对吸入性过敏原的IgE抗体情况。
对正在喘息的儿童与无呼吸道症状的儿童进行病例对照研究。
弗吉尼亚大学儿科急诊室。
选取99例喘息患者（年龄2个月至16岁）和57例对照患者（年龄6个月至16岁）作为便利样本。
通过放射变应原吸附试验（RAST）检测，2岁以下喘息患者和对照患者中针对吸入性过敏原的血清IgE抗体并不常见。2岁以后，RAST阳性患者的比例显著增加，4岁以后喘息患者中的该比例明显高于对照患者（分别为72%，n = 54；30%，n = 40，P <.001）。2岁以后，总IgE水平和鼻嗜酸性粒细胞增多与RAST阳性密切相关。在2岁以下的喘息患者中，70%（n = 20）的鼻腔冲洗液中检出病毒病原体，主要为呼吸道合胞病毒，而对照患者中这一比例为20%（n = 10），P <.05。2岁以后，31%（n = 70）的喘息患者的冲洗液中分离出病毒，尤其是鼻病毒，其中64%同时RAST阳性。与2岁以上的喘息患者（14%，n = 51）相比，2岁以下大量暴露于烟雾中的喘息患者唾液中可替宁（一种尼古丁代谢产物）水平升高（≥10 ng/mL），P <.001。2岁以下儿童中，病毒（优势比8.2，置信区间[CI]=1.3至5.0）和可替宁（优势比4.7，CI = 1.0至21.3）与喘息显著相关；2岁以后，RAST检测的IgE抗体（优势比4.5，CI = 2.0至10.2）、病毒（优势比3.7，CI = 1.3至10.6）以及IgE抗体与病毒联合（优势比10.8，CI = 1.9至59.0）均为显著的危险因素。
2岁以下喘息儿童病毒感染率高，针对吸入性过敏原的IgE抗体率低。当这些儿童暴露于被动吸烟环境时，唾液中可替宁水平升高提示暴露严重。2岁以后，对吸入性过敏原的致敏作用变得越来越重要，病毒仍然是喘息的重要危险因素。这些数据支持在家中减少烟草烟雾暴露的建议，特别是对于年幼患者，并建议在喘息儿童早期，尤其是2岁以后，考虑对吸入性过敏原的致敏情况并避免接触过敏原。
