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Acute bronchiolitis is a common paediatric disease of infancy. Its association with subsequent asthma development has puzzled clinicians and epidemiologists for decades. This article reviews the current state of knowledge regarding the role of acute bronchiolitis in the inception of asthma. There is little doubt that acute bronchiolitis is associated with an increased risk of recurrent wheezing throughout the primary school years although the direction of causality—i.e. whether bronchiolitis in infancy leads to asthma or it merely represents the first clinical presentation of predisposition to asthma—is uncertain. Existing evidence suggests that both host factors (e.g. prematurity, atopic predisposition) and acute viral infection characteristics (e.g. type of virus, severity) are operating in this relationship, perhaps with variable involvement in different individuals. Further clarification of these issues will help paediatricians provide evidence‐based information regarding the long‐term prognosis of this common disease to the families, and at the same time, it will facilitate prophylactic approaches and therapeutic strategies.  相似文献   
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目的 探讨呼吸道合胞病毒感染所致的急性毛细支气管炎婴幼儿血清IL-4、IL-8和外周血T淋巴细胞亚群的变化。方法 选取2014年3月—2018年6月广西壮族自治区南溪山医院儿科呼吸道合胞病毒感染的急性毛细支气管炎患儿142例,按疾病严重程度分为轻度组、中度组和重度组,每组再分为≤6个月亚组和>6个月亚组。另选取健康婴幼儿(11例)和排除感染的住院术前准备婴幼儿(26例)共37例设为对照组。观察各组血清IL-4和IL-8的变化及外周血T淋巴细胞亚群相对比例变化情况。结果 重度组的IL-4、IL-8水平在≤6个月亚组和>6个月亚组中最高,与其他组比较,差异有统计学意义(P?<0.05)。重度组CD3+CD4+T淋巴细胞比值高于其他组,其中≤6个月亚组最高;重度组CD3+CD8+和CD3+CD56+T淋巴细胞比值低于其他组,其中≤6个月亚组最低,与其他组比较,差异有统计学意义(P?<0.05)。结论 呼吸道合胞病毒感染所致毛细支气管炎患儿月龄和疾病程度的不同,对血清IL-4和IL-8水平及外周血T淋巴细胞亚群具有影响。  相似文献   
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Aspergillus colonization after lung transplantation may increase the risk for bronchiolitis obliterans syndrome (BOS), a disease of small airways. We hypothesized that colonization with small conidia Aspergillus species would be associated with a greater risk of BOS, based upon an increased likelihood of deposition in small airways. We studied adult primary lung recipients from two large centers; 298 recipients at University of California, Los Angeles and 482 recipients at Duke University Medical Center. We grouped Aspergillus species by conidia diameter ≤3.5 μm. We assessed the relationship of colonization with outcomes in Cox models. Pre‐BOS colonization with small conidia Aspergillus species, but not large, was a risk factor for BOS (p = 0.002, HR 1.44, 95% CI 1.14–1.82), along with acute rejection, single lung and Pseudomonas. Colonization with small conidia species also associated with risk of death (p = 0.03, HR 1.30, 95% CI 1.03–1.64). Although other virulence traits besides conidia size may be important, we have demonstrated in two large independent cohorts that colonization with small conidia Aspergillus species increases the risk of BOS and death. Prospective evaluation of strategies to prevent Aspergillus colonization of small airways is warranted, with the goal of preserving lung allograft function as long as possible.  相似文献   
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It is plausible that infections post‐hematopoietic SCT play a role in the pathogenesis of BOS. A prospective study for children with history, questionnaire, examination, PFTs, and blood counts at one, three, six, nine, 12, 18, and 24 months post‐SCT was conducted. Between September 2009 and September 2011 (n = 39), six developed BOS at 200 days (range 94–282), three patients had probable clinical respiratory infection, and all six had higher neutrophil count compared to non‐BOS patients (4.7 vs. 2.4 at three months and 6.3 vs. 2.9 at six months ×109/L, p = 0.03). Contribution of clinical and subclinical infection needs to be considered in the pathogenesis of BOS.  相似文献   
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