Thorax：呼吸道菌群与支气管扩张患者的疾病严重程度相关

对于非囊性纤维化（CF）支气管扩张成人患者而言，感染在疾病进展中发挥着潜在的重要作用。尽管感染在成人非囊性纤维化（CF）支气管扩张疾病进展中有潜在的重要作用，然而对于这些患者下呼吸道的菌群特点的描述却很少。针对这种情况，来自伦敦大学国王学院医药科学研究所的Kenneth Bruce博士等人进行了一项研究，研究结果在线发表于2013年4月6日的《胸部》(Thorax)杂志上。作者发现非CF支气管扩张的成年患者下呼吸道微生物的特征与疾病严重程度的临床指标显着相关。

该研究从41名成年非CF支气管扩张患者获取配对的诱导痰和支气管肺泡灌洗样本，并通过16S核糖体RNA基因焦磷酸测序进行分析。对那些与呼吸道感染和更普遍的机会性感染相关的140种细菌进行鉴定，发现菌群分布特征与疾病的临床指标密切相关。在这组患者中通过评估不同菌种的分布和传播特点分别定义为"核心"和"卫星"菌落。将常规能检测到和高丰度的菌种定义为一组核心菌群。核心菌群包括那些目前与支气管扩张感染相关的细菌，如铜绿假单胞菌，流感嗜血杆菌和肺炎链球菌，和许多不能通过标准的诊断检测报告的菌种。

研究结果表明，无论是用药前还是用药后的支气管扩张患者的菌落多样性与第一秒用力呼气量（FEV1）呈显著的正相关。此外相似的菌落组成与FEV1，中性粒细胞计数和Leicester咳嗽评分显著相关。

该研究发现，在非CF支气管扩张的成年患者下呼吸道菌群的多样性与第一秒用力呼气量（FEV1）呈显著的正相关，这与前期其他研究的报道相似。此前曾有人认为，患者的 FEV1，中性粒细胞计数和Leicester咳嗽评分与呼吸道菌落相关，对此该研究予以确认并进行了延伸。然而该项研究并没有去除结核、真菌等潜在致病菌，也没有证实菌落与疾病恶化等临床重要事件的关系。

Clinical measures of disease in adult non-CF bronchiectasis correlate with airway microbiota composition.
RATIONALE
Despite the potentially important roles for infection in adult non-cystic fibrosis (CF) bronchiectasis disease progression, the bacterial species present in the lower airways of these patients is poorly characterised.
OBJECTIVES
To provide a comprehensive cross-sectional analysis of bacterial content of lower airway samples from patients with non-CF bronchiectasis using culture-independent microbiology.
METHODS
Paired induced sputum and bronchoalveolar lavage samples, obtained from 41 adult patients with non-CF bronchiectasis, were analysed by 16S ribosomal RNA gene pyrosequencing. Assessment of species distribution and dispersal allowed 'core' and 'satellite' bacterial populations to be defined for this patient group. Microbiota characteristics correlated with clinical markers of disease.
MEASUREMENT AND MAIN RESULTS
140 bacterial species were identified, including those associated with respiratory tract infections and opportunistic infections more generally. A group of core species, consisting of species detected frequently and in high abundance, was defined. Core species included those currently associated with infection in bronchiectasis, such as Pseudomonas aeruginosa, Haemophilus influenzae and Streptococcus pneumoniae, and many species that would be unlikely to be reported through standard diagnostic surveillance. These included members of the genera Veillonella, Prevotella and Neisseria. The comparative contribution of core and satellite groups suggested a low level of random species acquisition. Bacterial diversity was significantly positively correlated with forced expiratory volume in 1 s (FEV1) and bacterial community composition similarity correlated significantly with FEV1, neutrophil count and Leicester cough score.
CONCLUSIONS
Characteristics of the lower airways microbiota of adult patients with non-CF bronchiectasis correlate significantly with clinical markers of disease severity.