School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, UK.
Thorax. 2011 Jul;66(7):579-84. doi: 10.1136/thx.2010.137281. Epub 2011 Jan 26.
Anaerobic bacteria are increasingly regarded as important in cystic fibrosis (CF) pulmonary infection. The aim of this study was to determine the effect of antibiotic treatment on aerobic and anaerobic microbial community diversity and abundance during exacerbations in patients with CF.
Sputum was collected at the start and completion of antibiotic treatment of exacerbations and when clinically stable. Bacteria were quantified and identified following culture, and community composition was also examined using culture-independent methods.
Pseudomonas aeruginosa or Burkholderia cepacia complex were detected by culture in 24/26 samples at the start of treatment, 22/26 samples at completion of treatment and 11/13 stable samples. Anaerobic bacteria were detected in all start of treatment and stable samples and in 23/26 completion of treatment samples. Molecular analysis showed greater bacterial diversity within sputum samples than was detected by culture; there was reasonably good agreement between the methods for the presence or absence of aerobic bacteria such as P aeruginosa (κ=0.74) and B cepacia complex (κ=0.92), but agreement was poorer for anaerobes. Both methods showed that the composition of the bacterial community varied between patients but remained relatively stable in most individuals despite treatment. Bacterial abundance decreased transiently following treatment, with this effect more evident for aerobes (median decrease in total viable count 2.3×10(7) cfu/g, p=0.005) than for anaerobes (median decrease in total viable count 3×10(6) cfu/g, p=0.046).
Antibiotic treatment targeted against aerobes had a minimal effect on abundance of anaerobes and community composition, with both culture and molecular detection methods required for comprehensive characterisation of the microbial community in the CF lung. Further studies are required to determine the clinical significance of and optimal treatment for these newly identified bacteria.
厌氧菌在囊性纤维化（CF）肺部感染中越来越受到重视。本研究旨在确定抗生素治疗对 CF 患者加重期需氧和厌氧微生物群落多样性和丰度的影响。
在抗生素治疗加重期开始时和结束时以及临床稳定时采集痰液。经培养后定量和鉴定细菌，并使用非培养方法检查群落组成。
在治疗开始时，24/26 个样本中培养出铜绿假单胞菌或洋葱伯克霍尔德菌复合菌，在治疗结束时，22/26 个样本中，在 11/13 个稳定样本中检测到。在所有开始治疗和稳定样本中均检测到厌氧菌，在 23/26 个完成治疗的样本中也检测到厌氧菌。分子分析显示痰样本中的细菌多样性高于培养法检测到的多样性；培养法和分子法在检测需氧菌（如铜绿假单胞菌，κ=0.74；洋葱伯克霍尔德菌复合菌，κ=0.92）的存在或不存在方面具有较好的一致性，但在检测厌氧菌方面一致性较差。两种方法均显示，细菌群落的组成在患者之间存在差异，但在大多数个体中仍相对稳定，尽管进行了治疗。治疗后细菌丰度短暂下降，这种影响在需氧菌中更为明显（总活菌计数中位数下降 2.3×10(7)cfu/g，p=0.005），而在厌氧菌中则不太明显（总活菌计数中位数下降 3×10(6)cfu/g，p=0.046）。
针对需氧菌的抗生素治疗对厌氧菌的丰度和群落组成影响较小，需要培养和分子检测方法来全面描述 CF 肺部的微生物群落。需要进一步研究以确定这些新鉴定细菌的临床意义和最佳治疗方法。
