Iapichino Gaetano, Callegari Maria Luisa, Marzorati Silvia, Cigada Marco, Corbella Davide, Ferrari Susanna, Morelli Lorenzo
Istituto di Anestesiologia e Rianimazione, Università degli Studi, Polo San Paolo, via Di Rudinì 8, I-20142 Milano, Italy.
Centro Ricerche Biotecnologiche, Università Cattolica del Sacro Cuore, Via Milano 24, 26100 Cremona, Italy.
J Med Microbiol. 2008 Aug;57(Pt 8):1007-1014. doi: 10.1099/jmm.0.47387-0.
We evaluated the relationship between the intestinal microbiota composition and clinical outcome in a group of 15 high-risk patients admitted for acute infection and/or surgical/accidental trauma who were treated with systemic antibiotics according to standard intensive care unit (ICU) protocols. There was a high mortality rate amongst these patients, each of whom had a considerable organ failure score at admission, respiratory assistance during the most of their ICU stay and a long length of stay. All of these individuals received sedation and enteral nutrition, and the majority also received insulin, vasoactive drugs and some stress-ulcer prophylaxis agents. The intestinal microbiota composition was assessed using denaturing gradient gel electrophoresis (DGGE), a molecular biology tool used to characterize bacterial ecosystems. As all of the patient subjects were in good health prior to their acute illness and admission to the ICU, the first faecal samples obtained from this group showed a DGGE banding pattern that was similar to that of healthy subjects. After 1 week of critical illness, coupled with intensive care treatment, including antibiotics, a very definite alteration in the overall microbiota composition was evident, as revealed by a reduction in the number of DGGE bands. Further pronounced changes to the DGGE banding profiles could be observed in patients remaining in the ICU for 2 weeks. Moreover, a dominant band, identified by sequencing as highly related to Enterococcus, was detected in the DGGE profile of some of our patient subjects. We also performed real-time PCR and obtained results that were in agreement with our qualitative evaluations using DGGE. The degree of organ failure and ICU mortality was significantly higher in patients for whom a high reduction in microbiota biodiversity was coupled with a massive presence of enterococci. A statistically significant link between these two ecological traits and the use of clindamycin was also found.
我们评估了15名因急性感染和/或手术/意外创伤入院的高危患者的肠道微生物群组成与临床结局之间的关系，这些患者按照标准重症监护病房（ICU）方案接受了全身抗生素治疗。这些患者的死亡率很高，每位患者入院时器官衰竭评分都相当高，在大部分ICU住院期间都需要呼吸支持，且住院时间很长。所有这些患者均接受了镇静和肠内营养，大多数还接受了胰岛素、血管活性药物和一些应激性溃疡预防药物。使用变性梯度凝胶电泳（DGGE）评估肠道微生物群组成，DGGE是一种用于表征细菌生态系统的分子生物学工具。由于所有患者在急性疾病和入住ICU之前身体健康，从该组患者获得的首批粪便样本显示出与健康受试者相似的DGGE条带模式。在危重病1周后，加上包括抗生素在内的重症监护治疗，总体微生物群组成出现了非常明显的变化，表现为DGGE条带数量减少。在ICU住院2周的患者中，可以观察到DGGE条带图谱有进一步明显的变化。此外，在我们部分患者的DGGE图谱中检测到一条优势条带，经测序鉴定与肠球菌高度相关。我们还进行了实时PCR，获得的结果与我们使用DGGE的定性评估结果一致。微生物群生物多样性大幅降低且肠球菌大量存在的患者，其器官衰竭程度和ICU死亡率显著更高。还发现这两个生态特征与克林霉素的使用之间存在统计学上的显著关联。
