Abstract：
BACKGROUND: The objective of this study was to study the effect of Klebsiella-specific phage isolated from sewage with and without the combination of antibiotics (imipenem) on the growth of clinical isolates of multidrug-resistant Klebsiella pneumoniae by time-kill assay and also to study the effect of bacteriophage and bacteriophage-antibiotic (imipenem) combination on biofilm production.
METHODS: A total of 40 MDR K. pneumoniae isolates were used. Klebsiella-specific phage was isolated using K. pneumoniae subspp. pneumoniae ATCC 33495 as the host from sewage. In vitro time kill curve assays were performed to evaluate the effect of Klebsiella-specific phage with and without the combination of antibiotics on the viable cell counts of MDR K. pneumoniae isolates. Microtiter plate method of O\'Toole and Kolter was used to study the effect of Klebsiella-specific phage with and without the combination of antibiotics on biofilm production. For the Time kill assay, results were analyzed for significant differences using Friedman test. Tests for significant differences between the different groups were found using the Mann-Whitney U test. The correlation between the formation of biofilm was analyzed using Karl Pearson\'s coefficient of correlation. P value of <0.05 was considered to be statistically significant.
RESULTS: In vitro time-kill assay showed a 0.4 log decline and a 0.5 log decline in K. pneumoniae colony counts at 4 h, when phage was administered individually and in combination with imipenem, respectively (p < 0.001). Phage and phage-imipenem combinations reduced the ability of K. pneumoniae to produce biofilm by 38 % and 53 %, respectively.
CONCLUSIONS: In conclusion, this study suggests that phage therapy has inhibiting activity against MDR K. pneumoniae. It is found to reduce bacterial cell count and biofilm formation but does not have a total cidal effect. However, in order to get a notable result, a phage cocktail or combination of phage with other antibiotic(s) is suggested.
METHODS: A total of 40 MDR K. pneumoniae isolates were used. Klebsiella-specific phage was isolated using K. pneumoniae subspp. pneumoniae ATCC 33495 as the host from sewage. In vitro time kill curve assays were performed to evaluate the effect of Klebsiella-specific phage with and without the combination of antibiotics on the viable cell counts of MDR K. pneumoniae isolates. Microtiter plate method of O\'Toole and Kolter was used to study the effect of Klebsiella-specific phage with and without the combination of antibiotics on biofilm production. For the Time kill assay, results were analyzed for significant differences using Friedman test. Tests for significant differences between the different groups were found using the Mann-Whitney U test. The correlation between the formation of biofilm was analyzed using Karl Pearson\'s coefficient of correlation. P value of <0.05 was considered to be statistically significant.
RESULTS: In vitro time-kill assay showed a 0.4 log decline and a 0.5 log decline in K. pneumoniae colony counts at 4 h, when phage was administered individually and in combination with imipenem, respectively (p < 0.001). Phage and phage-imipenem combinations reduced the ability of K. pneumoniae to produce biofilm by 38 % and 53 %, respectively.
CONCLUSIONS: In conclusion, this study suggests that phage therapy has inhibiting activity against MDR K. pneumoniae. It is found to reduce bacterial cell count and biofilm formation but does not have a total cidal effect. However, in order to get a notable result, a phage cocktail or combination of phage with other antibiotic(s) is suggested.
摘要：
背景：这项研究的目的是研究从污水中分离的克雷伯菌特异性噬菌体，有和没有抗生素（亚胺培南）的组合对多药耐药肺炎克雷伯菌临床分离株生长的影响时间-杀死试验，并研究噬菌体和噬菌体-抗生素（亚胺培南）组合对生物膜产生的影响。
方法：共使用40株MDR肺炎克雷伯菌。使用肺炎克雷伯菌亚种分离克雷伯菌特异性噬菌体。肺炎杆菌ATCC33495作为宿主来自污水。进行体外时间杀伤曲线测定以评估有和没有抗生素组合的克雷伯菌属特异性噬菌体对MDR肺炎克雷伯菌分离株的活细胞计数的影响。使用O'Toole和Kolter的微量滴定板法研究了有和没有抗生素组合的克雷伯菌特异性噬菌体对生物膜产生的影响。对于时间杀伤分析，结果采用Friedman检验进行显著性差异分析。使用Mann-WhitneyU检验发现了不同组之间的显着差异。使用KarlPearson相关系数分析生物膜形成之间的相关性。P值<0.05被认为具有统计学意义。
结果：体外时间杀伤试验显示，在4小时时，肺炎克雷伯菌菌落计数下降0.4对数，下降0.5对数，当噬菌体单独和与亚胺培南联合施用时，分别(p<0.001)。噬菌体和噬菌体-亚胺培南组合可将肺炎克雷伯菌产生生物膜的能力降低38％和53％，分别。
结论：结论：这项研究表明，噬菌体疗法具有抑制MDR肺炎克雷伯菌的活性。发现其减少细菌细胞计数和生物膜形成,但不具有总的杀灭效果。然而,为了获得显著的结果，建议使用噬菌体混合物或噬菌体与其他抗生素的组合。
方法：共使用40株MDR肺炎克雷伯菌。使用肺炎克雷伯菌亚种分离克雷伯菌特异性噬菌体。肺炎杆菌ATCC33495作为宿主来自污水。进行体外时间杀伤曲线测定以评估有和没有抗生素组合的克雷伯菌属特异性噬菌体对MDR肺炎克雷伯菌分离株的活细胞计数的影响。使用O'Toole和Kolter的微量滴定板法研究了有和没有抗生素组合的克雷伯菌特异性噬菌体对生物膜产生的影响。对于时间杀伤分析，结果采用Friedman检验进行显著性差异分析。使用Mann-WhitneyU检验发现了不同组之间的显着差异。使用KarlPearson相关系数分析生物膜形成之间的相关性。P值<0.05被认为具有统计学意义。
结果：体外时间杀伤试验显示，在4小时时，肺炎克雷伯菌菌落计数下降0.4对数，下降0.5对数，当噬菌体单独和与亚胺培南联合施用时，分别(p<0.001)。噬菌体和噬菌体-亚胺培南组合可将肺炎克雷伯菌产生生物膜的能力降低38％和53％，分别。
结论：结论：这项研究表明，噬菌体疗法具有抑制MDR肺炎克雷伯菌的活性。发现其减少细菌细胞计数和生物膜形成,但不具有总的杀灭效果。然而,为了获得显著的结果，建议使用噬菌体混合物或噬菌体与其他抗生素的组合。
