Carbapenem-resistant Enterobacteriaceae (CRE) that produce Klebsiella pneumoniae carbapenemase (KPC) are increasingly reported worldwide and have become more and more resistant to nearly all antibiotics during the past decade. The emergence of Klebsiella pneumoniae strains with decreased susceptibility to carbapenems, which are used as a last resort treatment option, is a significant threat to hospitalized patients worldwide as K. pneumoniae infection is responsible for a high mortality rate in the elderly and immunodeficient individuals. This study used Lactobacillus fermentum as a candidate probiotic for treating CRE-related infections and investigated its effectiveness. We treated mice with L. fermentum originating from the vaginal fluid of a healthy Korean woman and evaluated the Lactobacilli's efficacy in preventive, treatment, non-establishment, and colonization mouse model experiments. Compared to the control, pre-treatment with L. fermentum significantly reduced body weight loss in the mouse models, and all mice survived until the end of the study. The oral administration of L. fermentum after carbapenem-resistant Klebsiella (CRK) infection decreased mortality and illness severity during a 2-week observation period and showed that it affects other strains of CRK bacteria. Also,the number of Klebsiella bacteria was decreased to below 5.5 log₁₀ CFU/ml following oral administration of L. fermentum in the colonization model. These findings demonstrate L. fermentum's antibacterial activity and its potential to treat CRE infection in the future.

中文翻译：

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从健康女性阴道分离的发酵乳杆菌对体内耐碳青霉烯类克雷伯氏菌感染的疗效。

产生肺炎克雷伯菌碳青霉烯酶 (KPC) 的碳青霉烯类耐药肠杆菌科(CRE)在世界范围内的报道越来越多，并且在过去十年中对几乎所有抗生素的耐药性越来越强。肺炎克雷伯菌菌株的出现对碳青霉烯类药物的敏感性降低，被用作最后的治疗选择，对全世界住院患者构成重大威胁，因为肺炎克雷伯菌感染是导致老年人和免疫缺陷个体高死亡率的原因。本研究使用发酵乳杆菌作为治疗 CRE 相关感染的候选益生菌，并研究了其有效性。我们用 L. fermentum源自一名健康的韩国女性的阴道液，并评估了Lactobacilli在预防、治疗、非建立和定植小鼠模型实验中的功效。与对照组相比，用L. fermentum预处理显着减少了小鼠模型的体重减轻，并且所有小鼠都存活到研究结束。在 2 周的观察期内，耐碳青霉烯类克雷伯菌(CRK) 感染后口服发酵乳杆菌降低了死亡率和疾病严重程度，并表明它影响其他 CRK 细菌菌株。此外，克雷伯氏菌的数量减少到 5.5 log _10以下在定植模型中口服发酵乳杆菌后的 CFU/ml。这些发现证明了L. fermentum的抗菌活性及其在未来治疗 CRE 感染的潜力。