Department of Dietetics and Nutritional Science, Harokopio University, Kallithea, Greece.
Benef Microbes. 2010 Sep;1(3):297-306. doi: 10.3920/BM2010.0007.
Increasing use of antibiotics for the treatment of infectious diseases and also for non-therapeutic reasons (agriculture, animal husbandry and aquaculture) has led to the increasing incidence of antibiotic resistance and the ineffectiveness of antimicrobial treatment. Commensal intestinal bacteria are very often exposed to the selective pressure of antimicrobial agents and may constitute a reservoir of antibiotic resistance determinants that can be transferred to pathogens. The present study aimed to investigate the antibiotic susceptibility profile and the presence of selected resistance genes in cocci isolated from the faecal microbiota of 35 healthy, full-term infants at 4, 30 and 90 days after delivery. A total of 148 gram-positive, catalase-negative cocci were isolated and tested for susceptibility to 12 different antibiotics by disk-diffusion technique. Multiplex PCR analysis was performed for the identification of Enterococcus spp. isolates and the simultaneous detection of vancomycin-resistance genes. PCR-based methodology was used also for identification of tetracycline and erythromycin resistance determinants. Identification results indicated E. faecalis as the predominant species (81 strains), followed by E. faecium, E. casseliflavus/E. flavescens and E. gallinarum. High prevalence of resistance to tetracycline (39.9%), erythromycin (35.1%), vancomycin (19.6%) and to nucleic acid synthesis inhibitors was detected. PCR data revealed 24 out of 52 erythromycin-resistant isolates carrying the ermB gene and 32 out of 59 tetracycline-resistant strains carrying tet genes, with tet(L) determinant being the most frequently detected. Only intrinsic vancomycin resistance (vanC1 and vanC2/C3) was reported among tested isolates. In conclusion, erythromycin and tetracycline acquired resistant traits are widespread among faecal cocci isolates from Greek, healthy infants under no apparent antimicrobial selective pressure.
由于抗生素被越来越多地用于治疗传染病以及非治疗性目的（农业、畜牧业和水产养殖业），导致抗生素耐药性的发生率不断增加，抗菌治疗效果下降。肠道共生菌经常受到抗菌药物的选择压力，可能成为抗生素耐药决定因素的储库，这些决定因素可转移至病原体。本研究旨在调查从分娩后 4、30 和 90 天的 35 名健康足月婴儿的粪便微生物群中分离的球菌对抗生素的敏感性，并检测其对 12 种不同抗生素的敏感性。采用纸片扩散法检测 148 株过氧化氢阴性革兰阳性球菌的药敏谱，并对肠球菌属进行鉴定和同时检测万古霉素耐药基因。采用多重 PCR 技术鉴定屎肠球菌和粪肠球菌，并同时检测万古霉素耐药基因。还采用基于 PCR 的方法检测四环素和红霉素耐药决定因素。鉴定结果表明，以屎肠球菌（81 株）为主，其次是粪肠球菌、屎肠球菌/中间肠球菌和鸡肠球菌。对四环素（39.9%）、红霉素（35.1%）、万古霉素（19.6%）和核酸合成抑制剂的耐药率较高。PCR 数据显示，52 株红霉素耐药株中有 24 株携带 ermB 基因，59 株四环素耐药株中有 32 株携带 tet 基因，其中 tet(L) 决定子最常见。在测试的分离株中仅报告了固有万古霉素耐药（vanC1 和 vanC2/C3）。总之，在没有明显抗菌选择压力的情况下，来自希腊健康婴儿粪便球菌分离株中广泛存在获得性红霉素和四环素耐药性。
