Benito Daniel, Lozano Carmen, Rezusta Antonio, Ferrer Isabel, Vasquez Maria Alejandra, Ceballos Sara, Zarazaga Myriam, Revillo Maria José, Torres Carmen
Area de Bioquímica y Biología Molecular, Universidad de La Rioja, Logroño, Spain.
Servicio de Microbiología, Hospital Universitario Miguel Servet, IIS Aragón, Zaragoza, Spain; Universidad de Zaragoza, Zaragoza, Spain.
Int J Med Microbiol. 2014 Nov;304(8):1226-32. doi: 10.1016/j.ijmm.2014.09.004. Epub 2014 Sep 26.
Tetracycline-resistance (Tet(R)) has been postulated as a marker of the livestock-associated methicillin-resistant Staphylococcus aureus (MRSA) lineage CC398.
to determine the spa-types and assigned MLST clonal complexes (CCs) among all 98 MRSA-Tet(R) strains recovered during 2011-2012 (from different patients) in a Spanish Hospital, analyzing the possible correlation with livestock-contact of the patients. All 98 strains were assigned to 9 CCs: CC398 (60.2%), CC1 (19.4%), CC5 (12.2%), and other CCs (8.2%). The 98 patients were classified into three groups: (A) contact with livestock-animals (n=25); (B) no-contact with livestock-animals (n=42); (C) no information about animal contact (n=31). A significant higher percentage of CC398 strains was obtained in group A (76%) than in group B (50%) (p<0.05), being the percentage in group C of 61.3%. Most of MRSA-Tet(R)-CC398 strains presented a multi-resistance phenotype, including erythromycin, clindamycin, and ciprofloxacin, and the most prevalent detected genes were tet(M) and erm(C). Three strains presented the phenotype macrolide-susceptibility/lincosamide-resistance and contained the vga(A) gene. MRSA-CC1 strains showed higher percentages of erythromycin/clindamycin resistance (95%/89%) than MRSA-CC398 strains (58%/63%), and this resistance was usually mediated by erm(C) gene. Most of MRSA-CC5 strains showed resistance to ciprofloxacin, tobramycin/kanamycin and erythromycin. None of the strains presented the genes lukF/lukS-PV, tsst-1, eta, etb or etd. All MRSA-CC398 strains lacked the genes of the immune-evasion-cluster, but MRSA-CC1 strains carried these genes (type E). In conclusion, although MRSA CC398 is detected in a significant higher proportion in patients with livestock-contact; its detection in people without this type of contact also indicates its capacity for human-to-human transmission.
四环素抗性（Tet(R)）已被假定为与家畜相关的耐甲氧西林金黄色葡萄球菌（MRSA）谱系CC398的一个标志物。
确定2011年至2012年期间在一家西班牙医院从不同患者中分离出的所有98株MRSA-Tet(R)菌株的spa型和指定的多位点序列分型克隆复合体（CCs），分析其与患者家畜接触情况的可能相关性。所有98株菌株被分为9个CCs：CC398（60.2%）、CC1（19.4%）、CC5（12.2%）和其他CCs（8.2%）。98名患者被分为三组：（A）与家畜有接触（n = 25）；（B）与家畜无接触（n = 42）；（C）无动物接触信息（n = 31）。A组中CC398菌株的比例（76%）显著高于B组（50%）（p < 0.05），C组的比例为61.3%。大多数MRSA-Tet(R)-CC398菌株呈现多重耐药表型，包括对红霉素、克林霉素和环丙沙星耐药，检测到的最常见基因是tet(M)和erm(C)。三株菌株呈现大环内酯类敏感/林可酰胺类耐药表型并含有vga(A)基因。MRSA-CC1菌株对红霉素/克林霉素的耐药百分比（95%/89%）高于MRSA-CC398菌株（58%/63%），且这种耐药通常由erm(C)基因介导。大多数MRSA-CC5菌株对环丙沙星、妥布霉素/卡那霉素和红霉素耐药。所有菌株均未呈现lukF/lukS-PV、tsst-1、eta、etb或etd基因。所有MRSA-CC398菌株均缺乏免疫逃避簇基因，但MRSA-CC1菌株携带这些基因（E型）。总之，尽管在与家畜有接触的患者中检测到MRSA CC398的比例显著更高；但在没有这种接触类型的人群中检测到它也表明其具有人际传播能力。
