Lozano Carmen, González-Barrio David, García Jesús T, Ceballos Sara, Olea Pedro P, Ruiz-Fons Francisco, Torres Carmen
Área Bioquímica y Biología Molecular, Universidad de La Rioja, Logroño, Spain.
Health & Biotechnology (SaBio) Group, Spanish Wildlife Research Institute IREC (CSIC-UCLM-JCCM), Ciudad Real, Spain.
Vet Microbiol. 2015 May 15;177(1-2):168-74. doi: 10.1016/j.vetmic.2015.02.025. Epub 2015 Mar 4.
The detection of vancomycin-resistant-enterococci (VRE) among wild animals represents a worrisome public health concern. The objectives of the study were to determine the possible presence of VRE in faecal samples of wild small mammals in Spain, to characterize the vancomycin resistance mechanisms and genetic lineages of recovered isolates and to know the diversity of enterococcal species in these animals. A total of 155 faecal samples from small mammals were inoculated in Slanetz-Bartley agar supplemented or not with vancomycin (Van-SB/SB plates). The antimicrobial susceptibility profile to 12 antimicrobials and the presence of 20 antimicrobial resistance genes was analyzed. The structure of Tn1546 and the presence of gelE, cylA, asa, esp and hyl genes was studied. Multilocus-sequence-typing (MLST) technique was also performed. VRE isolates were recovered in Van-SB plates in 11 samples. Two samples contained vanB2-positive E. faecalis isolates of lineage ST6, which showed a multiresistance phenotype and harboured the virulence genes gelE and asa. One sample contained a vancomycin-resistant E. faecium isolate of the new lineage ST915, with the vanA gene included into Tn1546 (truncated with IS1542 and IS1216 elements). The vanB2 and vanA isolates were obtained from Rattus rattus. The remaining eight VRE-positive samples contained species with intrinsic vancomycin-resistance mechanisms: E. casseliflavus (n=5) and E. gallinarum (n=3). One hundred and forty-seven vancomycin-susceptible-enterococcal isolates were obtained in SB plates, and E. faecalis and E. faecium were the most frequent detected species. This is the first report of vanB2-containing enterococci in wild animals.
在野生动物中检测到耐万古霉素肠球菌（VRE）是一个令人担忧的公共卫生问题。本研究的目的是确定西班牙野生小型哺乳动物粪便样本中是否可能存在VRE，对分离出的菌株的万古霉素耐药机制和遗传谱系进行表征，并了解这些动物中肠球菌种类的多样性。将来自小型哺乳动物的总共155份粪便样本接种在补充或未补充万古霉素的Slanetz-Bartley琼脂（Van-SB/SB平板）上。分析了对12种抗菌药物的药敏谱以及20种抗菌耐药基因的存在情况。研究了Tn1546的结构以及gelE、cylA、asa、esp和hyl基因的存在情况。还进行了多位点序列分型（MLST）技术。在11份样本的Van-SB平板中分离出了VRE菌株。两份样本含有ST6谱系的vanB2阳性粪肠球菌分离株，表现出多重耐药表型并携带毒力基因gelE和asa。一份样本含有新谱系ST915的耐万古霉素屎肠球菌分离株，其vanA基因包含在Tn1546中（被IS1542和IS1216元件截断）。vanB2和vanA分离株均从黑家鼠中获得。其余8份VRE阳性样本含有具有固有万古霉素耐药机制的菌种：格氏肠球菌（n = 5）和鹑鸡肠球菌（n = 3）。在SB平板中获得了147株万古霉素敏感肠球菌分离株，粪肠球菌和屎肠球菌是最常检测到的菌种。这是在野生动物中首次报告含有vanB2的肠球菌。
