Geissler Michael, Schröttner Percy, Oertel Reinhard, Dumke Roger
Institute of Medical Microbiology and Virology, University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany.
Institute for Clinical Chemistry and Laboratory Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, 01307 Dresden, Germany.
Microorganisms. 2024 Jan 12;12(1):149. doi: 10.3390/microorganisms12010149.
Vancomycin-resistant (VR) spp. can be detected in high concentrations in wastewaters and pose a risk to public health. During a one-year study (September 2022-August 2023), 24 h composite raw wastewater samples ( = 192) of a municipal wastewater treatment plant were investigated for cultivable enterococci. After growth on Slanetz-Bartley agar (SBA), a mean concentration of 29,736 ± 9919 cfu/mL was calculated. Using MALDI-TOF MS to characterize randomly picked colonies ( = 576), the most common species were found to be (72.6%), (13.7%), and (8.0%). Parallel incubation of wastewater samples on SBA and VRESelect agar resulted in a mean rate of VR enterococci of 2.0 ± 1.5%. All the tested strains grown on the VRESelect agar ( = 172) were and carried the (54.6%) or gene (45.4%) with limited sequence differences. In susceptibility experiments, these isolates showed a high-level resistance to vancomycin (>256 µg/mL). Concentration of vancomycin was determined in 93.7% of 112 wastewater samples (mean: 123.1 ± 64.0 ng/L) and varied between below 100 ng/L (the detection limit) and 246.6 ng/L. A correlation between the concentration of vancomycin and the rate of VR strains among the total enterococci could not be found. The combination of incubation of samples on SBA and a commercial vancomycin-containing agar applied in clinical microbiology with a multiplex PCR for detection of van genes is an easy-to-use tool to quantify and characterize VR spp. in water samples.
耐万古霉素（VR）肠球菌在废水中可被高浓度检测到，对公众健康构成风险。在一项为期一年的研究（2022年9月至2023年8月）中，对一家城市污水处理厂的24小时混合原废水样本（n = 192）进行了可培养肠球菌的调查。在Slanetz-Bartley琼脂（SBA）上生长后，计算出平均浓度为29,736 ± 9919 cfu/mL。使用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）对随机挑选的菌落（n = 576）进行鉴定，发现最常见的菌种为粪肠球菌（72.6%）、屎肠球菌（13.7%）和鸟肠球菌（8.0%）。废水样本在SBA和VRESelect琼脂上同时培养，结果显示VR肠球菌的平均比例为2.0 ± 1.5%。在VRESelect琼脂上生长的所有测试菌株（n = 172）均为肠球菌，携带vanA（54.6%）或vanB基因（45.4%），序列差异有限。在药敏试验中，这些分离株对万古霉素表现出高水平耐药（>256 µg/mL）。在112份废水样本中的93.7%检测到了万古霉素浓度（平均值：123.1 ± 64.0 ng/L），浓度范围在低于100 ng/L（检测限）至246.6 ng/L之间。未发现万古霉素浓度与总肠球菌中VR菌株比例之间存在相关性。样本在SBA上培养以及在临床微生物学中使用含万古霉素的商业琼脂与用于检测van基因的多重聚合酶链反应（PCR）相结合，是一种用于定量和鉴定水样中VR肠球菌的易用工具。
