College of Nursing of Ribeirao Preto, University of São Paulo, São Paulo, Brazil.
School of Pharmaceutical Sciences of Ribeirao Preto, University of São Paulo, São Paulo, Brazil.
Environ Monit Assess. 2020 May 17;192(6):376. doi: 10.1007/s10661-020-08319-w.
Multidrug resistance mediated by β-lactamase in Gram-negative bacilli is a serious public health problem. Sewers are considered reservoirs of multiresistant bacteria due to presence of antibiotics that select them and favor their dissemination. The present study evaluated the antibiotic resistance profile and β-lactamases production in Gram-negative bacilli isolates from hospital sewage and urban wastewater treatment plants (UWWTP) in Brazil. Bacteria were isolated and identified with biochemical tests. Antibiotic susceptibility testing was performed by the disk-diffusion method and detection of extended-spectrum β-lactamase and carbapenemases by enzymatic inhibitor and conventional PCR. Differences in resistance to amoxicillin clavulanic, aztreonam, cefepime, and cefotaxime were observed in hospital sewage compared with urban sewage (p < 0.05). The multidrug-resistant phenotype was observed in 33.3% of hospital sewage isolates (p = 0.0025). β-lactamases genes were found in 35.6% of isolates, with the most frequent being bla and bla (17.8%), and bla and bla (13.3% and 8.9%, respectively). The data obtained are relevant, since the bacteria detected are on the priority pathogens list from the World Health Organization and hospital sewage could be released untreated into the municipal collection system, which may favor the spread of resistance. Changes in hospital sewage discharge practices, as well as additional technologies regarding effluent disinfection in the UWWTP, can prevent the spread of these bacteria into the environment and negative impact on water resources.
β-内酰胺酶介导的革兰氏阴性杆菌多药耐药是一个严重的公共卫生问题。由于存在选择和促进其传播的抗生素，下水道被认为是多耐药细菌的储存库。本研究评估了巴西医院污水和城市污水处理厂（UWWTP）中革兰氏阴性杆菌分离株的抗生素耐药谱和β-内酰胺酶的产生。通过生化试验对细菌进行分离和鉴定。采用纸片扩散法进行抗生素敏感性试验，通过酶抑制剂和常规 PCR 检测超广谱β-内酰胺酶和碳青霉烯酶。与城市污水相比，医院污水中阿莫西林克拉维酸、氨曲南、头孢吡肟和头孢噻肟的耐药率存在差异（p<0.05）。医院污水分离株中观察到多药耐药表型（p=0.0025）。在 35.6%的分离株中发现了β-内酰胺酶基因，最常见的是 bla 和 bla（17.8%），以及 bla 和 bla（13.3%和 8.9%）。所获得的数据是相关的，因为检测到的细菌在世界卫生组织的优先病原体清单上，并且医院污水可能未经处理就排入城市收集系统，这可能会助长耐药性的传播。改变医院污水排放做法以及城市污水处理厂中关于废水消毒的额外技术，可以防止这些细菌传播到环境中并对水资源造成负面影响。
