Resumo

The spreading of Extended-Spectrum Beta-lactamases (ESBL)-producing bacteria into the community as well as the emergence of carbapenem-resistant pathogens in the environment are a threat to human health and indicate that continuous monitoring systems are required. According, it seems particularly interesting to trace the fate of these bacteria and their genes encoding antibiotic resistance in untreated sewage from hospitals, in sewage after different stages of purification and adjacent environment. In this study, we investigated the ESBL production and the presence of of blaKPC gene in Enterobacteriaceae isolated from non-treated effluent of Hospital Universitário de Londrina, from samples of major municipal wastewater Treatment Plant (WWTP) that receive this hospital sewage and from superficial water of adjacent river where the effluent treated is discharged. The ESBL production was evaluated for 157 Enterobacteriaceae isolates using the Double Disc Sinergy Test and the Combination Disk Method, accordingly the Clinical and Laboratory Standards Institute (CLSI). Fifty two isolates with reduced susceptibility to carbapenems were screened for blaKPC gene as described previously. A total of 79 Enterobacteriaceae (50.3%) isolates resistant to oxyiminocephalosporins were positive in the ESBL- production tests. The 32 (62.5%) of 52 isolates with reduced susceptibility to carbapenems showed the blaKPC gene and presented the Hodge Test positive indicating the carbapenemase production. The ESBL- producing bacteria and the blaKPC gene were detected in all samples investigated, including the hospital and WWTP effluents and river water. This findings poses a serious cause concern witch needs future evaluation and control. Attention should be paid to the horizontal transmission of genes encoding these B-lactamases from hospital to the WWTP and to the surroundings environments.