The route of antimicrobial resistance from the hospital effluent to the environment: focus on the occurrence of KPC-producing Aeromonas spp. and Enterobacteriaceae in sewage

Abstract

We investigated the antimicrobial resistance profile and the occurrence of Klebsiella pneumoniae carbapenemase (KPC)-producing Gram-negative rods in sewage samples obtained from a Brazilian teaching hospital and from the wastewater treatment plant (WWTP) that receives it for treatment. We identified multidrug-resistant bacteria as well as KPC-2-producing Aeromonas spp. and several Enterobacteriaceae species, including Kluyvera spp., in the hospital effluent and in different sites of the WWTP. Most isolates showed the blaKPC-2 gene harbored on a transposon that was carried by conjugative plasmids. The presence of KPC production among Aeromonas spp., Kluyvera spp., and other Enterobacteriaceae indicates the adaptability of such isolates to aquatic environments, not only in the hospital effluent but also throughout the WWTP. Although secondary treatment seems to decrease the amount of KPC producers in sewage, multidrug-resistant isolates are continually disposed in the urban river. Thus, sewage treatment regulations are urgently needed to decelerate the evolution of antimicrobial resistance beyond hospitals.

Detection and Whole-Genome Sequencing of Carbapenemase-Producing Aeromonas hydrophila Isolates from Routine Perirectal Surveillance Culture

“…A eromonas species are Gram-negative environmental bacteria that can cause infections in both immunocompetent and immunocompromised persons (1,2) and have been isolated from a wide range of aquatic environments, including marine ecosystems, freshwater, hospital effluent, and drinking water (1,(3)(4)(5)(6). The global rise of multidrug-resistant bacteria raises concern that a ubiquitous organism, such as an Aeromonas sp., could acquire antibiotic resistance genes derived from human isolates (3,4,7,8).…”

Carbapenem-resistant bacteria in a secondary wastewater treatment plant

“…In the effluent of the secondary municipal wastewater treatment plant, four isolates of CRBP (two members of the family Enterobacteriaceae and two Acinetobacter spp.) were found (Picao et al, 2013). A single isolate of carbapenem-resistant A. baumannii (Girlich et al, 2010) and E. coli (Poirel et al, 2012) were isolated from river water in Europe.…”

“…Therefore, the numbers of viable CRBP in wastewater remain to be determined, in order to quantify the influence of wastewater on the spread of CRBP in the environment. Moreover, the temperature at which the CRBP 35-37°C (Girlich et al, 2010;Ferreira et al, 2011;Walsh et al, 2011;Galler et al, 2014;Tanner et al, 2015) or was not specified at all (Chagas et al, 2011;Poirel et al, 2012;Picao et al, 2013;Zhang et al, 2013). Cultivation at 37°C allows for the isolation of intrinsically carbapenem-resistant bacteria which are autochthonous populations in environmental samples.…”

Pesquisa de genes de resistência a antimicrobianos em filés de tilápia comercializados no município de São Paulo-SP

“…A rápida disseminação entre diferentes espécies bacterianas gram-negativas se deve, provavelmente, à localização dos genes bla KPC em plasmídeos transmissíveis e sua associação a transposons (NAAS et al, 2008;SAMUELSEN et al, 2009;WALSH, 2010;PICÃO et al, 2013 …”

“…As ESBL são codificadas por genes que podem estar localizados em plasmídeos e desta forma, o resultado da circulação do gene bla SHV-28 em peixes de cultivo serve de alerta para disseminação da resistência no ambiente aquático. (GALES et al, 2012;PICÃO et al, 2013 Outras pesquisas têm descrito a presença do gene bla KPC-2 em amostras clínicas de Klebsiella pneumoniae e em outras bactérias gram-negativas, inclusive em Aeromonas spp., que são comuns no ambiente aquático (ANDRADE et al, 2011;SEKI et al, 2011;ALMEIDA et al, 2013;PEREIRA et al, 2013;PICÃO et al, 2013 BALASSIANO et al, 2007;GAO et al, 2012). O gênero Bacillus, por exemplo, é comumente encontrado na aquicultura, pois é amplamente utilizado como probiótico, inclusive na tilapicultura (MELLO, 2012).…”