Detecção de genes de resistência aos antibióticos em bactérias isoladas de efluentes hospitalares

Abstract

Antibiotic resistant bacteria (ARB) have emerged and spread among human and animal populations worldwide. Here, we evaluated the presence of ARB and antibiotic resistance genes (ARG) in two hospital effluents located in Brazil. Effluent aliquots were inoculated in a selective medium supplemented with antibiotics. Bacterial identification was performed by MALDI-TOF, and ARG were investigated by PCR. Two hundred eight strains were isolated from two hospital effluents (H1 = 117; H2 = 91). A wide variety of species of Enterobacterales and non- Enterobacterales were isolated, and Enterobacter spp. (13.0%), Proteus mirabilis (10.1%), and Klebsiella pneumoniae (9.6%) were prevalent. blaTEM and blaKPC were more frequent beta-lactamases encoding genes, while the predominant macrolide resistance genes were mph(A) and mel. Many species carried the three tetracycline resistance genes (tetD, tetM, tetA) and strB was prevalent aminoglycoside resistance gene. Two Staphylococcus haemolyticus strains were detected harboring the mecA gene. The researched quinolone, colistin, and vancomycin resistance genes were not found. The findings of our work highlight the importance of hospital effluent as a disseminator of ARB and ARG; strict monitoring and regulations of hospital effluent treatments are needed in order to avoid the spread of these genes among bacteria present in the environment.