DETECÇÃO DE MICRORGANISMOS PRESENTES NO EFLUENTE HOSPITALAR E NA ESTAÇÃO DE TRATAMENTO DE ESGOTO DE GOIÂNIA: PRESENÇA DE BACTÉRIAS GRAM-NEGATIVAS RESISTENTES AOS ANTIMICROBIANOS.

Abstract

Introduction: The emergence of antimicrobial-resistant genes is becoming an increasingly important ecological issue. The selective pressure of antimicrobials is a significant factor in the selection and dissemination of resistance genes in the environment. Objective: The objective of this present study was to detect, isolate and identify Pseudomonas aeruginosa, Acinetobacter spp., Klebsiella pneumoniae and Escherichia coli in the sewage effluents of 10 hospitals located in Goiânia and to assess the susceptibility profile of the isolated microorganisms. Methodology: The samples collected in the hospital effluents and from the Goiânia sewage treatment station were identified using biochemical tests, Gram-staining, microscopy, motility-indole-ornithine (MIO) medium, urea, catalase, oxidase, TAF, API 20E, API STAPH (Bio Merieux) and bile-esculin agar. Following identification, the profile of susceptibility to the antimicrobials was evaluated using the agar diffusion disk susceptibility test, later classified according to the NCCLS (2002). Next, the E. coli strains were analyzed regards the possibility extended spectrum β-lactamase production (ESBL), using phenotypic tests. Results: A total of 73 microorganisms gram-negative were identified including 10 strains of E. coli (14,92 por cent), 10 strains of K. pneumoniae (14,92 por cent), 3 of P. aeruginosa (4.47 ´por cent) and 1 of A. baumannii (1.49 por cent). The E. coli strains presented 100 por cent total resistance to aztreonam, 40 por cent to ampicillin, 30 por cent to piperacillin, 20% to ciprofloxacin and 10 por cent to gentamicin. None of the aztreonam-resistant E. coli strains were identified as being extended spectrum Beta-lactamase producers. P. aeruginosa presented 100 por cent resistance to ampicillin-sulbactam and 100 por cent intermediary resistance to gentamicin. Strains of K. pneumoniae were resistant to ampicillin (70 por cent) and to piperacillin (20 por cent). Additionally, 50 por cent showed intermediate resistance to piperacillin. No cases of total resistance were detected in the sample of A. baumannii, which presented only intermediary resistance to aztreonam and ceftriaxone. Conclusion: The E. coli, P. aeruginosa, K. pneumoniae and A. baumannii isolates showed low resistance rates. None of the bacterial strains produced ESBL or carbapenems. The samples of A. baumannii had the highest susceptibility profile of all the microorganisms isolated.