Caracterização fenotípica e similiaridade genética de Pseudomonas aeruginosa provenientes de efluentes hospitalares e água superficial do igarapé do Mindu/Manaus - AM

Abstract

Pseudomonas aeruginosa is a leading bacterial cause of nosocomial infections. Possessing aquatic habitats, it presents a good indicator of water contamination. To verify that this bacterial species represents a potential source of contamination to the Mindu stream, we must carry out and analyze the following objectives: first, identify isolates of P. aeruginosa in samples of hospital effluent surface water obtained from the Mindu stream and second, to check whether the strains posses virulence factors as related mobility scourge, "twitching motility", biofilm formation and antimicrobial resistance, and finnaly, to assess the genetic similarity between isolates. Method: To identify the microbiological and biochemical composition, the 16S rRNA gene sequencing was used. For phenotype characterization we performed the following tests: first, we tested for mobility, using the scourge test "twithing motility", second we tested the biofilm formation and profile of antimicrobial resistance using the disk diffusion technique, the genetic similarity among isolates found was determined by PFGE. Results: We identified 17 isolates of P. aeruginosa in effluent water from the hospital. 8 isolates of the same species were in the surface water of the Mindu stream. The strains tested with mobility scourge; 100 % of the strains were found in water Mindu and 88 % of the strains were found in the hospital´s effluent samples were positive for " twitching motility ". All of the 25 isolates studied showed biofilm formation and more than 70 % of the strains found in hospital´s effluent water (raw and treated) had the phenotype of multidrug resistance.100 % of P. aeruginosa isolates found showed resistance to Ampicillin and 50 % of the strains were intermediately resistant to ceftriaxone. Among all the samples, there was genetic similarity; in the hospital´s effluent water and the hospital´s treated sewage, samples found in different seasonal periods, and among isolates found in hospital effluent and surface water of Mindu. Conclusion: The presence of P. aeruginosa containing virulence factors in surface water samples is indicative of the spread of nosocomial origin of microorganisms in the aquatic environment studied. There is strong evidence that the system of sewage treatment in the study is not efficient. Contaminants from P. aeruginosa containing multidrug resistance were in the samples of treated effluent water, and showed high genetic similarity among isolates of P. aeruginosa derived from raw wastewater. Therefore, it is necessary for action and more oversight on the part of health surveillance agencies with health services so that they meet the requirements of the laws in force in order to preserve the environment and people's health.