Virulence and antimicrobial susceptibility of clinical and environmental strains of Aeromonas spp. from northeastern Brazil

• Published in: Canadian journal of microbiology Vol. 61; no. 8; p. 597
• Main Authors: Castelo-Branco, Débora de Souza Collares Maia, Guedes, Glaucia Morgana de Melo, Brilhante, Raimunda Sâmia Nogueira, Rocha, Marcos Fábio Gadelha, Sidrim, José Júlio Costa, Moreira, José Luciano Bezerra, Cordeiro, Rossana de Aguiar, Sales, Jamille Alencar, Riello, Giovanna Barbosa, de Alencar, Lucas Pereira, Paiva, Manoel de Araújo Neto, Vasconcelos, David Caldas, de Menezes, Isis Sousa Bezerra, de Ponte, Yago Brito, Sampaio, Célia Maria de Souza, Monteiro, André Jalles, Bandeira, Tereza de Jesus Pinheiro Gomes
• Format: Journal Article
• Language: English
• Published: Canada 01-08-2015
• Subjects: Aeromonas - drug effects; Aeromonas - genetics; Aeromonas - pathogenicity; Brazil; Drug Resistance, Bacterial; Environmental Microbiology; Humans; Microbial Sensitivity Tests; Virulence - genetics; Brazil; gènes de virulence; human infections; infections humaines; antimicrobial resistance; environments; Aeromonas spp; environnements; résistance antimicrobienne; virulence genes
• DOI: 10.1139/cjm-2015-0107
• EISSN: 1480-3275

The aims of the present study were to isolate and identify clinical and environmental strains of Aeromonas spp. by means of biochemical tests and the automated method VITEK 2 and to investigate the presence of the virulence genes cytotoxic enterotoxin (act), hemolysin (asa-1), and type III secretion system (ascV), and also the in vitro antimicrobial susceptibility of the strains. From the clinical isolates, 19 Aeromonas hydrophila, 3 Aeromonas veronii bv. sobria, and 1 Aeromonas caviae were identified, while from the environmental strains, 11 A. hydrophila, 22 A. veronii bv. sobria, 1 A. veronii bv. veronii, and 1 A. caviae were recovered. The gene act was detected in 69.5% of clinical isolates, asa-1 in 8.6%, and ascV in 34.7%. In the environmental strains, the detection rates were 51.4%, 45.7%, and 54.2% for the genes act, asa-1, and ascV, respectively. Resistance to amoxicillin-clavulanate and piperacillin-tazobactam was observed in 15 and 3 clinical strains, respectively, and resistance to ceftazidime, meropenem, imipenem, ciprofloxacin, and trimethoprim-sulfamethoxazole was observed in 1 strain for each drug. Resistance to amoxicillin-clavulanate and piperacillin-tazobactam was detected in 17 and 1 environmental strain, respectively. Higher resistance percentages were observed in clinical strains, but environmental strains also showed this phenomenon and presented a higher detection rate of virulence genes. Thus, it is important to monitor the antimicrobial susceptibility and pathogenic potential of the environmental isolates.