Decreased susceptibility to nitroimidazoles among Bacteroides species in Brazil

• Published in: Current microbiology Vol. 52; no. 1; pp. 27 - 32
• Main Authors: B D Vieira, Jessica Manya, Boente, Renata F, Rodrigues Miranda, Karla, Avelar, Kátia E S, M C P Domingues, Regina, Candida de S Ferreira, Maria
• Format: Journal Article
• Language: English
• Published: United States Springer Nature B.V 01-01-2006
• Subjects: Anti-Bacterial Agents - pharmacology; Aquatic environment; Bacteria; Bacteroides; Bacteroides - drug effects; Bacteroides - genetics; Bacteroides - isolation & purification; Bacteroides Infections - microbiology; Base Sequence; Brazil; DNA, Bacterial - genetics; Drug Resistance, Bacterial; Feces - microbiology; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Microbiology; Molecular Sequence Data; Nitroimidazoles - pharmacology; Polymerase Chain Reaction; Sequence Alignment; Brazil
• ISSN: 0343-8651; 1432-0991
• DOI: 10.1007/s00284-005-0068-0

In this study, 197 strains of Bacteroides genus from different species and origins were evaluated with regard to their susceptibility to 5-nitroimidazoles (5-Ni)-such as tinidazole, ornidazole, and metronidazole-using the agar dilution method. The presence of nim genes was also investigated by polymerase chain reaction. It was found that 5.6% of Bacteroides strains among all origins showed decreased susceptibility (minimum inhibitory concentrations varying from 4 to 16 microg/ml) to at least one of the imidazoles studied without any known nim gene associate. Also, we detected one strain isolated from a polluted aquatic environment in which one nim gene was found and characterized as nim B using restriction fragment length polymorphism and sequencing. Hence, resistance to 5-Ni should be monitored closely because they constitute, among few drugs, the ones quite effective in treating Bacteroides infections.