Reduced Susceptibility to Extended-Spectrum β-Lactams inVibrio choleraeIsolated in Bangladesh.
β-lactams are antibiotic molecules able to inhibit cell wall biosynthesis. Among other mechanisms, resistance in Gram-negative bacteria is mostly associated with production of β-lactamase enzymes able to bind and hydrolyze the β-lactam ring. Extended-spectrum β-lactamases extend this ability also to third- and fourth-generation cephalosporins, as well as to carbapenems and monobactams.Vibrio choleraeis the causative agent of epidemic cholera and a public health burden for developing countries like Bangladesh. Although appropriate oral or intravenous rehydration is the therapy of choice for cholera, severe infections andV. cholerae-associated septicemia are treated with antimicrobial drugs, including doxycycline, erythromycin, azithromycin, ciprofloxacin, and/or third-generation cephalosporins. In the years after the introduction of antibiotics in clinical practice,V. choleraedeveloped resistance to commonly used drugs worldwide mostly through gene acquisitionviahorizontal gene transfer. Reduced susceptibility ofV. choleraeto third-generation cephalosporins has been occasionally documented. However, carbapenemase-producingV. choleraehas been reported at higher rates than resistance to extended-spectrum β-lactams, mainly associated withblaNDM-1emergence and successful plasmid dissemination. Recent findings suggest limited β-lactam resistance is present inV. choleraeO1 isolates collected during ecological and epidemiological surveillance in Bangladesh. However, a trend to intermediate-susceptibility insurgence was observed. Horizontal gene transfer of β-lactam resistance from enteric pathogens to environmental microorganisms should not be underrated, given the ability ofV. choleraeto acquire new genetic information.
Maryland Pathogen Research Institute, University of Maryland , College Park, MD , USA.
Daniela
D
Ceccarelli
International Center for Diarrheal Disease Research, Bangladesh (icddr,b) , Dhaka , Bangladesh.
Munirul
M
Alam
Maryland Pathogen Research Institute, University of Maryland, College Park, MD, USA; Maryland Institute for Applied Environmental Health, University of Maryland, College Park, MD, USA.
Anwar
A
Huq
Maryland Pathogen Research Institute, University of Maryland, College Park, MD, USA; Maryland Institute for Applied Environmental Health, University of Maryland, College Park, MD, USA; Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD, USA; Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
Rita R
RR
Colwell
Bangladesh; Vibrio cholerae; antibiotic resistance; aquatic environment; carbapenems; cholera; clinical environment; extended-spectrum β-lactams