IBS   24490
INSTITUTO DE BIOLOGIA SUBTROPICAL
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
DETECTION OF METALLO-b-LACTAMASES IN Pseudomonas aeruginosa RECOVERED FROM CYSTIC FIBROSIS PATIENTS
Autor/es:
CASCO, DANIELA; MARTINA, PABLO; PEGELS, EDUARDO; VALDEZ, EUSEBIA; QUIROGA, MARINA
Lugar:
Córdoba
Reunión:
Congreso; XI Congreso Argentino de Microbiología General - SAMIGE 2015; 2015
Institución organizadora:
Sociedad Argentina de Microbiologia General - SAMIGE
Resumen:
Pseudomonas aeruginosa is one of the most important nosocomial pathogens, as well as one of main cause of respiratory chronic infection on patient with cystic fibrosis. Its high level of intrinsic antibiotic resistance, coupled with his extraordinary ability to develop additional resistance by chromosomal mutations make this pathogen one of the most difficult to treat. Faced with b-lactam antibiotics, especially carbapenems, common resistance mechanism is impermeability, and there are other mechanisms of clinical importance as the production of enzymes capable of hydrolyzed, called carbapenemases. These mechanisms often coexist, coupled with the presence of chromosomal b-lactamase AMP-C or the co-existence of these mechanisms, or production enzyme capable of hydrolyze, called carbapenemases.The aim of this study was to evaluate the usefulness of the modified Hodge and EDTA-disk synergy tests for the screening of metallo-b-lactamase-producing strains from to imipenem-resistant clinical isolates of P. aeruginosa recovered from CF sputum of patients with chronic respiratory infections. Thirty-two isolates recovered from the sputum of 32 patients with CF during 2013. Samples wereseeded in chocolate agar, blood agar I was analyzed, agar Mac Conkey agar and mannitol salt, and incubated in stove 35 ± 2 ° C for five days. The isolated microorganisms were typed according to standard biochemical tests. Sensitivity to various b-lactam antibiotics was determined and no b-lactams by diffusion assay solid medium and minimum (CIM) to imipenem inhibitory concentration was determined according to CLSI recommendations.Twenty-one per cent of isolates were resistant to Imipenem. The MIC range of Imipenem for theisolates was between 32 and 256 mg/L. Among a total 8 of imipenem-resistant isolates screened by the modified Hodge test and EDTA-disk synergy, we found similar results. Specific PCR for NDM genes yielded 2 positive isolates. The remaining six isolates had negative results for molecular detection of the carbapenemases tested (VIM, NDM, IMP, KPC and OXA).The detection of MBL and other carbapenemases is of utmost importance in deciding the mostappropriate therapeutic regimen for treatment of the carbapenems resistant nonfermenters. Although the results belong to a small sample of one spotlight and the epidemiological situation is particular to the various institutions of the country, it is important to note the prevalence of MBLs in isolates of P. aeruginosa resistant to carbapenems must be taken into account in establishing the empirical antimicrobial therapy.