Resumen

FERNANDEZ COLON, Elena et al. Determining carbapenemases and its relationship to genetic structures in clinical isolates of Acinetobacter baumannii at hospitals in the city of Cochabamba. BIOFARBO [online]. 2009, vol.17, n.1, pp. 30-38. ISSN 1813-5363.

34 clinical isolates of Acinetobacter baumannii were analyzed in this study in order to determine the presence of carbapenemases and its relationship with genetic structures. The samples were collected by staff at the Bolivian-Japanese Gastroenterological Institute at various hospitals in the City of Cochabamba and sent to the Faculty of Biochemistry and Pharmacy. The isolates were taken was from wounds, burns, ulcers and respiratory system. An antibiogram was carried out on isolate using the disk-plate technique to analyze resistance to the groups of antibiotics. A high percent of resistance was observed in most of the isolates and 4 of them were multi-resistant. The detection of carbapenemases was carried out applying phenotypic and genotypic techniques. For the phenotypic detection were used the Hodge test, Hodge with zinc sulfate and DDST (Double Disk Synergy Test) In the Hodge test, there were 25 positive isolates, indicating the presence of carbapenemases. To detect metalobetalactamase, the tests  Hodge with zinc sulfate and DDST were tested, the result was negative for this carbapenemase. The genotypic detection of carbapenemases was carried out through amplification experiments by multiplex PCR to detect Oxacilinasa-type enzymes. Intrinsic OXA-51 carbapenemase of A. baumannii was detected in 33 isolates and OXA-58 carbapenemase in 13 isolates. All the isolates showed bands corresponding to type 1 integrons. The simultaneous presence of 780 pb and 540 pb products was proved.

Palabras llave : A.baumannii; imipenem; carbapenemases; gene OXA-58; integrons.