Widespread dispersion of the resistance element tet (B)::IS CR2 in XDR Acinetobacter baumannii isolates

VILACOBA, E.; ALMUZARA, M.; GULONE, L.; TRAGLIA, G. M.; MONTAÑA, S.; RODRÍGUEZ, H.; PASTERAN, F.; PENNINI, M.; SUCARI, A.; GÓMEZ, N.; FERNÁNDEZ, A.; CENTRÓN, D.; RAMÍREZ, M. S.

EPIDEMIOLOGY AND INFECTION.

CAMBRIDGE UNIV PRESS

Año: 2015 vol. 144 p. 1574 - 1578

0950-2688

Acinetobacter baumannii is a significant nosocomial pathogen often associated with extremedrug resistance (XDR). In Argentina, isolates of A. baumannii resistant to tetracyclines haveaccounted for more than 40% of drug-resistant isolates in some hospitals. We have previouslyreported the dispersion of the tet(B) resistance element associated with the ISCR2 transposase inepidemiologically unrelated A. baumannii isolates recovered from 1983 to 2011. This studyextends this surveillance to 77 recent (2009?2013) XDR A. baumannii isolates with different levelsof minocycline susceptibility. Isolates were examined by a pan-PCR assay, which showed sixdifferent amplification patterns, and specific PCRs were used for the confirmation of the theΔISCR2-tet(B)-tet(R)-ISCR2 element. The tet(B) gene was present in 66 isolates and the ISCR2element in 68 isolates; the tet(B) gene was associated with ISCR2 in all tet(B)-positive isolates.We conclude that this element is widespread in XDR A. baumannii isolates from Argentina andcould be responsible for the emergence of tetracycline resistance in recent years.