Possible role of integrase gene polymerase chain reaction as an epidemiological marker: study of multidrug-resistant Acinetobacter baumannii isolated from nosocomial infections

Eighty-six strains of Acinetobacter baumannii from India and Nepal were investigated for the presence of integrons in relation to multiple drug resistance by integrase gene polymerase chain reaction (PCR). Integrons were found to be present at a rate of 43.02% (37/86). Integrons were significantly correlated with multidrug resistance to several antibiotics. Class 1 integrons were detected in 81.1% of integron-positive strains, whilst 18.9% were found to be positive for class 2 integrons. The majority of class 2 integrons (71%) were encountered in strains isolated from post-operative wards of both countries. The highest integron carriage in isolates of A. baumannii (63.6%) was observed in 2005. Hence, it is likely that integrons play an important role in antibiotic resistance and possibly indicate epidemic behaviour of A. baumannii. Integrase gene PCR may be used as routine screening and identification for the surveillance of clinical isolates of A. baumannii with epidemic potential.