Characterization of ESBL-producing Escherichia coli and Klebsiella pneumoniae from bloodstream infections in three hospitals in Bucharest, Romania: a preliminary study.

BACKGROUND

Our objective was to describe the distribution of extended-spectrum beta-lactamase (ESBL) genes found in Escherichia coli and Klebsiella pneumoniae isolates from hospital-acquired or community-onset bloodstream infections (BSIs) in Bucharest, Romania.

METHODS

E. coli and K. pneumoniae isolates, resistant to at least one antimicrobial drug family, were analyzed for genes encoding ESBL by PCR and sequencing. The E. coli isolates were screened by an ST131 clone allele-specific PCR for the pabB gene.

RESULTS

ESBL genes were found in 30 (35%) of 85 drug-resistant E. coli and 19 (70%) of 27 drug-resistant K. pneumoniae. Twenty-nine (97%) E. coli carried blaCTX-M-15. Nineteen (63%) E. coli carrying an ESBL gene belonged to the ST131 clonal group. The blaCTX-M-15 gene was found in 15 (79%) and blaSHV-12 in 12 (63%) K. pneumoniae isolates.

CONCLUSION

In Bucharest CTX-M15 was the most frequently encountered ESBL in both E. coli and K. pneumoniae BSI isolates regardless of the setting of infections.