bla(CTX-M-2) and bla(CTX-M-28) extended-spectrum beta-lactamase genes and class 1 integrons in clinical isolates of Klebsiella pneumoniae from Brazil.

Twenty-eight Klebsiella pneumoniae clinical isolates that exhibited an extended-spectrum cephalosporin-resistance profile from a city in the Northeast of Brazil were analysed by PCR and DNA sequencing in order to determine the occurrence of blaCTX-M genes and class 1 integrons. We determined the occurrence of the blaCTX-M-2 gene in six K. pneumoniae isolates and describe the first detection of the blaCTX-M-28 gene in South America.