Characterisation of extended-spectrum β-lactamases among Klebsiella pneumoniae isolates causing bacteraemia and urinary tract infection in Mozambique

The aim of this study was to determine the prevalence of extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae isolated from urinary tract and bloodstream infections in a rural hospital in Manhiça, Mozambique. ESBLs were investigated among ceftriaxone-non-susceptible K. pneumoniae clinical isolates recovered between 2004 and 2009. Characterisation of bla_CTX-M, bla_SHV, bla_OXA and bla_TEM genes was performed by PCR and sequencing. Epidemiological relationships were established by phylogenetic analysis, repetitive extragenic palindromic PCR (REP-PCR), pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), whilst plasmid transferability was evaluated by conjugation. In addition, the presence of class 1 and 2 integrons was studied. A total of 19 K. pneumoniae were analysed. The bla_CTX-M-15 gene was found in all strains. Other ESBL genes were found concomitantly, including bla_SHV-5, bla_SHV-2, bla_SHV-2A, bla_SHV-12 and bla_SHV-38. In addition, other β-lactamases such as bla_TEM-1 and bla_OXA-30 were also detected. REP-PCR identified 15 different epidemiological profiles. MLST analysis also showed great variability of sequence types. The bla_CTX-M-15 gene showed a high transfer capacity. The presence of class 1 integrons was high. High levels of multidrug resistance were also found. In conclusion, these data show the dominance of the CTX-M-type ESBL, particularly CTX-M-15, supporting its worldwide dissemination, including in areas with limited access to third-generation cephalosporins. This finding is a matter of concern for clinical management as third-generation cephalosporins are an alternative for treating severe cases of multidrug-resistant infections in this community.