RESUMEN
Carbapenem resistance among Klebsiella pneumoniae isolates is often related to carbapenemase genes, located in genetic transmissible elements, particularly the blaKPC gene, which variants are spread in several countries. Recently, reports of K. pneumoniae isolates harboring the blaNDM gene have increased dramatically along with the dissemination of epidemic high-risk clones (HRCs). In the present study, we report the multiclonal spread of New Delhi metallo-beta-lactamase (NDM)-producing K. pneumoniae in different healthcare institutions in the state of Pará, Northern Brazil. A total of 23 NDM-producing isolates were tested regarding antimicrobial susceptibility testing features, screening of carbapenemase genes, and genotyping by multilocus sequencing typing (MLST). All K. pneumoniae isolates were determined as multidrug-resistant (MDR), being mainly resistant to carbapenems, cephalosporins, and fluoroquinolones. The blaNDM-7 (60.9%-14/23) and blaNDM-1 (34.8%-8/23) variants were detected. MLST genotyping revealed the predomination of HRCs, including ST11/CC258, ST340/CC258, ST15/CC15, ST392/CC147, among others. To conclude, the present study reveals the contribution of HRCs and non-HRCs in the spread of NDM-1 and NDM-7-producing K. pneumoniae isolates in Northern (Amazon region) Brazil, along with the first detection of NDM-7 variant in Latin America and Brazil, highlighting the need for surveillance and control of strains that may negatively impact healthcare and antimicrobial resistance.
RESUMEN
OBJECTIVES: To assess the epidemiological features of 76 Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae (KPC-Kp) isolates recovered from three hospitals in Buenos Aires, Argentina, during 2015-2017. METHODS: Antimicrobial susceptibilities were determined according to CLSI Clinical and Laboratoy Standards guidelines. Molecular typing of KPC-Kp was performed by pulsed-field gel electrophoresis (PFGE)-Xbal and multilocus sequence typing. Plasmid encoded genes involved in carbapenem, fosfomycin and colistin resistance were detected by polymerase chain reaction (PCR) and sequencing. Also, mgrB inactivation was investigated in those colistin-resistant isolates. Genetic platforms involved in horizontal spread of blaKPC were investigated by PCR mapping. RESULTS: Besides ß-lactams, high resistance rates were observed for gentamycin, quinolones and trimethoprim-sulfamethoxazole. KPC-Kp sequence type (ST)258 corresponded to 26% of the isolates, while 42% corresponded to ST25. The other isolates were distributed in a diversity of lineages such as ST11 (10.5%), ST392 (10.5%), ST307, ST13, ST101, ST15 and ST551. blaKPC-2 was detected in 75 of 76 isolates, and one ST307 isolate harboured blaKPC-3. Tn4401 was identified as the genetic platform for blaKPC in epidemic lineages such as ST258 and ST307. However, in ST25 and ST392, which are usually not related to blaKPC, a blaKPC-bearing non-Tn4401 element was identified. Alterations in mgrB were detected in seven of 11 colistin-resistant isolates. CONCLUSIONS: Despite previous reports in Argentina, ST258 is no longer the absolute clone among KPC-Kp isolates. In the present study, dissemination of more virulent lineages such as the hypermucoviscous ST25 was detected. The emergence of the high-risk clone ST307 and occurrence of blaKPC-3 was noticed for the first time in this region.