Sonia Gomez

Clonal dissemination of Klebsiella pneumoniae ST258 harbouring KPC-2 in Argentina

The present work describes the abrupt emergence of Klebsiella pneumoniae carbapenemase (KPC) and characterizes the first 79 KPC-producing enterobacteria from Argentina (isolated from 2006 to 2010). The emergence of bla(KPC-2) was characterized by two patterns of dispersion: the first was the sporadic occurrence in diverse enterobacteria from distant geographical regions, harbouring plasmids of different incompatibility groups and bla(KPC-2) in an unusual genetic environment flanked by ISKpn8-Δbla(TEM-1) and ISKpn6-like. bla(KPC-2) was associated with IncL/M transferable plasmids; the second was the abrupt clonal spread of K. pneumoniae ST258 harbouring bla(KPC-2) in Tn4401a.

Intrapatient emergence of OXA-247: a novel carbapenemase found in a patient previously infected with OXA-163-producing Klebsiella pneumoniae

Two genetically related Klebsiella pneumoniae strains carrying OXA-type carbapenemases were isolated from a single patient 1 month apart. Kpn163 harboured OXA-163 and Kpn247 a new variant named OXA-247 that showed susceptibility to carbapenems and expanded-spectrum cephalosporins similar to OXA-48. Our epidemiological, biochemical and molecular results suggest the intrapatient emergence of blaOXA -247 from blaOXA -163.

Emergence of NDM-1-producing Klebsiella pneumoniae in Guatemala

Servicio Antimicrobianos, Instituto Nacional de Enfermedades Infecciosas (INEI)-ANLIS ‘Dr. Carlos G. Malbran’, Ciudad Autonoma de Buenos Aires, Argentina; Seccion Bacteriologia, UCREVE/ Laboratorio Nacional de Salud, Ciudad de Guatemala, Guatemala; Hospital Infantil de Infectologia y Rehabilitacion, Ciudad de Guatemala, Guatemala; Hospital General San Juan de Dios, Ciudad de Guatemala, Guatemala; Alert and Response and Epidemic Diseases, Pan American Health Organization/World Health Organization, Washington, DC, USA

Evaluation of the Blue-Carba Test for Rapid Detection of Carbapenemases in Gram-Negative Bacilli

The Blue-Carba test (BCT) is a biochemical test for rapid (<2 h) detection of carbapenemase production in Gram-negative bacilli directly from bacterial culture ([1][1]). It is based on the in vitro hydrolysis of imipenem by bacterial colonies (direct inoculation without prior lysis), which is

Detection of an international multiresistant clone belonging to sequence type 654 involved in the dissemination of KPC-producing Pseudomonas aeruginosa in Argentina

Servicio Antimicrobianos, Departamento Bacteriologia, Instituto Nacional de Enfermedades Infecciosas (INEI), ANLIS ‘Dr Carlos G. Malbran’, Ciudad Autonoma de Buenos Aires, Argentina; Bacteriologia, Hospital Zonal de Bariloche ‘Ramon Carillo’, Rio Negro, Argentina; Infectologia, Hospital Privado Regional del Sur, Rio Negro, Argentina; Infectologia, Sanatorio del Sol, Bariloche, Rio Negro, Argentina

Emergence of genetically unrelated NDM-1-producing Acinetobacter pittii strains in Paraguay

Fil: Pasteran, Fernando. Direccion Nacional de Institutos de Investigacion. Administracion Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas. Area de Antimicrobianos; Argentina

qnrE1 , a Member of a New Family of Plasmid-Located Quinolone Resistance Genes, Originated from the Chromosome of Enterobacter Species

ABSTRACT qnrE1, found in a clinical Klebsiella pneumoniae isolate, was undetectable by PCR assays used for the six qnr families. qnrE1 was located on a conjugative plasmid (ca. 185 kb) and differed from qnrB alleles by 25%. Phylogenetic reconstructions of qnr genes and proteins and analysis of the qnrE1 surroundings showed that this gene belongs to a new qnr family and was likely mobilized by ISEcp1 from the chromosome of Enterobacter spp. to plasmids of K. pneumoniae.

Rapid Identification of OXA-48 and OXA-163 Subfamilies in Carbapenem-Resistant Gram-Negative Bacilli with a Novel Immunochromatographic Lateral Flow Assay

ABSTRACT We assessed a novel immunochromatographic lateral flow assay for direct identification of OXA-48-like carbapenemases and accurate differentiation of allele variants with distinct substrate profiles (OXA-48 or OXA-163 subfamilies). The assay allowed rapid (less than 4 min) and reliable direct confirmation of OXA-163- and/or OXA-48-like enzymes (with 100% sensitivity and 100% specificity) from cultured colonies that were recovered from both solid medium and spiked blood culture bottles.

Performance of a PCR assay for the rapid identification of the Klebsiella pneumoniae ST258 epidemic clone in Latin American clinical isolates

The worldwide dissemination of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae ST258 demands a rapid PCR-based typing method to detect unique genes of the ST258 clone. This study evaluates a PCR developed by Adler et al. (2014) for the detection of ST258 in K. pneumoniae clinical isolates centered on the identification of the pilv-I and prp genes. We tested 143 clinical isolates from Argentina (n=109), Chile (n=1), Colombia (n=1), Costa Rica (n=2), Ecuador (n=5), El Salvador (n=2), Nicaragua (n=5), Panamá (n=2), Paraguay (n=2), Perú (n=3) and Trinidad and Tobago (n=11) recovered from 2006 to 2015. blaKPC, pilv-l and prp genes were detected by PCR and sequenced by standard procedures. ST258 and non-ST258 were defined by PFGE and/or MLST. Isolates were grouped according to PFGE patterns: 58 were compatible with ST258 (group 1) and 85 with non-ST258 (group 2). MLST study was done on an arbitrary selection of isolates. The pilv-l gene was present only in ST258 isolates, regardless of the presence of the blaKPC gene. Results for the prp gene were variable. Its presence did not define ST258. The pilv-I PCR had a sensitivity and specificity of 100%, respectively, for the detection of ST258 in the isolates under investigation. Given our findings, the pilv-I PCR could replace more time and resource consuming methods, allowing for more rapid detection of the circulating high risk K. pneumoniae clone ST258 in Latin American (LA) countries.

In vivo horizontal dissemination of the blaKPC-2 gene carried on diverse genetic platforms among clinical isolates of Enterobacteriaceae

This study investigated the molecular characteristics of six blaKPC-positive Enterobacteriaceae recovered from three patients in Argentina. Antimicrobial susceptibility testing was performed following Clinical and Laboratory Standards Institute (CLSI) 2014 recommendations. Molecular characterisation of the isolates was performed by biparental conjugation, PCR, sequencing, S1 nuclease restriction, and Southern blot hybridisation with a blaKPC probe using standard protocols and conditions. The isolates studied were as follows. Case 1: Escherichia coli (ECO-P1) and Klebsiella pneumoniae (KPN-P1) isolated from a rectal swab harboured blaKPC-2 in transposon Tn4401a on non-typeable and non-conjugative plasmids. Case 2: Enterobacter cloacae (ECL-P2) and K. pneumoniae (KPN-P2) were isolated from two blood cultures. blaKPC-2 was found in a novel genetic variant of ISKpn8-blaKPC-2-ISKpn6-like on conjugative plasmids of IncL/M type. Case 3, Citrobacter freundii (CFR-P3) and Klebsiella oxytoca (KOX-P3) were isolated from skin and skin-structure infection. The blaKPC gene was detected on ISKpn8-ΔblaTEM-blaKPC-2-ISKpn6-like located on an IncA/C conjugative plasmid. CFR-P3 and KOX-P3 harboured blaPER-2 in addition to the blaKPC gene. In conclusion, we document the horizontal dissemination of blaKPC-2 from diverse Enterobacteriaceae clinical isolates with different genetic backgrounds. This is the first report of E. coli harbouring blaKPC associated with Tn4401a in Argentina.