Novel Metallo-β-Lactamase <i>bla</i><sub>CVI-1</sub> Isolated from a <i>Chromobaterium violaceum</i> Clinical Strain Resistant to Colistin
Sonia A. Gomez,
María Belén Sanz,
Melina Rapoport,
Graciela Sucin,
Teresa A. Corallo,
Tomás Poklepovich,
Josefina Campos,
Paola Ceriana,
Juan Manuel de Mendieta,
Mónica Prieto,
Fernando Pasteran,
Alejandra Corso
Affiliations
Sonia A. Gomez
Servicio Antimicrobianos, INEI-ANLIS “Dr. Carlos G. Malbrán”, National and Regional Reference Laboratory in Antimicrobial Resistance (NRRLAR), Buenos Aires C1282AFF, Argentina
María Belén Sanz
Servicio Antimicrobianos, INEI-ANLIS “Dr. Carlos G. Malbrán”, National and Regional Reference Laboratory in Antimicrobial Resistance (NRRLAR), Buenos Aires C1282AFF, Argentina
Melina Rapoport
Servicio Antimicrobianos, INEI-ANLIS “Dr. Carlos G. Malbrán”, National and Regional Reference Laboratory in Antimicrobial Resistance (NRRLAR), Buenos Aires C1282AFF, Argentina
Graciela Sucin
Sector de Bacteriología, Hosp. Pediátrico “Dr. Avelino Castelán”, Resistencia H3508, Argentina
Teresa A. Corallo
Sector de Bacteriología, Hosp. Pediátrico “Dr. Avelino Castelán”, Resistencia H3508, Argentina
Tomás Poklepovich
Plataforma de Genómica y Bioinformática, INEI-ANLIS “Dr. Carlos G. Malbrán”, Buenos Aires CP1281, Argentina
Josefina Campos
Plataforma de Genómica y Bioinformática, INEI-ANLIS “Dr. Carlos G. Malbrán”, Buenos Aires CP1281, Argentina
Paola Ceriana
Servicio Antimicrobianos, INEI-ANLIS “Dr. Carlos G. Malbrán”, National and Regional Reference Laboratory in Antimicrobial Resistance (NRRLAR), Buenos Aires C1282AFF, Argentina
Juan Manuel de Mendieta
Servicio Antimicrobianos, INEI-ANLIS “Dr. Carlos G. Malbrán”, National and Regional Reference Laboratory in Antimicrobial Resistance (NRRLAR), Buenos Aires C1282AFF, Argentina
Mónica Prieto
Servicio Bacteriología Especial INEI-ANLIS "Dr. Carlos G. Malbrán", Buenos Aires CP1281, Argentina
Fernando Pasteran
Servicio Antimicrobianos, INEI-ANLIS “Dr. Carlos G. Malbrán”, National and Regional Reference Laboratory in Antimicrobial Resistance (NRRLAR), Buenos Aires C1282AFF, Argentina
Alejandra Corso
Servicio Antimicrobianos, INEI-ANLIS “Dr. Carlos G. Malbrán”, National and Regional Reference Laboratory in Antimicrobial Resistance (NRRLAR), Buenos Aires C1282AFF, Argentina
Objective: We aimed to describe a colistin (COL)-resistant (R) Chromobacterium violaceum (Cvi) isolate from a septic patient in Argentina expressing a previously unknown gene, blaCVI-1. Methods: In 2019, a 12 year old child was injured with a thorn in a lagoon. The child was hospitalized due to sepsis and multiple abscesses. Cvi was isolated from skin and soft tissue and tracheal aspirate. The patient was successfully treated with imipenem (IMI) plus amikacin. Antimicrobial susceptibility was assessed by disk diffusion, broth microdilution, and the E-test. Carbapenemase activity was assayed by double-disk synergy and microbiological tests. Resistance, virulence, and additional gene searches were performed by in silico analysis of sequences obtained by whole-genome sequencing (WGS). A maximum likelihood phylogenetic tree was built with public Cvi genomes. Results: R was seen for IMI and COL. Expression of a metallo-β-lactamase was confirmed. Genome analysis revealed blaCVI-1, a subclass B2 metallo-β-lactamase with 62.66% ID with CphA from A. hydrophila (WP081086394). R to COL could be attributed to the arnC and arnT genes. Virulence factors required for invasion and toxicity were also found. No plasmids were detected. The phylogeny tree showed two main clades with geographical distinction, and the isolate studied here stands alone in a branch closely related to two clinical isolates from the USA. Conclusions: This is the second report of infection by Cvi in Argentina. This pathogen carried a new gene, blaCVI-1, a metallo-β-lactamase that can be detected by routine methods. Prompt suspicion of C. violaceum infection is crucial to treating this rare pathogen rapidly and properly.