Carbapenem-resistant Citrobacter spp. isolated in Spain from 2013 to 2015 produced a variety of carbapenemases including VIM-1, OXA-48, KPC-2, NDM-1 and VIM-2

• Published in: Journal of antimicrobial chemotherapy 2017-12, Vol.72 (12), p.3283-3287
• Main Authors: Arana, David M, Ortega, Adriana, González-Barberá, Eva, Lara, Noelia, Bautista, Verónica, Gómez-Ruíz, Dolores, Sáez, David, Fernández-Romero, Sara, Aracil, Belén, Pérez-Vázquez, María, Campos, José, Oteo, Jesús
• Format: Article
• Language: English
• Subjects: Bacterial Proteins - genetics; beta-Lactamases - genetics; Carbapenem-Resistant Enterobacteriaceae - classification; Carbapenem-Resistant Enterobacteriaceae - enzymology; Carbapenem-Resistant Enterobacteriaceae - genetics; Carbapenem-Resistant Enterobacteriaceae - isolation & purification; Citrobacter - classification; Citrobacter - enzymology; Citrobacter - genetics; Citrobacter - isolation & purification; Electrophoresis, Gel, Pulsed-Field; Enterobacteriaceae Infections - epidemiology; Enterobacteriaceae Infections - microbiology; Genetic Variation; Genotype; Humans; Molecular Epidemiology; Molecular Typing; Polymerase Chain Reaction; Sequence Analysis, DNA; Spain - epidemiology
• ISSN: 0305-7453; 1460-2091
• DOI: 10.1093/jac/dkx325

There is little information about carbapenemase-producing (CP) Citrobacter spp. We studied the molecular epidemiology and microbiological features of CP Citrobacter spp. isolates collected in Spain (2013-15). In total, 119 isolates suspected of being CP by the EUCAST screening cut-off values were analysed. Carbapenemases and ESBLs were characterized using PCR and sequencing. The genetic relationship among Citrobacter freundii isolates was studied by PFGE. Of the 119 isolates, 63 (52.9%) produced carbapenemases, of which 37 (58.7%) produced VIM-1, 20 (31.7%) produced OXA-48, 12 (19%) produced KPC-2, 2 (3.2%) produced NDM-1 and 1 (1.6%) produced VIM-2; 9 C. freundii isolates co-produced VIM-1 plus OXA-48. Fourteen isolates (22.2%) also carried ESBLs: 8 CTX-M-9 plus SHV-12, 2 CTX-M-9, 2 SHV-12 and 2 CTX-M-15. Fifty-seven isolates (90.5%) were C. freundii, 4 (6.3%) were Citrobacter koseri, 1 (1.6%) was Citrobacter amalonaticus and 1 (1.6%) was Citrobacter braakii. By EUCAST breakpoints, eight (12.7%) of the CP isolates were susceptible to the four carbapenems tested. In the 53 CP C. freundii analysed by PFGE, a total of 44 different band patterns were observed. Four PFGE clusters were identified: cluster 1 included eight isolates co-producing VIM-1 and OXA-48; blaVIM-1 was carried in a class 1 integron (intI-blaVIM-1-aacA4-dfrB1-aadA1-catB2-qacEΔ1/sul1) and blaOXA-48 was carried in a Tn1999.2 transposon. We observed the clonal and polyclonal spread of CP Citrobacter spp. across several Spanish geographical areas. Four species of Citrobacter spp. produced up to five carbapenemase types, including co-production of VIM-1 plus OXA-48. Some CP Citrobacter spp. isolates were susceptible to the four carbapenems tested, a finding with potential clinical implications.