First Detection in Spain of NDM-1-producing Pseudomonas Aeruginosa in Two Patients Transferred from Ukraine to a University Hospital.

Objectives: Carbapenemase-mediated carbapenem resistance in Pseudomonas aeruginosa is a relevant health problem. We detected for the first time in Spain two clinical NDM-producing P. aeruginosa (NDMPa) isolates in two Ukrainian patients admitted to our hospital between April and August 2022. Methods: Antimicrobial susceptibility was studied by microdilution and MIC gradient strips (EUCAST2022 criteria). Carbapenemase genes were detected by the Xpert Carba-R and immunochromatography assays. WGS (Illumina and Oxford-Nanopore) was also performed. Results: In May 2022, we detected an NDM-Pa in a sternotomy wound in a patient. In June -2022, a second NDM-Pa along with an OXA-48- Klebsiella pneumoniae (OXA-48-Kp) isolate was detected in a mandibular abscess from an unrelated patient. Moreover, an NDM + OXA-48-K. pneumoniae (NDM + OXA48-Kp) was also found in a rectal sample of this patient. Both patients had undergone surgery in Ukraine before their transfer to our hospital. NDM-Pa isolates were resistant to all tested antimicrobials with the exception of aztreonam (MIC = 8 mg/L), colistin (MIC = 2 mg/L) and cefiderocol (MIC range = 0.75-2 mg/L). WGS confirmed that both P. aeruginosa isolates were NDM-1 producers, belonged to ST773 and shared an identical resistome. blaNDM-1 was located on a -117-Kb chromosomally integrated integrative conjugative element (ICE). OXA-48-Kp and NDM + OXA-48-Kp belonged to ST147 and contained blaOXA-48 on an identical -30 0 -Kb IncHIB-plasmid. blaNDM-1 was located on a 51 -Kb IncFIB-plasmid only found in NDM + OXA-48-Kp. Conclusions: This is the first description of NDM-Pa in Spain. We highlight the threat of further crossborder dissemination of NDM-1 through P. aeruginosa along with K. pneumoniae high -risk clones also carrying OXA-48, which draws a complex epidemiological scenario. (c) 2023 The Author(s). Published by Elsevier Ltd on behalf of International Society for Antimicrobial Chemotherapy. This is an open access article under the CC BY -NC -ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )