Journal Article

Outbreak of OXA-48-producing Enterobacteriaceae in a neonatal intensive care unit in Western Sweden

Hallbäck, Erika Tång, Hentz, Elisabet, Studahl, Marie, Johnning, Anna, Elfvin, Anders, Myhrman, Sofia, Adlerberth, Ingegerd

2023

Overview

In 2015, an outbreak caused by OXA-48-producing Enterobacteriaceae affected a neonatal intensive care unit at a Swedish University Hospital. The aim was to explore the transmission of OXA-48-producing strains between infants and the transfer of resistance plasmids between strains during the outbreak. Twenty-four outbreak isolates from ten suspected cases were whole-genome sequenced. A complete assembly was created for the index isolate ( Enterobacter cloacae ) and used as a mapping reference to detect its plasmids in the remaining isolates (17 Klebsiella pneumoniae , 4 Klebsiella aerogenes , and 2 Escherichia coli ). Strain typing was performed using core genome MLST and SNP analysis. As judged from sequencing and clinical epidemiological data, the outbreak involved nine cases (two developed sepsis) and four OXA-48-producing strains: E. cloacae ST1584 (index case), K. pneumoniae ST25 (eight cases), K. aerogenes ST93 (two cases), and E. coli ST453 (2 cases). Two plasmids from the index strain, p Ecl A2 and p Ecl A4, carrying bla OXA48 and bla CMY-4 , respectively, were traced to all K. pneumoniae ST25 isolates. Klebsiella aerogenes ST93 and E. coli ST453 harboured either only p Ecl A2, or both p Ecl A2 and p Ecl A4. One suspected case harbouring OXA-162-producing K. pneumoniae ST37 could be excluded from the outbreak. Once initiated by an E. cloacae strain, the outbreak was caused by the dissemination of a K. pneumoniae ST25 strain and involved inter-species horizontal transfer of two resistance plasmids, one of which carried bla OXA-48 . To our knowledge, this is the first description of an outbreak of OXA-48-producing Enterobacteriaceae in a neonatal setting in northern Europe.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V
• Subject: Aerogenes / Annan klinisk medicin / Antibiotic resistance / beta-Lactamases - genetics / Biomedical and Life Sciences / Biomedicine / Clinical Medicine / Disease Outbreaks / E coli / Enterobacter cloacae / Enterobacter cloacae - genetics / Enterobacteriaceae / Epidemiology / Escherichia coli / Escherichia coli - genetics / Gene mapping / Genomes / Horizontal transfer / Humans / Infant / Infant, Newborn / Intensive care / Intensive Care Units, Neonatal / Internal Medicine / Klebsiella / Klebsiella aerogenes / Klebsiella Infections - epidemiology / Klebsiella Infections - microbiology / Klebsiella pneumoniae / Klebsiella pneumoniae - genetics / Klinisk medicin / Medical Microbiology / Multilocus Sequence Typing / Neonatal intensive care / Neonates / New-born infant / Original / Original Article / Other Clinical Medicine / Outbreak / Outbreaks / OXA-48 / Plasmid transmission / Plasmids / Plasmids - genetics / Sepsis / Sweden - epidemiology / Whole genome sequencing