The Clinical and Molecular Epidemiology of CTX-M-9 Group Producing Enterobacteriaceae Infections in Children.

Abstract

INTRODUCTION:

The pandemic of extended-spectrum beta-lactamase-(ESBL)-producing Enterobacteriaceae (Ent) is strongly linked to the dissemination of CTX-M-type-ESBL-Ent. We sought to define the epidemiology of infections in children due to an emerging resistance type, CTX-M-9-group-producing-Ent (CTX-M-9-grp-Ent).

METHODS:

A retrospective matched case-control analysis of children with CTX-M-9-grp-Ent infections who received medical care at three Chicago area hospitals was performed. Cases were defined as children possessing extended-spectrum cephalosporin-resistant (ESC-R) infections due to blaCTX-M-9. PCR and DNA analysis assessed beta-lactamase (bla) genes, multi-locus sequence types (MLST) and phylogenetic grouping of E. coli. Controls were children with ESC-susceptible (ESC-S)-Ent infections matched one case to three controls by age, source, and hospital. The clinical-epidemiologic predictors of CTX-M-9-grp-Ent infection were assessed.

RESULTS:

Of 356 ESC-R-Ent isolates from children (median age 4.1 years), the CTX-M-9-group was the solely detected bla gene in 44 (12.4%). The predominant species was E. coli (91%) of virulent phylogroups D (60%) and B2 (40%). MLST revealed multiple strain types. On multivariable analysis, CTX-M-9-grp-Ent occurred more often in E. coli than other Ent genera (OR 7.4, 95% CI 2.4, 27.2), children of non-Black-White-Hispanic race (OR 7.4, 95% CI 2.4, 28.2), and outpatients (OR 4.5, 95% CI 1.7, 12.3), which was a very unexpected finding for infections due to antibiotic-resistant bacteria. Residents of South Chicago had a 6.7 times higher odds of having CTX-M-9-grp-Ent infections than those in the reference region (West), while residence in Northwestern Chicago was associated with an 81% decreased odds of infection. Other demographic, comorbidity, invasive-device, and antibiotic use differences were not found.

CONCLUSION:

CTX-M-9-grp-Ent infection may be associated with patient residence and is occurring in children without traditional in-patient exposure risk factors. This suggests that among children, the community environment may be a key contributor in the spread of these resistant pathogens.

• Authors: Latania K Logan, Rachel L Medernach, T Nicholas Domitrovic, Jared R Rispens, Andrea M Hujer, Nadia K Qureshi, Steven H Marshall, David C Nguyen, Susan D Rudin, Xiaotian Zheng, Sreenivas Konda, Robert A Weinstein, Robert A Bonomo
• Journal: Infectious diseases and therapy (Infect Dis Ther) Vol. 8 Issue 2 Pg. 243-254 (Jun 2019) ISSN: 2193-8229 [Print] New Zealand
• PMID: 30772921 (Publication Type: Journal Article)