David Nicolau, PharmD, FCCP, FIDSA
Director
Center for Anti-Infective Research and Development, United States
Disclosure information not submitted.
Title: Beyond the ICU: Assessment of a Global Carbapenem-Resistant P. aeruginosa Cohort from Ward vs ICU
Introduction:
The characteristics of carbapenem-resistant P. aeruginosa (CRPA) globally isolated from ward versus ICU patients are not well described. The present study analyzes the susceptibility profile of CRPA to anti-pseudomonal cephalosporins isolated from ward versus ICU patients globally.
Methods:
CRPA were collected from 2019-2021 during the ERACE-PA global surveillance program (17 sites, 12 countries). Carbapenemase testing was conducted (phenotypic and genotypic). Broth microdilution MICs for ceftazidime (CAZ), cefepime (FEP), ceftolozane/tazobactam (C/T) and ceftazidime/avibactam (CZA) were assessed. The microbiologic characteristics of isolates from patients in the ward or ICU were assessed including percent susceptible per CLSI/EUCAST.
Results:
Of the 807 collected CRPA, 397 were obtained from ward patients versus 275 from ICU (remaining isolates not specified). Respiratory was the most common source in both groups (30% and 55%, respectively) followed by urine in the ward (28%) and blood in the ICU (13%). In each group, 29% and 35% were phenotypically carbapenemase positive, respectively. VIM and GES were the most commonly identified carbapenemase genotype. CZA was the most active agent with 76% and 66% of isolates testing susceptible from each group and MIC50/90 of 4/64 mg/L, respectively. C/T was the second most active with, 65% and 56% of isolates testing susceptible (MIC50/90 1/ >64 and 2/ >64 mg/L, respectively). A similar trend of marginally higher activity in the ward versus ICU isolates was seen for FEP 52%/41% and CAZ 47%/39%, respectively. If carbapenemase-negative, a higher percentage of isolates tested susceptible to C/T and CZA in both groups (ward: 88% and 92%, respectively; ICU: 86% and 89%, respectively).
Conclusion:
In a global collection of CRPA a notable proportion of submitted isolates were obtained from ward patients. FEP and CAZ susceptibility was low for CRPA regardless of isolation in ward or ICU patients. A high proportion remained susceptible to C/T and CZA, particularly in non-carbapenemase harboring isolates. Clinicians should be cognizant of this reduced susceptibility in CRPA regardless of where the patient is located (i.e., ward versus ICU). These data should be considered for empiric therapies in patients with risk factors or colonized with CRPA even from the ward.