CARBAPENEM-SPARING ANTIBIOTIC TREATMENT OPTIONS FOR HOSPITAL-ACQUIRED K. PNEUMONIAE AND P. AERUGINOSA RESPIRATORY-TRACT INFECTIONS FROM MALAYSIA SMART STUDY 2017-2020

Abstract

Intro: This study aims to determine the Gram-negative pathogens distribution in hospital-acquired (HA) (≥48 hours from admission date) respiratory tract infections (RTI) and the antibiotics susceptibility against the common Gramnegative pathogens. We report ceftolozane/tazobactam (C/T) and various antibiotics susceptibility against K. pneumoniae and P. aeruginosa isolated from HA-ICU and non-ICU wards across Malaysia. Methods: Total of 902 Gram-negative-HA-RTI pathogens were collected from 2017-2020 across 5 Malaysia SMART sites. Of which, 517 from non-ICU and 334 from ICU were collected and susceptibility was compared between non-ICU and ICU isolates against top two most prevalent pathogen, K. pneumoniae and P. aeruginosa. MICs were determined using broth microdilution and interpreted with CLSI breakpoints. The Gram-negative pathogens were tested against ceftazidime (CAZ), ceftriaxone (CRO), cefepime (FEP), piperacillin/tazobactam (P/T), ceftolozane/tazobactam (C/T), meropenem (MEM) and imipenem (IMI). Findings: K. pneumoniae and P. aeruginosa continue to be the top two Gram negative pathogens in RTI including those hospital-acquired. In HA-RTI, P. aeruginosa contributed 28% of pathogen distribution in both isolates collected from non-ICU and ICU wards. The distribution of K. pneumoniae markedly decreased in ICU at 29.9% compared to non-ICU at 48.7%. K. pneumoniae showed decreased susceptibility to almost all non-carbapenem antibiotics including CAZ, CRO, FEP, P/T ranging from 63.89% - 80.56% in non-ICU isolates to 51.0% - 65.0% for ICU isolates. C/T maintained susceptibility at 85.71% in non-ICU isolates and 70.0% in ICU isolates. P. aeruginosa similarly showed decreased susceptibility against CAZ, FEP, P/T ranging from 83.45% - 88.97% in non-ICU isolates to 74.74% – 84.21% in ICU isolates, while C/T maintained susceptibility at 96.55% in non-ICU isolates and 94.74% in ICU isolates. Conclusion: Study highlights decreased susceptibility of K. pneumonia and P. aeruginosa in HA-ICU isolates. C/T maintained high susceptibility against both pathogens in ICU and non-ICU and may be considered a carbapenem-sparing option if carbapenem-resistant Acinetobacter is not suspected.