In vitro activity of ceftazidime/avibactam against clinical isolates of ESBL-producing Enterobacteriaceae in Italy

Abstract

Resistance to carbapenems in Enterobacteriaceae is a serious concern for public health. Alternative treatment options involving carbapenem-sparing regimen for patients with serious infections caused by multidrug-resistant Enterobacteriaceae are urgently needed. Ceftazidime/avibactam (CZA) is a new combination of a third generation cephalosporin and a non-β-lactam β-lactamase inhibitor, in which avibactam is capable to expand the ceftazidime activity also against extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. To date, no data exist regarding the activity of CZA against strains isolated in the Italian context, which is known as endemic for ESBL producers. The aim of this study was to evaluate the in vitro activity of CZA, in comparison to ceftazidime (CAZ), against 90 ESBL-producing Escherichia coli and Klebsiella pneumoniae isolates, collected from blood and urine samples at our Institute. Thus, avibactam has been able to restore the activity of CAZ in all cases, suggesting the potential use of CZA as a carbapenem-sparing model, especially when limited therapeutic options exist.

Keywords:

• Ceftazidime/avibactam
• Gram-negative bacteria
• ESBL
• Endemic context
• carbapenem-sparing
• Treatment

Disclosure statement

The authors state that they have no conflicts of interest to declare.

Note on contributors

Valentina Viaggi obtained a degree in Biology at University of Pavia, where she is currently attending the Specialization School in Clinical Microbiology and Virology.

Beatrice Pini obtained a degree in Medicine and Surgery at University of Insubria, Varese. She is a clinical microbiologist in the Clinical Microbiology and Virology Unit, Hospital of Lecco.

Silvia Tonolo obtained a degree in Biology at University of Milan. She is a clinical microbiologist in the Clinical Microbiology and Virology Unit, Hospital of Lecco.

Francesco Luzzaro obtained a degree in Medicine and Surgery at University of Pavia. He is the head of Clinical Microbiology and Virology Unit, Hospital of Lecco. The main research areas of the Unit are bacterial antibiotic resistance mechanisms, with special focus on beta-lactamases. Francesco Luzzaro is also the coordinator of the study group for antibiotics of the Italian Clinical Microbiologists' Association.

Luigi Principe obtained a degree in Biology at University of Rome and a master in Advanced Diagnostic Microbiology at University of Pavia. He is a clinical microbiologist in the Clinical Microbiology and Virology Unit, Hospital of Lecco.