In-house rapid colorimetric method for detection of ceftazidime/avibactam resistance in carbapenem resistant Enterobacterales

Abstract

A rapid colorimetric method, the Andrade screening antimicrobial test, was compared with the E-test method to detect ceftazidime/avibactam (CZA) resistance in carbapenem resistant Enterobacterales clinical isolates. A 106 non-duplicated isolates (86 susceptible and 20 resistant to CZA) were chosen for validation. The sensitivity and specificity were 100%. This method investigates CZA resistance regardless of the resistance mechanism involved. It represents an economical and easy technique that can be applied to routine microbiology laboratories. It allows the detection of CZA resistance at 3 hours of incubation and consequently, the early implementation of accurate therapeutic interventions.

Keywords:

• ASAT test
• ceftazidime/avibactam
• ceftazidime/avibactam-resistance
• rapid test
• categorical agreement

Additional information

Funding

This work was supported by Secretaría de Ciencia y Técnica de la Universidad de Buenos Aires (UBACyT 20020130100167BA) to Ángela Famiglietti.

Notes on contributors

Carla Villarroel Lora

Carla Villarroel Lora, Biochemist specialized in Clinical Microbiology, Pharmacy and Biochemistry Faculty, University of Buenos Aires.

Marcela Nastro

Marcela Nastro, PhD, Microbiologist at Bacteriology Laboratory. Clinical Biochemistry Department at University Hospital Jose de San Martin. Pharmacy and Biochemistry Faculty, University of Buenos Aires, Lecturer of Clinical Mirobiology, UBA.

Carlos Vay

Carlos Vay, PhD, Head of Bacteriology Laboratory, Clinical Biochemistry Department at University Hospital Jose de San Martin. Pharmacy and Biochemistry Faculty, University of Buenos Aires, Professor of Clinical Mirobiology, UBA.

Angela Famiglietti

Angela Famiglietti, PhD, Head of Clinical Biochemistry Department at University Hospital Jose de San Martin, University of Buenos Aires, Pharmacy and Biochemistry Faculty, Professor of Clinical Mirobiology, UBA.

Carlos Hernán Rodríguez

Carlos Hernán Rodriguez, PhD, Head of Antimicrobial Agents Area at Bacteriology Laboratory, Clinical Biochemistry Department at University Hospital Jose de San Martin, Pharmacy and Biochemistry Faculty, University of Buenos Aires, Senior lecturer of Clinical Mirobiology, UBA.