In vitro activity of plazomicin against quinolone-resistant gram-negative bacteria isolated from catheter-associated urinary tract infections

Abstract

Quinolone resistance among uropathogens is an increasing concern. Plazomicin is a new aminoglycoside that shows promising results against resistant bacteria. However, no study has yet tested its effect specifically on quinolone-resistant organisms. This study aimed to evaluate the in vitro activity of plazomicin and comparator drugs against quinolone-resistant Gram-negative isolates of catheter-associated urinary tract infections (CAUTI). Plazomicin demonstrated high inhibiting activity against Enterobacteriaceae isolates (95.9% at MIC≤ 2 mg/L), with MIC_50/90 was 1/2 mg/L. High MICs values were detected against non-Enterobacteriaceae isolates (MIC_50/90, 4/32 mg/L). Plazomicin had susceptibility rate of 97.2% against Enterobacteriaceae isolates carrying aminoglycosides modifying enzymes (AME) genes, while other aminoglycosides, amikacin and gentamicin showed reduced activity (32.4% and 25.4%, respectively). In conclusion, plazomicin showed potent in vitro activity against quinolone-resistant Enterobacteriaceae causing CAUTI, regardless of the AME pattern.

Keywords:

• plazomicin
• quinolone
• resistance
• CAUTI
• AME genes

Availability of data and material

The datasets used in the present study are available from the corresponding author on reasonable request.

Conflict of interest

The authors declare no conflicts of interest or competing interests.

Funding resources

None.

Author contributions

MMEA and SYM contributed to the study design. SN and MEA collected the samples. MMEA and SYM contributed to laboratory experiments. All authors contributed to the data interpretation. All authors drafted the manuscript. All authors revised and approved the final manuscript.

Additional information

Notes on contributors

Marwa Mohamed Ezzat Abd-Elmonsef

Marwa M. E. Abd-Elmonsef, M.D., Associate professor of medical microbiology and immunology, Faculty of Medicine, Tanta University, Egypt. Research Interests: Infectious diseases, Antimicrobials, Antibiotic Resistance, Nosocomial Infection, Bacteriology, Mycology.

Salah Nagla

Salah Nagla, M.D., Associate professor of urology, Faculty of Medicine, Tanta University, Egypt. Research Interests: Urological Diseases and Surgeries, Urinary Tract Infections.

Mohamed Elsayed Afandy

Mohamed E. Afandy, M.D., Lecturer of anesthesia and surgical intensive care, Faculty of Medicine, Tanta University, Egypt. Research Interests: Pain management, Anesthesia, Sedations, Nosocomial Infection in ICU.

Sara Youssef Maxwell

Sara Y. Maxwell, M.D., Lecturer of medical microbiology and immunology, Faculty of Medicine, Tanta University, Egypt. Research Interests: Antimicrobials, Antibiotic Resistance, Nosocomial Infection, Bacteriology, Mycology, Infectious diseases.