Piperacillin: evaluation against inpatient and gentamicin-resistant bacteria

Area of Science:

• Microbiology
• Antimicrobial Resistance
• Molecular Biology

Background:

• Piperacillin is a crucial antibiotic for treating Gram-negative bacterial infections.
• Understanding the mechanisms and prevalence of piperacillin resistance is vital for effective clinical management.
• Previous studies indicate varying levels of piperacillin activity against different bacterial groups.

Purpose of the Study:

• To compare piperacillin resistance in inpatient versus outpatient bacterial isolates.
• To investigate the relationship between gentamicin resistance and piperacillin resistance.
• To determine if piperacillin resistance is transferable via conjugation and identify associated resistance patterns.

Main Methods:

• Comparative analysis of piperacillin susceptibility in species-matched inpatient and outpatient bacterial collections.
• Evaluation of piperacillin resistance in gentamicin-resistant versus gentamicin-sensitive Gram-negative bacilli.
• Bacterial conjugation experiments to assess the transferability of piperacillin resistance.

Main Results:

• Inpatient bacterial strains exhibited significantly higher piperacillin resistance compared to outpatient strains.
• Gentamicin-resistant Gram-negative bacilli showed significantly greater piperacillin resistance than their sensitive counterparts.
• Piperacillin resistance was successfully transferred via conjugation from multiple Enterobacteriaceae species to Escherichia coli, often co-transferring resistance to other beta-lactam antibiotics.

Conclusions:

• Piperacillin resistance is prevalent in clinical settings and can be acquired through plasmid-mediated transfer.
• The study highlights the need for ongoing surveillance of piperacillin resistance, particularly in hospital environments.
• Understanding resistance mechanisms is crucial for preserving the efficacy of piperacillin and related antibiotics.