Polymyxin B and polymyxin E (colistin) are the two polymyxins used in clinical practice. Colistin is a polymyxin-type antibiotic, disrupting the structure of Gram-negative organisms’ cell membranes, rarely used parenterally because it has nephrotoxic side effects. The polymyxins are active against selected Gram-negative bacteria, including Acinetobacter species, Pseudomonas aeruginosa, Klebsiel...

Introduction: Acinetobacter baumannii has been considered a prevalent pathogen in hospitals, raising concern in the medical community due to its broad spectrum of antimicrobial resistance. Since it is a subject that arouses much interest, it has been increasingly studied. Due to the emergence of multidrug-resistant (MDR) Gram-negative bacteria, the use of polymyxins was reestablished. The polym...

Polymyxin B and polymyxin E (colistin) are the two polymyxins used in clinical practice. Colistin is a polymyxin-type antibiotic, disrupting the structure of Gram-negative organisms’ cell membranes, rarely used parenterally because it has nephrotoxic side effects. The polymyxins are active against selected Gram-negative bacteria, including Acinetobacter species, Pseudomonas aeruginosa, Klebsiel...

BACKGROUND The increasing problem of multidrug-resistant gram-negative bacteria causing severe infections and the shortage of new antibiotics to combat them has led to the re-evaluation of polymyxins. These antibiotics were discovered from different species of Bacillus polymyxa in 1947; only two of them, polymyxin B and E (colistin), have been used in clinical practice. Their effectiveness in t...

BACKGROUND There has been an increase in worldwide infections caused by carbapenem-resistant Acinetobacter. This poses a therapeutic challenge as few treatment options are available. OBJECTIVES The aim of this study was to evaluate the efficacy and safety of polymyxins and ampicillin/sulbactam for treating infections caused by carbapenem-resistant Acinetobacter spp. and to evaluate prognostic...

We sought to approach a practical question: Should polymyxins be used in the initial empirical antibiotic regimen in the intensive care unit (ICU) patient with fever that is thought to be due to infection? By retrieving data from the literature and the WHONET Greece, we formulated a mathematical model to estimate the probability (Ptotal) that a gram-negative bacterium susceptible only to polymy...

Polymyxins are polycationic antimicrobial peptides that are currently the last-resort antibiotics for the treatment of multidrug-resistant, Gram-negative bacterial infections. The reintroduction of polymyxins for antimicrobial therapy has been followed by an increase in reports of resistance among Gram-negative bacteria. Some bacteria, such as Klebsiella pneumoniae, Pseudomonas aeruginosa, and ...

Polymyxins are cyclic lipopeptide antibiotics that serve as a last line of defense against Gram-negative bacterial superbugs. However, the extensive accumulation of polymyxins in renal tubular cells can lead to nephrotoxicity, which is the major dose-limiting factor in clinical use. In order to gain further insights into the mechanism of polymyxin-induced nephrotoxicity, we have rationally desi...