Multidrug-resistant gram-negative bacteria are an important issue in intensive care units worldwide. Colistin, one of the earliest polymyxin antibiotics, was once widely used for the treatment of gram-negative bacterial infections. However, its use is now limited due to concerns over nephrotoxicity. The appearance of multidrug-resistant species, including A. baumannii and P. aeruginosa, has led...

While the MerR-like transcriptional regulator BrlR has been demonstrated to contribute to Pseudomonas aeruginosa biofilm tolerance to antimicrobial agents known as multidrug efflux pump substrates, the role of BrlR in resistance to cationic antimicrobial peptides (CAP), which is based on reduced outer membrane susceptibility, is not known. Here, we demonstrate that inactivation of brlR coincide...

BACKGROUND Nosocomial infections due to multi-drug resistant Acinetobacter baumannii are often treated with colistin, but there are few data comparing its safety and efficacy with other antimicrobials. METHODS A retrospective cohort study of patients treated with colistin or tobramycin for A. baumannii infections in intensive care units (ICUs) at Groote Schuur hospital. Colistin was used for ...

Recurrent Gram-negative bacterial infection is a significant cause of death in patients with bronchiectasis and severe chronic obstructive pulmonary disease (COPD). Nebulized colistin in cystic fibrosis has shown maintenance of pulmonary function and improved symptom scores. We prospectively followed 18 patients with chronic bronchial sepsis treated with nebulized colistin 30 mg daily. Mean dec...

OBJECTIVE A rise in infections with multidrug-resistant Pseudomonas aeruginosa (MDR-PA) is a significant contributor to increased morbidity and mortality of patients with hematologic malignancies. The aim of this study was to determine the efficacy and safety of colistin (colistimethate sodium) in the treatment of serious infections caused by MDR-PA in these patients. PATIENTS AND METHODS A m...

Despite the marketing of a series of new antibiotics for antibiotic-resistant gram-positive bacteria, no new agents for multiple-antibiotic-resistant gram-negative infections will be available for quite some time. Clinicians will need to find more effective ways to utilize available agents. Colistin is an older but novel antibiotic that fell into disfavor with clinicians some time ago yet still...

Tolerance towards antibiotics of Pseudomonas aeruginosa biofilms is recognized as a major cause of therapeutic failure of chronic lung infection in cystic fibrosis (CF) patients. This lung infection is characterized by antibiotic-tolerant biofilms in mucus with zones of O2 depletion mainly due to polymorphonuclear leukocytic activity. In contrast to the main types of bactericidal antibiotics, i...

BACKGROUND/PURPOSE Ventilator-associated pneumonia (VAP) due to multidrug-resistant (MDR) Acinetobacter baumannii in critically ill patients presents an emerging challenge to clinicians. Administration of aerosolized colistin as an adjunctive therapy is one therapeutic option mentioned in limited evidence-based studies. This study aimed to evaluate the effectiveness of adjunctive aerosolized co...

Transmissible colistin resistance mediated by the mcr gene has been reported worldwide, but clinical isolates of mcr-negative colistin-resistant Escherichia coli are rarely reported. The aim of this study was to evaluate the mechanism of colistin resistance among mcr-positive and mcr-negative E. coli clinical isolates by performing a molecular epidemiological surveillance. For the first time ev...

An alarming increase in the resistance rates of tigecycline and colistin among carbapenemase-producing Acinetobacter baumannii recovered from a Greek hospital over a 3-year period (2011-2013) was investigated. The antimicrobial resistance profiles and carbapenemase gene content were determined for a collection of colistin- and/or tigecycline-resistant carbapenemase-producing A. baumannii isolat...