Background. The emergence of multi-drug resistant gram negative organisms has led to the frequent use of colistin, an antibiotic first available for clinical use in 1959 but unpopular due to concerns of renal failure. Recent literature suggests colistin nephrotoxicity may be overestimated. Aggressive, weight based dosing with an initial loading dose is recommended for colistin therapy in our in...

OBJECTIVES To elucidate the pharmacokinetic/pharmacodynamic (PK/PD) index that predicts colistin efficacy against Acinetobacter baumannii in neutropenic murine thigh and lung infection models, and to determine the extent of the emergence of resistance in vivo to colistin. METHODS PK/PD of colistin was studied in thigh and lung infection models against A. baumannii ATCC 19606 and two multidrug...

Colistin penetration into the cerebrospinal fluid (CSF) was studied in five critically ill adult patients receiving colistin methanesulfonate for infections by multiresistant gram-negative bacilli. Colistin concentrations were determined in paired serum and CSF samples, with the latter taken by lumbar puncture, with the exception of one patient with an external ventriculostomy. CSF-to-serum rat...

The susceptibility of colistin-resistant clinical isolates of Klebsiella pneumoniae to ceragenins and antimicrobial peptides (AMPs) suggests that there is little to no cross-resistance between colistin and ceragenins/AMPs and that lipid A modifications are found in bacteria with modest changes in susceptibility to ceragenins and with high levels of resistance to colistin. These results suggest ...

background: multi drug resistant (mdr) pseudomonas and acinetobacter species are defined as resistant to at least three classes of antibiotics. most studies have demonstrated that mdr gram negative infections convey increased mortality and morbidity. case: an 11-year –old girl was admitted to pediatric burns unit with burn injury of approximately 68% total body surface area (tbsa). discussion: ...

In vitro activities of colistin and other drugs were tested against 221 Klebsiella pneumoniae isolates that were collected between 2006 and 2007 in nine tertiary care South Korean hospitals from patients with bacteremia. The clonality of colistin-resistant K. pneumoniae (CRKP) isolates was assessed by multilocus sequence typing (MLST). We found that 15 isolates (6.8%) were resistant to colistin...

We tested the effects of various putative efflux pump inhibitors on colistin resistance in multidrug-resistant Gram-negative bacteria. Addition of 10 mg/liter cyanide 3-chlorophenylhydrazone (CCCP) to the test medium could significantly decrease the MICs of colistin-resistant strains. Time-kill assays showed CCCP could reverse colistin resistance and inhibit the regrowth of the resistant subpop...

We thank Dr Mubareka and Dr Rubinstein for their thoughtful commentary [1] related to our recent publication on aerosolized colistin for the treatment of nosocomial pneumonia due to multidrug-resistant Gram-negative bacteria in patients without cystic fibrosis [2]. We would like to provide some additional clarifications related to the formulation of colistin used in our study because the commen...

Acinetobacter baumannii has emerged as an important opportunistic pathogen due to its ability to acquire resistance to most currently available antibiotics. Colistin is often considered as the last line of therapy for infections caused by multidrug-resistant A. baumannii (MDRAB). However, colistin-resistant A. baumannii strain has recently been reported. To explore how multiple drug-resistant A...

BACKGROUND Inhaled antibiotics are commonly used in the treatment of cystic fibrosis lung disease. A previous study suggested neutrophil elastase activation by colistin in vitro. Here, we investigated direct effects of the commonly used antibiotics colistin and tobramycin on neutrophil elastase activity. METHODS Neutrophil elastase was measured spectrophotometrically. The antibiotics colistin...