The growing epidemic of infections in the ICU caused by MDR pathogens has led clinicians to reconsider prescribing pPB and colistin (polymyxin
E) drugs that were removed from use in the past because of their neuro-and nephro-toxicity.17 An earlier study evaluated the efficacy of PB in MDR pathogens when there is very narrow choice.18 In case of A.
B induced nephropathy was defined as the doubling of serum creatinine to a value [greater than or equal to] 2.0 mg/dl (34-35).
Patients who received polymyxin
B treatment were selected from the hospital database and information on basic characteristics, laboratory results, therapeutic options, and outcomes was abstracted.
The commonest pathogen in our study, Pseudomonas aeruginosa, was resistant to the commonly used beta-lactam antibiotics, with more than 66% (30) isolates resistant to all generations of cephalosporin, while 33% isolates being sensitive only to cefipime and 44.4% isolates were sensitive to polymyxins
. All 34 (100%) isolates of S.
While very effective, polymyxins
are relegated to a last-resort option due to the high incidence of kidney toxicity (nephrotoxicity), with rates up to 60% for the polymyxin
coli and also differentiate the chromosome- and plasmid-encoded resistance in 15 minutes, and should be evaluated on other species for which phosphoethanolamine addition is involved in polymyxin
However, 96.5% sensitivity was recorded for polymyxin
B and 97.4% for colistin.
During 2013–2014, polymyxins
B and colistin) exhibited prominent in vitro activity against E.
In vitro pharmacodynamics of polymyxin
B and tigecycline alone and in combination against carbapenem-resistant Acinetobacter baumannii.
Antibacterial action of polymyxin
can be segregated in two parts.
As of July 11, treatment was switched to the triple combination of meropenem (1 g IV TID), tigecycline (50 mg IV BID, after a 100 mg loading dose), and polymyxin
B (500,000 units IV BID).
At this time, CDC recommends that Enterobacteriaceae isolates with a colistin or polymyxin
B MIC >4 ftg/ml be tested for the presence of mcr-1; testing is available through CDC (5).