Efficacy and Safety Profile Comparison of Colistin and Tigecycline on the Extensively Drug Resistant <i>Acinetobacter baumannii</i>

Abstract

Colistin and tigecycline are the only therapeutic options for extensively drug resistant Acinetobacter baumannii (XDR-AB), but there is little comparative study. This retrospective observation study evaluated two-colistin and tigecycline-antibiotics profiles like treatment success rate, negative conversion rate, the length of hospital stay, intensive care unit (ICU) stay and antibiotics use, mortality rate during hospital stay and adverse event rate, based on the medical record of XDR-AB positive patients who were treated at least 5 d with those intravenous antibiotics. Treatment success rate of colistin (n 39) and tigecycline (n 16) were not different: 48.7% and 43.8%, respectively (p 0.737), though negative conversion rate was significantly higher in the colistin group: 46.2% against 12.5% (p 0.049). There was no statistically significant difference in mortality rate between two groups during hospital stay (43.6% vs. 56.3%, p 0.393). There were no significant differences in the following parameters: the median length of hospital stay ( The colistin group showed serum creatinine elevation (defined as elevation more than 2.0 mg/dL and 50% increase from the baseline) as 43.6% when compared with 12.5% of the tigecycline group ( p 0.028). As a therapeutic option of XDR-AB, colistin showed significantly better negative conversion rate than tigecycline with more frequent nephrotoxic prevalence, and treatment success rate and mortality rate were not different from both antibiotics groups.

iTRAQ-Based Differential Proteomic Analysis Reveals the Pathways Associated with Tigecycline Resistance in Acinetobacter baumannii

“…Among them, outer membrane proteins are responsible for the influx of drugs in gram-negative pathogen Acinetobacter baumannii. Compared with the standard Acinetobacter baumannii strains, tigecycline-resistant strains show the alteration in outer membrane permeability [19,20]. And this is accompanied by significant changes in the expression of outer membrane proteins in Acinetobacter baumannii strains.…”

Intravenous polymyxins: Revival with puzzle

“…It has been reported that the nephrotoxicity of colistin was not significantly different compared to tobramycin (39), immepenem (32) or ampicillin/sulbactam (42), while the colistin-based treatment had a significantly higher nephrotoxicity than tigecycline-based treatment (36,41).…”

“…Kwon SH et al reported that in A. baumannii infection, microbiologically negative conversion rate was significantly higher in the colistin group than the tigecyclin group, but there was no statistically significant difference in mortality rate between the two groups during hospital stay (36). While another retrospective study, including 294 adults with MDR A. baumannii pneumonia, found an excess mortality of 16.7% in the tigecycline group (41).…”

“…intravenous polymyxins alone in MDR GNB infections, most of which were pneumonias. It's indicated that the mortality ranged from 0% to 74.3% (4,21,(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37), clinical response (cure and improvement) rate 7-82.1%, and microbiological eradication 27.3-73.9% (24,(33)(34)(35)(36)(37)(38). In respect to the colistin only susceptible strains, it's reported that the mortality in hospitals of intravenous colistin monotherapy was 50% (16/32) (Figure 2), 11 patients died in Intensive Care Unit (ICU) (39), and clinical cure was obtained in 82.1% of infectious episodes (23/28) and bacteriological clearance was achieved in 73.9% (17/23) of the cured infectious episodes (38).…”

“…This maybe because these data are generated from a number of small, non-comparative studies or case series, with heterogeneous patient populations, and varying dosing schemes. It's also because different definitions of nephrotoxicity, such as AKIN (Acute Kidney Injury Network) criteria (51,93), RIFLE (33,34,47,53,54), KIDIGO (56), and other criteria (19,36,42). So it's difficult to compare nephrotoxicity between trials.…”