***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objectives : To evaluate the efficacy and safety of a therapeutic bacteriophage preparation ( Biophage‐PA ) targeting antibiotic‐resistant Pseudomonas aeruginosa in chronic otitis Objectives This study aims to analyze the mortality and the length of ICU stay ( LOS ) of A. baumannii VAP compared to respiratory colonization in patients with mechanical ventilation ( MV ) . Methods A prospect i ve cohort study was performed in an ICU of adult patients ( February 2010–June 2011 ) . One hundred patients on MV with A. baumannii in lower respiratory airways were recruited , and classified as VAP or airways colonization according to CPIS criteria , with a punctuation ≥6 . LOS , 30-days mortality , A. baumannii bacteremia , and clinical features including antibiotic therapy were recorded . Multivariate analysis ( linear and Cox regression ) and survival analysis ( Kaplan-Meier curves ) were performed . Results Fifty-seven VAP and 43 colonized A. baumannii patients were analyzed . Among the A. baumannii strains , 99 % were non-susceptible to carbapenems and the MIC90 of colistin was 0.12 mg/l . Therapy was appropriate in 94.6 % of VAP patients , most of them with colistin 6 MIU/day , although in 13 ( 23.6 % ) cases colistin was started 48 hours after the onset of VAP . Mortality was similar in both groups ( VAP 24.6 % vs. colonized 27.9 % , p = 0.7 ) . Bacteremia and acute kidney insufficiency were associated with decreased survival ( p = 0.02 and p = 0.04 , respectively ) in VAP patients . LOS was 21.5 ( 11.5–42.75 ) vs. 9 ( 6–22 ) days for VAP and colonized patients ( p = 0.004 ) . VAP ( p = 0.003 ) and age ( p = 0.01 ) were independently related to a longer LOS . Conclusions Multidrug-resistant A. baumannii VAP treated with colistin does not have a different mortality compared to lower airways colonization , among patients on mechanical-ventilation , in a setting of high susceptibility to colistin of A. baumannii INTRODUCTION The increased incidence of nosocomial infections by multi-drug resistant Acinetobacter baumannii creates dem and on the application of some combinations of older antimicrobials on that species . We conducted the present observational study to evaluate the efficacy of intravenous and aerosolized colistin combined with rifampicin in the treatment of critically patients with nosocomial infections caused by multiresistant A. baumannii . PATIENTS AND METHODS Critically ill patients with nosocomial infections caused by A. baumannii resistant to all antibiotics except colistin in a medical intensive care unit . Diagnosis of infection was based on clinical data and isolation of bacteria . The bacterial susceptibilities to colistin were tested . Clinical response to colistin+rifampicin was evaluated . RESULTS Twenty-six patients ( 43.58+/-18.29 years , Acute Physiology and Chronic Health Evaluation II Score ( APACHE II ) : 6.35+/-2.99 ) , of whom 16 cases of nosocomial pneumonia treated by aerosolized colistin ( 1x10(6 ) IU three times/day ) associated with intravenous rifampicin ( 10 mg/kg every 12h ) , nine cases of bacteraemia treated by intravenous colistin ( 2x10(6)IU three times/day ) associated with intravenous rifampicin ( 10 mg/kg every 12h ) in which three cases associated with ventilator associated pneumonia and one case of nosocomial meningitis treated by intrathecal use of colistin associated with intravenous rifampicin . The clinical evolution was favourable for all ill patients . Concerning side effects , we have noticed a moderate hepatic cytolysis in three patients . CONCLUSION This is the first clinical report of colistin combined with rifampicin for treatment of A. baumannii infection . Despite the lack of a control group and the limited number of patients , the results seem to be encouraging BACKGROUND Carbapenems are frequently the last line of defence in serious infections due to multidrug-resistant Gram-negative bacteria , but their use is threatened by the growing prevalence of carbapenemase-producing pathogens . Ceftazidime-avibactam is a potential new agent for use in such infections . We aim ed to assess the efficacy , safety , and tolerability of ceftazidime-avibactam compared with best available therapy in patients with complicated urinary tract infection or complicated intra-abdominal infection due to ceftazidime-resistant Gram-negative pathogens . METHODS REPRISE was a pathogen-directed , international , r and omised , open-label , phase 3 trial that recruited patients from hospitals across 16 countries worldwide . Eligible patients were aged 18 - 90 years with complicated urinary tract infection or complicated intra-abdominal infection caused by ceftazidime-resistant Enterobacteriaceae or Pseudomonas aeruginosa . Patients were r and omised ( 1:1 ) to 5 - 21 days of treatment with either ceftazidime-avibactam ( a combination of 2000 mg ceftazidime plus 500 mg avibactam , administered via a 2-h intravenous infusion every 8 h ) or best available therapy . The primary endpoint was clinical response at the test-of-cure visit , 7 - 10 days after last infusion of study therapy , analysed in all patients who had at least one ceftazidime-resistant Gram-negative pathogen , as confirmed by the central laboratory , and who received at least one dose of study drug . Safety endpoints were assessed in all patients who received at least one dose of study drug . This study is registered with Clinical Trials.gov , number NCT01644643 . FINDINGS Between Jan 7 , 2013 , and Aug 29 , 2014 , 333 patients were r and omly assigned , 165 to ceftazidime-avibactam and 168 to best available therapy . Of these , 154 assigned to ceftazidime-avibactam ( 144 with complicated urinary tract infection and ten with complicated intra-abdominal infection ) and 148 assigned to best available therapy ( 137 with complicated urinary tract infection and 11 with complicated intra-abdominal infection ) were analysed for the primary outcome . 163 ( 97 % ) of 168 patients in the best available therapy group received a carbapenem , 161 ( 96 % ) as monotherapy . The overall proportions of patients with a clinical cure at the test-of-cure visit were similar with ceftazidime-avibactam ( 140 [ 91 % ; 95 % CI 85·6 - 94·7 ] of 154 patients ) and best available therapy ( 135 [ 91 % ; 85·9 - 95·0 ] of 148 patients ) . 51 ( 31 % ) of 164 patients in the ceftazidime-avibactam group and 66 ( 39 % ) of 168 in the best available therapy group had an adverse event , most of which were mild or moderate in intensity . Gastrointestinal disorders were the most frequently reported treatment-emergent adverse events with both ceftazidime-avibactam ( 21 [ 13 % ] of 164 patients ) and best available therapy ( 30 [ 18 % ] of 168 patients ) . No new safety concerns were identified for ceftazidime-avibactam . INTERPRETATION These results provide evidence of the efficacy of ceftazidime-avibactam as a potential alternative to carbapenems in patients with ceftazidime-resistant Enterobacteriaceae and P aeruginosa . FUNDING AstraZeneca ABSTRACT We tested 76 extensively drug-resistant ( XDR ) Acinetobacter baumannii isolates by the checkerboard method using only wells containing serum-achievable concentrations ( SACs ) of drugs . Checkerboard results were correlated by time-kill assay and clinical outcomes .  Minocycline-colistin was the best combination in vitro , as it inhibited growth in one or more SAC wells in all isolates . Patients who received a combination that inhibited growth in one or more SAC wells demonstrated better microbiological clearance than those who did not ( 88 % versus 30 % ; P = 0.025 ) . The checkerboard platform may have clinical utility for XDR A. baumannii infections OBJECTIVE The present study examined the effect of high-dose cefoperazone-sulbactam combined with tigecycline against ventilator-associated pneumonia ( VAP ) caused by extensively drug-resistant Acinetobacter baumannii(XDR-AB ) . MATERIAL S AND METHODS 42 patients with VAP due to XDR-AB infection were r and omized into two groups : the TIG group ( received tigecycline injection ) and the TIG+CFS group ( received tigecycline and cefoperazone-sulbactam ( 1 : 1 ) injection ) . Pulsed field gel electrophoresis ( PFGE ) was used for genotyping the isolated XDR-AB . The microdilution method was used to test the minimum inhibitory concentration ( MIC ) of cefoperazone-sulbactam or tigecycline in vitro and the combined effect was determined with the checkerboard method . RESULTS The total combined effectiveness rate ( including all patients who demonstrated an improved condition ) was significantly higher in the TIG+CFS group ( 85.7 % ) compared with the TIG group ( 47.6 % ) ( p = 0.010 ) . No significant differences were noted with regard to the adverse reactions between the two groups . The 42 isolated XDR-AB strains were classified into four types . The MIC of the two drugs in combination was significantly lower than that of each drug used alone ( p < 0.05 ) . CONCLUSION High dose of cefoperazone-sulbactam can improve the antimicrobial activity of tigecycline against XDR-AB . Background Colistin has a narrow therapeutic window with nephrotoxicity being the major dose-limiting adverse effect . Currently , the optimal doses and therapeutic plasma levels are unknown . Methods Prospect i ve observational cohort study , including patients infected by colistin-susceptible P. aeruginosa treated with intravenous colistimethate sodium ( CMS ) .  Clinical data and colistin plasma levels at steady-state ( Css ) were recorded . The primary and secondary end points were clinical cure and 30-day all-cause mortality . Results Ninety-one patients were included .  Clinical cure was observed in 72 ( 79 % ) patients . The mean ( SD ) Css was 1.49 ( 1.4 ) mg/L and 2.42 ( 1.5 ) mg/L ( p = 0.01 ) in patients who achieved clinical cure and those who not , respectively . Independent risk factors for clinical failure were male sex ( OR 5.88 ; 95 % CI 1.09–31.63 ) , APACHE II score ( OR 1.15 ; 95 % CI 1.03–1.27 ) and nephrotoxicity at the EOT ( OR 9.13 ; 95 % CI 95 % 2.06–40.5 ) . The 30-day mortality rate was 30.8 % . Risk factors for 30-day mortality included the APACHE II score ( OR 1.98 ; 95 % CI 1–1.20 ) , the McCabe score ( OR 2.49 ; 95 % CI 1.14–5.43 ) and the presence of nephrotoxicity at the end of treatment ( EOT ) ( OR 3.8 ; 95 % CI 1.26–11.47 ) . Conclusion In this series of patients with infections caused by XDR P. aeruginosa infections , Css is not observed to be related to clinical outcome The aim of this study was to compare the responses of colistin treatment alone vs. a combination of colistin and rifampicin in the treatment of  ventilator-associated pneumonia ( VAP ) caused by a carbapenem-resistant A. baumannii strain . Forty-three patients were r and omly assigned to one of two treatment groups . Although clinical ( P = 0·654 ) , laboratory ( P = 0·645 ) , radiological ( P = 0·290 ) and microbiological ( P = 0·597 ) response rates were better in the combination group , these differences were not significant . However , time to microbiological clearance ( 3·1 ± 0·5 days , P = 0·029 ) was significantly shorter in the combination group . The VAP-related mortality rates were 63·6 % ( 14/22 ) and 38·1 % ( 8/21 ) for the colistin and the combination groups ( P = 0·171 ) , respectively . Our results suggest that the combination of colistin with rifampicin may improve clinical and microbiological outcomes of VAP patients 
    Output:
    
The most common treatment option for A. baumannii and P. aeruginosa infections was intravenous colistin , regardless of infection site .
Clinical success and mortality were similar in A. baumannii infections treated with colistin combination therapy vs. colistin monotherapy , whereas heterogeneous results were found with respect to microbiological success .
Monotherapy and colistin combination therapy were used against P. aeruginosa with clinical and microbiological success ( 70–100 % ) depending on the infection site and severity , and the antibiotic used .
Conclusion We did not find robust evidence for antibiotic treatment of any infection with MDR Gram-negative bacteria , including ESBL-producing Enterobacteriaceae , A. baumannii , and P. aeruginosa , that would lead to a firm recommendation for one specific antibiotic over another or for monotherapy over combination therapy .