Randomized trial of biofilm testing to select antibiotics for cystic fibrosis airway infection. Combination antibiotic susceptibility testing to treat exacerbations of cystic fibrosis associated with multiresistant bacteria: a randomised, double-blind, controlled clinical trial. N-acetylcysteine in cystic fibrosis and Pseudomonas aeruginosa infection: clinical score, spirometry and ciliary motility. Inhaled antibiotic therapy in non-cystic fibrosis patients with bronchiectasis and chronic bronchial infection by Pseudomonas aeruginosa. Placebo-controlled, double-blind, randomized study of aerosolized tobramycin for early treatment of Pseudomonas aeruginosa colonization in cystic fibrosis. Elective versus symptomatic antibiotic treatment in cystic fibrosis patients with chronic Pseudomonas infection of the lungs. Chronic Pseudomonas aeruginosa lung infection in cystic fibrosis. A longitudinal study of immune complex activity and inflammatory response in sputum sol-phase of cystic fibrosis patients with chronic Pseudomonas aeruginosa lung infections: influence of local steroid treatment. Antibiotic prophylaxis in cystic fibrosis: inhaled cephaloridine as an adjunct to oral cloxacillin. A formulation of aerosolized tobramycin (Bramitob) in the treatment of patients with cystic fibrosis and Pseudomonas aeruginosa infection: a double-blind, placebo-controlled, multicenter study.
In cystic fibrosis (CF), conventional antibiotic susceptibility results correlate poorly with clinical outcomes. We hypothesized that biofilm testing would more accurately reflect the susceptibilities of bacteria infecting CF airways.
                A multicenter randomized pilot trial was conducted to assess the efficacy and safety of using biofilm susceptibility testing of Pseudomonas aeruginosa sputum isolates to guide antibiotic regimens for chronic airway infections in clinically stable adolescent and adult CF patients. Thirty-nine participants were randomized to biofilm or conventional treatment groups; 14-day courses of two antibiotics were selected according to an activity-based algorithm using the corresponding susceptibility results.
                Of the agents tested, meropenem was most active against biofilm-grown bacteria, and was included in regimens for about half of each study group. For 19 of 39 randomized participants, randomization to the other study group would not have changed the antibiotic classes of the assigned regimen. Study groups were comparable at baseline, and had similar mean decreases in bacterial density, measured in log(10) colony forming units per gram of sputum (biofilm, -2.94 [SD 2.83] vs. conventional, -3.27 [SD 3.09]), and mean increases in forced expiratory volume in 1 sec, measured in liters (0.18 [SD 0.20] vs. 0.12 [SD 0.22]).
                In this pilot study, antibiotic regimens based on biofilm testing did not differ significantly from regimens based on conventional testing in terms of microbiological and clinical responses. The predictive value of biofilm testing may nonetheless warrant evaluation in an adequately powered clinical trial in younger CF patients or those experiencing acute pulmonary exacerbation.
                Copyright © 2011 Wiley-Liss, Inc. We did a randomised, double-blind, controlled clinical trial to prospectively assess whether use of combination antibiotic susceptibility testing improved clinical outcomes in patients with acute pulmonary exacerbations of cystic fibrosis who were infected with multiresistant bacteria.
                251 patients with cystic fibrosis who were chronically infected with multiresistant gram negative bacteria gave sputum at 3-month intervals for conventional culture and sensitivity tests and for combination antibiotic susceptibility tests using multiple combination bactericidal antibiotic testing (MCBT). Patients who developed an exacerbation of pulmonary disease were randomised to receive a 14-day course of any two blinded intravenous antibiotics chosen on the basis of either results from conventional sputum culture and sensitivity testing or the result of MCBT. The primary outcome was time from randomisation until the patient's next pulmonary exacerbation. Analysis was by intention-to-treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN60187870.
                132 patients had a pulmonary exacerbation and were randomised during the 4.5-year study period. The time to next pulmonary exacerbation was not prolonged in the MCBT-treated group (hazard ratio 0.86 in favour of the conventionally-treated group, 95% CI 0.60-1.23, p=0.40). There was no difference between the groups in treatment failure rate. After 14 days of intravenous antibiotic therapy, changes in lung function, dyspnoea, and sputum bacterial density were similar in both groups.
                Antibiotic therapy directed by combination antibiotic susceptibility testing did not result in better clinical and bacteriological outcomes compared with therapy directed by standard culture and sensitivity techniques. The non-bactericidal effects of antibiotic therapy might play an important part in determining improvement in patients with cystic fibrosis pulmonary exacerbations. The effect of peroral N-acetylcysteine (NAC) in patients with cystic fibrosis (CF) and chronic pulmonary Pseudomonas aeruginosa infection was studied in 52 patients in a double-blind, placebo-controlled, cross-over trial of two, 3 month durations. Active treatment consisted of NAC, 200 mg x 3 daily (patients weighing less than 30 kg) or 400 mg x 2 daily (greater than 30 kg). The effect was evaluated by a subjective clinical score, weight, sputum bacteriology, blood leucocyte count, sedimentation rate, titres of specific antimicrobial antibodies, lung function parameters and measurement of nasal ciliary function in vitro. 31 patients completed the study. No significant differences in lung function or subjective clinical scores were seen between NAC and placebo for the study group as a whole. Patients with peak expiratory flow rate (PEFR) below 70% of predicted normal values showed a satisfactory significant increase in PEFR, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) during NAC treatment. No effect of NAC on ciliary activity was observed. The aim of this study was to investigate the long-term effectiveness and safety of inhaled antibiotic treatment in non-cystic fibrosis patients with bronchiectasis and chronic infection by Pseudomonas aeruginosa, after standard endovenous and oral therapy for long-term control of the infection had failed. After completing a 2-week endovenous antibiotic treatment to stabilize respiratory status, 17 patients were randomly allocated to a 12-month treatment either with inhaled ceftazidime and tobramycin (group A) or a symptomatic treatment (group B). One patient from group A abandoned inhaled treatment because of bronchospasm and another from group B died before the end of the study. The remaining 15 patients, seven from group A and eight from group B, completed the study. Both groups had similar previous characteristics. The number of admissions and days of admission (mean +/- SEM) of group A [0.6 (1.5) and 13.1 (34.8)] were lower than those of group B [2.5 (2.1) and 57.9 (41.8)] (P < 0.05). Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), PAO2 and PACO2 were similar in the two groups at the end of follow-up, showing a comparable decline in these parameters. There were no significant differences either in the use of oral antibiotics or in the frequency of emergence of antibiotic-resistant bacteria between groups. Microbiological studies suggested that several patients had different Pseudomonas aeruginosa strains. None of the patients presented impaired renal or auditory function at the end of the study. This study suggests that long-term inhaled antibiotic therapy may be safe and lessen disease severity in non-cystic fibrosis patients with bronchiectasis and chronic bronchial infection by Pseudomonas aeruginosa which do not respond satisfactorily to antibiotics administered via other routes. In chronic Pseudomonas aeruginosa pulmonary infection of patients with cystic fibrosis (CF), antibiotic therapy generally fails to eradicate the bacterial pathogen. The mucoid bacterial phenotype, high sputum production by the host, and low airway levels of antibiotics seem to be responsible for the observed decrease in antibiotic efficacy. We hypothesized that early antibiotic treatment by inhalation in CF patients may be able to prevent or at least delay airway infection. In a prospective placebo-controlled, double-blind, randomized multicenter study, 22 CF patients received either 80 mg b.i.d. of aerosolized tobramycin or placebo for a period of 12 months shortly after the onset of P. aeruginosa pulmonary colonization. Two patients in the tobramycin and six patients in the placebo group stopped inhalation before the 12 month treatment period. Using life table analysis, the time to conversion from a P. aeruginosa-positive to a P. aeruginosa-negative respiratory culture was significantly shorter in the tobramycin-treated group than in the placebo group (P < 0.05, log rank test). Lung function parameters and markers of inflammation did not change in either group during treatment. The results of this study suggest that early tobramycin inhalation may prevent and/or delay P. aeruginosa pulmonary infection in CF patients. A previous retrospective study suggested that a policy of regular anti-pseudomonal antibiotic treatment improved pulmonary function and increased survival in patients with cystic fibrosis chronically infected with Pseudomonas species. The results of a prospective multicentre study to compare the effects on pulmonary function and mortality of three monthly elective anti-pseudomonal antibiotic treatment with conventional symptomatic treatment are reported.
                Sixty patients with cystic fibrosis, chronically infected with P aeruginosa, were randomised to the two treatment arms (elective or symptomatic) and followed clinically at yearly reviews. The major end points were changes in forced expiratory volume in one second (FEV(1)) and forced vital capacity (FVC). Survival was a secondary end point.
                Patients in the symptomatic group received a mean of three antibiotic treatments each year and those in the elective group received four antibiotic treatments during each year of the study. No significant differences in FEV(1) and FVC were found between the two groups after three years. There was a statistically non-significant higher rate of deaths in the elective group (n = 4), three of which were associated with B cepacia infection, compared with the symptomatic group (n = 0).
                This study did not demonstrate an advantage of a policy of elective antibiotic treatment over symptomatic treatment in patients with cystic fibrosis chronically infected with Pseudomonas species. A double blind controlled trial of Becotide (beclomethasone diproprionate) inhalations was carried out for treating cystic fibrosis patients with chronic P. aeruginosa lung infection to determine its efficacy and safety. The aim of the treatment was to diminish the inflammatory response in the lungs of these patients, a response which is initiated by an allergic type III reaction. Pulmonary inflammation was evaluated by measurements of proteolytic activity, albumin concentration and immune complex activity in the sputum sol-phase before, during, and after the 16 weeks the trial lasted. 26 cystic fibrosis patients participated (13 received Becotide and 13 placebo) and the results showed that local steroids have no effect on the inflammatory response in the lungs of cystic fibrosis patients with chronic P. aeruginosa lung infection. No adverse effects were demonstrated. There was, however, a significant increase in the inflammatory parameters for all 26 cystic fibrosis patients when the trial period was over, compared to the insidious pulmonary destruction which takes place in the lungs of these patients, and it corresponded to a significant decrease (p less than 0.05) in forced vital capacity which took place at the same time. Therefore, chronic P. aeruginosa lung infection in these patients should be treated as efficiently as possible. The effect of prophylactic antibiotics on bacterial colonization of the respiratory tract and on general progression of cystic fibrosis was studied in a two-year prospective study of 47 mildly to moderately affected patients. One group of patients received inhaled cephaloridine and the other received no inhaled antibiotic; both groups received cloxacillin orally. Carriage of Haemophilus influenzae was greater in the group not receiving inhaled antibiotic (55% vs 20%). Rates of carriage of Staphylococcus aureus (23%). Pseudomonas aeruginosa (greater than 90%). Pseudomonas cepacia (45%), and other organisms were similar in both groups. There were no significant differences between the two groups in incidence of respiratory tract infections or hospital admissions, clinical scores, radiologic scores, or rate of change of pulmonary function. Although continuous antistaphylococcal antibiotic prophylaxis may be successful in suppressing colonization with S. aureus, it may also contribute to the high rates of carriage of Ps. aeruginosa and Ps. cepacia observed in patients with cystic fibrosis. Chronic infection with Pseudomonas aeruginosa in patients with cystic fibrosis (CF) causes progressive deterioration in lung function. The purpose of this trial was to assess the efficacy and tolerability of a tobramycin highly concentrated solution for inhalation (TSI) [300mg/4mL; Bramitob when added to other antipseudomonal therapies in CF patients with chronic P. aeruginosa infection.
                In a multinational, double-blind, multicenter study, CF patients with chronic P. aeruginosa infection were randomized to receive nebulized tobramycin or placebo over a 24-week study period in which 4-week treatment periods ('on' cycles) were followed by 4-week periods without treatment ('off' cycles). Forced expiratory volume in 1 second (FEV(1)) percentage of predicted normal was used as the primary efficacy outcome parameter. Forced vital capacity (FVC), forced expiratory flow at 25-75% of FVC (FEF(25)(-)(75%)), P. aeruginosa susceptibility, minimum concentration required to inhibit 90% of strains (MIC(90)), rates of P. aeruginosa-negative culture, P. aeruginosa persistence and superinfection, need for hospitalization and parenteral antipseudomonal antibiotics, loss of school/working days due to the disease, and nutritional status (bodyweight and body mass index) were considered as secondary efficacy outcome parameters. Adverse events reporting, audiometry, and renal function were monitored to evaluate the tolerability and safety of TSI.
                A total of 247 patients were randomized in the study. At endpoint time assessment (week 20), FEV(1) was significantly increased in the tobramycin group and the adjusted mean difference between groups (intention-to-treat population) was statistically significant (p < 0.001). At the same time, clinically relevant improvements in FVC and FEF(25-75%) were detected in the TSI group (p = 0.022 and p = 0.001, respectively). The microbiologic outcomes at the end of the last 'on' cycle period were significantly better in the TSI group than the placebo group (p = 0.024), although there was a concomitant trend toward an increase in the MIC of isolated P. aeruginosa strains. The percentage of patients hospitalized as well as the need for parenteral antipseudomonal antibiotics was significantly lower in the TSI group (p = 0.002 and p = 0.009, respectively). Patients treated with TSI had fewer lost school/working days due to the disease (p < 0.001). A favorable effect of tobramycin in terms of an increase in bodyweight and body mass index was also noted, when compared with placebo, at all time points (p < 0.01 and p < 0.001, respectively). No significant changes in serum creatinine and auditory function were detected. The proportion of patients with drug-related adverse events was 15% in both treatment groups.
                Long-term, intermittent administration of this aerosolized tobramycin formulation (300mg/4mL) in CF patients with P. aeruginosa chronic infection significantly improved pulmonary function and microbiologic outcome, decreased hospitalizations, increased nutritional status, and was well tolerated.
The current evidence is insufficient to recommend choosing antibiotics based on biofilm antimicrobial susceptibility testing rather than conventional antimicrobial susceptibility testing in the treatment of Pseudomonas aeruginosa pulmonary infections in people with cystic fibrosis. Future randomized clinical trials on this topic may shed further light on this question.