A randomized double blind, placebo controlled phase 2 trial of BIIL 284 BS (an LTB4 receptor antagonist) for the treatment of lung disease in children and adults with cystic fibrosis.

BACKGROUND: Airway inflammation, mediated in part by LTB4, contributes to lung destruction in patients with cystic fibrosis (CF). LTB(4)-receptor inhibition may reduce airway inflammation. We report the results of a randomized, double-blind, placebo-controlled study of the efficacy and safety of the leukotriene B(4) (LTB(4))-receptor antagonist BIIL 284 BS in CF patients. METHODS: CF patients aged ≥6 years with mild to moderate lung disease were randomized to oral BIIL 284 BS or placebo once daily for 24 weeks. Co-primary endpoints were change in FEV(1) and incidence of pulmonary exacerbation. RESULTS: After 420 (155 children, 265 adults) of the planned 600 patients were randomized, the trial was terminated after a planned interim analysis revealed a significant increase in pulmonary related serious adverse events (SAEs) in adults receiving BIIL 284 BS. Final analysis revealed SAEs in 36.1% of adults receiving BIIL 284 BS vs. 21.2% receiving placebo (p = 0.007), and in 29.6% of children receiving BIIL 284 BS vs. 22.9% receiving placebo (p = 0.348). In adults, the incidence of protocol-defined pulmonary exacerbation was greater in those receiving BIIL 284 BS than in those receiving placebo (33.1% vs. 18.2% respectively; p = 0.005). In children, the incidence of protocol-defined pulmonary exacerbation was 19.8% in the BIIL 284 BS arm, and 25.7% in the placebo arm (p = 0.38). CONCLUSIONS: While the cause of increased SAEs and exacerbations due to BIIL 284 BS is unknown, the outcome of this trial provides a cautionary tale for the administration of potent anti-inflammatory compounds to individuals with chronic infections, as the potential to significantly suppress the inflammatory response may increase the risk of infection-related adverse events.

Innate immunity in cystic fibrosis lung disease.

Chronic lung disease determines the morbidity and mortality of cystic fibrosis (CF) patients. The pulmonary immune response in CF is characterized by an early and non-resolving activation of the innate immune system, which is dysregulated at several levels. Here we provide a comprehensive overview of innate immunity in CF lung disease, involving (i) epithelial dysfunction, (ii) pathogen sensing, (iii) leukocyte recruitment, (iv) phagocyte impairment, (v) mechanisms linking innate and adaptive immunity and (iv) the potential clinical relevance. Dissecting the complex network of innate immune regulation and associated pro-inflammatory cascades in CF lung disease may pave the way for novel immune-targeted therapies in CF and other chronic infective lung diseases.

Molecular epidemiology of meticillin-resistant Staphylococcus aureus in Italian cystic fibrosis patients: a national overview.

BACKGROUND: The genetic background, transmissibility and virulence of MRSA have been poorly investigated in the cystic fibrosis (CF) population. The aim of this multicentre study was to analyse MRSA strains isolated from CF patients attending nine Italian CF care centres during a two-year period (2004-2005). All CF patients infected by MRSA were included. METHOD: Antibiotic susceptibility testing, SCCmec typing, Panton-Valentine Leukocidin (PVL) production, and Multi Locus Sequence Typing (MLST) analysis were carried out on collected isolates (one strain per patient). RESULTS: One hundred and seventy-eight strains isolated from 2360 patients attending the participating centres were analysed. We detected 56 (31.4%) SCCmec IV PVL-negative strains, with a resistance rate of 80.3% to clindamycin and of 14.5% to trimethoprim/sulphamethoxazole. MLST analysis showed that many isolates belonged to known epidemic lineages. The largest clone grouping of 29 isolates from 6 centres had the genetic background (ST8-MRSA-IV) of the American lineages USA300 and USA500, thus demonstrating the diffusion of these strains in a population considered at risk for hospital associated infections. CONCLUSIONS: Known MRSA epidemic clones such as USA600, USA800, USA1100, and UK EMRSA-3 were described for the first time in Italy. The diffusion of MRSA strains with high pathogenic potential in the CF population suggests that analysis of the MRSA strains involved in pulmonary infections of these patients is needed.

Polymorphonuclear leucocytes consume oxygen in sputum from chronic Pseudomonas aeruginosa pneumonia in cystic fibrosis.

BACKGROUND: Chronic lung infection with Pseudomonas aeruginosa is the most severe complication for patients with cystic fibrosis (CF). This infection is characterised by endobronchial mucoid biofilms surrounded by numerous polymorphonuclear leucocytes (PMNs). The mucoid phenotype offers protection against the PMNs, which are in general assumed to mount an active respiratory burst leading to lung tissue deterioration. An ongoing respiratory burst by the PMNs has, however, not been demonstrated previously in endobronchial secretions from chronically infected patients with CF. OBJECTIVE: Based on the accumulating evidence for depletion of molecular oxygen (O(2)) in the mucus in infected CF bronchi, it was hypothesised that the O(2) depletion in the mucus in infected CF bronchi may be accelerated by the respiratory burst of the PMNs due to the reduction of O(2) to the superoxide anion (O(-)(2)) by the phagocyte NADPH oxidase (Phox). METHODS: Methods were established to isolate the O(2) consumption by the respiratory burst from aerobic respiration in freshly expectorated sputum from chronically infected patients with CF. RESULTS: Inhibition of the Phox with diphenylene iodonium (DPI) delayed O(2) depletion, nearly abolished staining of O(-)(2)-producing PMNs with hydroethidine and inhibited the rapid luminol-enhanced chemiluminescence in sputum. Furthermore, the total O(2) consumption was correlated to the concentration of PMNs in the sputum samples. CONCLUSION: The results demonstrate that CF sputum contains PMNs with an active consumption of O(2) for O(-)(2) production and suggest that the respiratory burst is ongoing and causes accelerated O(2) depletion due to formation of O(-)(2) in the lungs of chronically infected patients with CF.

Resistance to dermcidin-derived peptides is independent of bacterial protease activity.

Dermcidin (DCD) is an antimicrobial peptide constitutively expressed in eccrine sweat glands in human skin. By post-secretory proteolytic processing in sweat, the DCD protein gives rise to anionic and cationic DCD peptides that are able to kill several Gram-positive and Gram-negative bacteria but are only weakly active against Pseudomonas aeruginosa. Here, we questioned whether bacterial resistance to DCD peptides is mediated by proteolytic degradation. It was shown that DCD-derived peptides are degraded by purified bacterial proteases and by extracellular proteases secreted by P. aeruginosa in a concentration-dependent manner. However, protease-deficient mutants of P. aeruginosa PAO1 lacking either lasA, lasB (elastase) or both showed a similar sensitivity towards DCD-derived peptides as the wild-type strain. Finally, inhibition of total protease activity indicated that proteases secreted by P. aeruginosa are not responsible for the poor activity of DCD-derived peptides against P. aeruginosa. These data suggest that the decreased sensitivity of P. aeruginosa to DCD-derived peptides is not mediated by proteolytic degradation under physiological conditions.

Antibiotic-resistant obligate anaerobes during exacerbations of cystic fibrosis patients.

Pseudomonas aeruginosa and Staphylococcus aureus are thought to cause the majority of lung infections in patients with cystic fibrosis (CF). However, other bacterial pathogens may contribute to the pathophysiology of lung disease. Here, obligate anaerobes were identified in a cross-sectional study, and cell numbers and antibiotic susceptibilities of facultative and obligate anaerobes from 114 sputum samples from nine children and 36 adults with CF were determined. Furthermore, in 12 CF patients, we investigated whether conventional intravenous antibiotic therapy, administered during acute exacerbations, would affect the numbers of obligate anaerobes. Fifteen genera of obligate anaerobes were identified in 91% of the CF patients. Cell numbers (mean: 2.2 x 10(7) +/- standard deviation 6.9 x 10(7) CFU/mL of sputum sample) were comparable to those of P. aeruginosa and S. aureus. Staphylococcus saccharolyticus and Peptostreptococcus prevotii were most prevalent. Infection with P. aeruginosa did not increase the likelihood that obligate anaerobes are present in sputum specimens. Single obligate anaerobic species persisted for up to 11 months in sputum plugs in vivo. Patients with and without obligate anaerobes in sputum specimens did not differ in lung function. Intravenous therapy directed against P. aeruginosa during acute exacerbations increased lung function, but did not reduce the numbers of obligate anaerobes. Obligate anaerobic species differed widely in their patterns of resistance against meropenem, piperacillin-tazobactam, clindamycin, metronidazole and ceftazidime. In 58% of patients with acute exacerbations, obligate anaerobes were detected that were resistant to the antibiotics used for treatment. Antibiotic therapy, optimized to target anaerobes in addition to P. aeruginosa, may improve the management of CF lung disease.

[Non-commercial clinical trials--who will be the legal sponsor? Sponsorship of investigator-initiated clinical trials according to the German Drug Law]. / Nichtkommerzielle klinische Prüfung -- wer wird Sponsor? Sponsorverantwortung bei wissenschaftsinitiierten klinischen Prüfungen nach dem deutschen Arzneimittelgesetz.

Non-commercial clinical trials may be of great benefit to the patients concerned. The 12th amendment to the German Drug Law (AMG) changed legal liability of the initiators of investigator-initiated clinical trials with extensive consequences for traditional project leaders. The central point under discussion is the sponsor's responsibility according to the AMG. Presently leading management divisions of university hospitals and universities are developing proceedings to assume sponsor responsibility by institutions (institutional sponsorship), which should enable investigator-initiated clinical trials to be conducted according to legal requirements in the future. Detailed problems and special questions can only be resolved in a single-minded fashion, and if necessary political processes should be catalyzed.

[Drug development in paediatric oncology]. / Arzneimittelentwicklung in der Kinderonkologie.

Cure rates in children with cancer exceed 75 % today. Notwithstanding this high success rate, 60-90 % of drugs employed in Paediatric Oncology are used off label. Comprehensive pre-clinical screening of candidate substances may help to generate entity-specific priority lists and to be faster and more selective in feeding promising candidates into the development process of drugs for use in children. The upcoming EU regulation "Better medicine for children" offers professional societies and their trial groups the opportunity to upgrade existing structures and benefit from the expected increase in paediatric clinical trials. Networking joining more national and international institutions and boards may serve to expand the repertoire of clinical trials and to establish powerful structures. Such a network may be an attractive partner for the drug industry and may thus eventually lead to a reduction in off label use in paediatric oncology.

Early eradication therapy against Pseudomonas aeruginosa in cystic fibrosis patients.

In cystic fibrosis (CF) patients early antibiotic treatment of lung infection has been shown to lead to Pseudomonas aeruginosa eradication. The present study determined: 1) the time period from eradication to new P. aeruginosa acquisition; 2) P. aeruginosa re-growth and new acquisition; and 3) the impact of eradication therapy on lung function, antimicrobial resistance, emergence of other pathogens and treatment costs. Ciprofloxacin and colistin were used to eradicate P. aeruginosa in 47 CF patients. Bacterial pathogens, lung function decline, P. aeruginosa antimicrobial resistance and anti-pseudomonal serum antibodies were assessed quarterly and compared with an age-matched CF control group. Additionally, costs of antibiotic therapy in both groups were assessed. Early antibiotic therapy leads to a P. aeruginosa free-period of a median (range) of 18 (4-80) months. New acquisition with different P. aeruginosa genotypes occurs in 73% of episodes. It also delays the decline of lung function compared with chronically infected patients, prevents the occurrence of antibiotic resistant P. aeruginosa strains, does not lead to emergence of other pathogens, and significantly reduces treatment costs. The treatment substantially lowers P. aeruginosa prevalence in CF. In conclusion, early antibiotic therapy exerts beneficial effects on the patient's clinical status and is cost-effective compared with conventional antibiotic therapy for chronically infected cystic fibrosis patients.

Moxifloxacin and ciprofloxacin protect human respiratory epithelial cells against Streptococcus pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, and Haemophilus influenzae in vitro.

The fluoroquinolones moxifloxacin and ciprofloxacin display excellent in vitro activities against many respiratory tract pathogens. Here we show that moxifloxacin and ciprofloxacin accumulate approximately 7- to 10-fold in primary human respiratory epithelial cells, derived from nasal polyps and grown in 3-dimensional vesicles. Furthermore, using these vesicles, we assessed the bactericidal effect of moxifloxacin on Staphylococcus aureus and Streptococcus pneumoniae and that of ciprofloxacin on Pseudomonas aeruginosa and Haemophilus influenzae. Finally, we determined the protective effect of the fluoroquinolones on vesicles infected with these pathogens. All four bacterial strains were highly toxic for vesicles. S. aureus and S. pneumoniae were readily killed by moxifloxacin regardless whether the antibiotics were present intra/extracellularly or only intracellularly in vesicles. Similar results were obtained for the killing of H. influenzae and P. aeruginosa. Exclusively intracellularly located fluoroquinolones rescued 42% to 76% of the cells after bacterial challenge compared to the rescue of 48% to 94% cells when the fluoroquinolones were present intra/ extracellularly. Without addition of fluoroquinolones cell survival in vesicles was 0% to 38%. The results suggest that intracellular accumulation of moxifloxacin and ciprofloxacin is important for the protection of respiratory epithelial cells from the cytotoxic effects of major respiratory tract pathogens.

Three-dimensional human airway epithelial cell cultures.

An epithelial airway-derived 3-D cell culture model is described. The long lifetime of this model, compared to monolayer cultures of primary cells, allows many experiments with material from one single patient to be performed.

Sequential genotyping of Pseudomonas aeruginosa from upper and lower airways of cystic fibrosis patients.

A controversy exists concerning the adequate specimen to characterise colonisation of cystic fibrosis (CF) airways by Pseudomonas aeruginosa. Oropharyngeal, sputum and bronchoalveolar lavage samples were evaluated from 38 stable CF patients for the detection of P. aeruginosa, genetically different isolates within the same host and longitudinal variations in the genotype during repeated examinations. Bacterial isolates were typed by pulsed-field gel electrophoresis of deoxyribonucleic acid macrorestriction fragments. Sensitivity, negative and positive predictive values and specificity to detect P. aeruginosa were 35.7, 73.5, 83.3 and 96.2% for oropharyngeal cultures in nonexpectorating patients and 91.7, 94.1, 100 and 100% for sputum cultures from expectorating patients, respectively. Genotypes of Pseudomonas isolates recovered from oropharyngeal swabs and sputum differed to the strains recovered by bronchoscopy in 55% and 40%, respectively. In 62% longitudinal variations in the genotype occurred. One-half of these alterations were detectable by bronchoscopy only. In conclusion, sputum samples were of equal value as specimens from bronchoalveolar lavage to detect Pseudomonas aeruginosa colonisation. Cultures from the oropharynx are not suitable for characterising bacterial conditions in the cystic fibrosis lung. Different genotypes within the same host and longitudinal genetic alterations are common and may be detectable in the bronchoalveolar lavage fluid exclusively.

Butane abuse associated Encephalopathy.

Butane contained in household products is easily available for abuse and is not subject to legal prosecution in Germany. The toxicological properties of butane mainly affect the heart and the CNS. A serious pathophysiological mechanism is asphyxia due to the replacement of oxygen by butane. We report an abusive butane inhalation in a 15-year old girl, resulting in cardiopulmonary resuscitation and subsequent development of severe brain damage. After reviewing the medical literature and questioning German toxicological information centres it became obvious, that abuse of butane is an increasing problem. We give an survey about the complications associated with butane intoxication.

Nutrition in patients with cystic fibrosis: a European Consensus.

This document is the result of an European Consensus conference which took place in Artimino, Tuscany, Italy, in March 2001 involving 33 experts on nutrition in patients with cystic fibrosis, organised by the European Cystic Fibrosis Society, and sponsored by Axcan-Scandipharm, Baxter, Dr Falk Pharma, Fresenius, Nutricia, SHS International, Solvay Pharmaceuticals (major sponsor). The purpose of the conference was to develop a consensus document on nutrition in patients with cystic fibrosis based on current evidence.

Effect of inhaled tobramycin on early Pseudomonas aeruginosa colonisation in patients with cystic fibrosis.

Early antibiotic treatment of airway colonisation with Pseudomonas aeruginosa can delay onset of chronic lung infection in patients with cystic fibrosis. Whether the pathogen is eradicated by this treatment is unclear. We successfully eradicated the organism in 14 of 15 patients with cystic fibrosis who had been colonised by P aeruginosa. Patients inhaled 80 mg tobramycin twice daily for 12 months. Eradication was confirmed by sequential respiratory cultures and serum antibody titres that were negative for P aeruginosa. Our antibiotic therapy regimen maintained pulmonary function at high levels.

"Haemoxygenase-1 induction and exhaled markers of oxidative stress in lung diseases", summary of the ERS Research Seminar in Budapest, Hungary, September, 1999.

In recent years, there has been increasing interest in noninvasive monitoring of airway inflammation and oxidative stress. Several volatile and nonvolatile substances can be measured in exhaled breath and have been suggested as potential biomarkers of these events. Exhaled gases, including carbon monoxide (CO), alkanes (ethane, pentane), and substances measured in breath condensate, such as hydrogen peroxide (H2O2) and isoprostanes were all suggested as potential markers of oxidative stress in the lung. A European Respiratory Society (ERS) International Research Seminar entitled "Haemoxygenase-1 induction and exhaled markers of oxidative stress in lung diseases" was organized by the Airway Regulation and Provocation Group of the Clinical Allergy and Immunology Assembly in Budapest, Hungary in September, 1999 to integrate the latest knowledge on these issues and accelerate further improvement in this area. During this 2-day event several issues were raised about: the use and standardization of measurements in exhaled breath; problems of measuring expired H2O2 and other mediators in breath condensate; role and regulation of haemoxygenase (HO)-1 in the lung; and conditions and factors influencing exhaled CO. This report is a summary of the main presentations at the seminar, together with the current areas of research in this rapidly expanding field.

Regulation of Staphylococcus aureus type 5 and type 8 capsular polysaccharides by CO(2).

Staphylococcus aureus expression of capsular polysaccharide type 5 (CP5) has been shown to be downregulated by CO(2). Here we show that CO(2) reduces CP5 expression at the transcriptional level and that CO(2) regulates CP8 expression depending on the genetic background of the strains. Growth in the presence of air supplemented with 5% CO(2) caused a significant decrease in CP8 expression in four S. aureus strains, a marginal effect in four strains, and higher CP8 expression in strain Becker. Absolute CP8 expression in the nine S. aureus strains differed largely from strain to strain. Four groups of strains were established due to sequence variations in the promoter region of cap5 and cap8. To test whether these sequence variations are responsible for the different responses to CO(2), promoter regions from selected strains were fused to the reporter gene xylE in pLC4, and the plasmids were electrotransformed into strains Becker and Newman. XylE activity was negatively regulated by CO(2) in all derivatives of strain Newman and was always positively regulated by CO(2) in all derivatives of strain Becker. Differences in promoter sequences did not influence the pattern of CP8 expression. Therefore, the genetic background of the strains rather than differences in the promoter sequence determines the CO(2) response. trans-acting regulatory molecules may be differentially expressed in strain Becker versus strain Newman. The strain dependency of the CP8 expression established in vitro was also seen in lung tissue sections of patients with cystic fibrosis infected with CP8-positive S. aureus strains.

Anaerobic conditions induce expression of polysaccharide intercellular adhesin in Staphylococcus aureus and Staphylococcus epidermidis.

Products of the intercellular adhesion (ica) operon in Staphylococcus aureus and Staphylococcus epidermidis synthesize a linear beta-1,6-linked glucosaminylglycan. This extracellular polysaccharide mediates bacterial cell-cell adhesion and is required for biofilm formation, which is thought to increase the virulence of both pathogens in association with prosthetic biomedical implants. The environmental signal(s) that triggers ica gene product and polysaccharide expression is unknown. Here we demonstrate that anaerobic in vitro growth conditions lead to increased polysaccharide expression in both S. aureus and S. epidermidis, although the regulation is less stringent in S. epidermidis. Anaerobiosis also dramatically stimulates ica-specific mRNA expression in ica- and polysaccharide-positive strains of both S. aureus and S. epidermidis. These data suggest a mechanism whereby ica gene expression and polysaccharide production may act as a virulence factor in an anaerobic environment in vivo.