A semiquantitative MRI-Score can predict loss of lung function in patients with cystic fibrosis: Preliminary results.

OBJECTIVES: To evaluate the applicability of a semiquantitative MRI scoring system (MR-CF-S) as a prognostic marker for clinical course of cystic fibrosis (CF) lung disease. METHODS: This observational study of a single-centre CF cohort included a group of 61 patients (mean age 12.9 ± 4.7 years) receiving morphological and functional pulmonary MRI, pulmonary function testing (PFT) and follow-up of 2 years. MRI was analysed by three raters using MR-CF-S. The inter-rater agreement, correlation of score categories with forced expiratory volume in 1 s (FEV1) at baseline, and the predictive value of clinical parameters, and score categories was assessed for the whole cohort and a subgroup of 40 patients with moderately impaired lung function. RESULTS: The inter-rater agreement of MR-CF-S was sufficient (mean intraclass correlation coefficient 0.92). MR-CF-S (-0.62; p < 0.05) and most of the categories significantly correlated with FEV1. Differences between patients with relevant loss of FEV1 (>3%/year) and normal course were only significant for MR-CF-S (p < 0.05) but not for clinical parameters. Centrilobular opacity (CO) was the most promising score category for prediction of a decline of FEV1 (area under curve: whole cohort 0.69; subgroup 0.86). CONCLUSIONS: MR-CF-S is promising to predict a loss of lung function. CO seems to be a particular finding in CF patients with an abnormal course. KEY POINTS: • Lung imaging is essential in the diagnostic work-up of CF patients • MRI serves as a powerful, radiation-free modality in paediatric CF patients • Observational single-centre study showed significant correlation of MR-CF score and FEV 1 • MR-CF score is promising in predicting a loss of lung function.

Long-Term Pulmonal Therapy of Cystic Fibrosis-Patients with Amitriptyline.

BACKGROUND/AIMS: Several recent clinical studies revealed an accumulation of ceramide in bronchial epithelial cells of patients with cystic fibrosis (CF). Degradation of ceramide concentrations in lungs of CF patients employing the functional acid sphingomyelinase inhibitor amitriptyline revealed a benefit in lung function, weight and exacerbation rates. METHODS: To test for a beneficial effect of amitriptyline in vivo, we performed two phase II randomised, double-blind, placebo-controlled studies. CF patients were treated with 25 mg amitriptyline twice daily, i.e. a total dose of 50 mg/d. After those two studies part of the patients used amitriptyline in an off-lable-use for routine treatment. These patients were observed after one, two and three years after continuous use of amitriptyline and were matched with those patients who were not treated. These patients were used as a control group. RESULTS: After one year of treatment, forced expiratory volume in 1 sec predicted (FEV1) increased significantly by 7.6±7.0%, p=<0.001, and weight increased by 2.1±2.3kg, p=<0.001 in the amitriptyline population (n=20), whereas FEV1 decreased significantly in the control group by 1.8±3.3%, p=0.010, and weight increased by 1.1±2.7kg, p=0.010 (n=14). After two years of treatment, FEV1 increased significantly by 5.6±10.3%, p=0.009, and weight increased by 3.6±2.9kg, p=<0.001 in the amitriptyline population (n=12). In contrast, FEV1 decreased in the control group by 2.1±3.7%, p=0.051 and weight increased by only 0.4±2.9kg, p=0.31 (n=10). After three years of treatment, FEV1 increased significantly by 7.7±8%, p=0.050, and weight increased by 7.3±3.8kg, p=0.016, in the amitriptyline population (n=5), whereas FEV1 decreased in the control group by 1.0±1.3%, p=0.075 and weight increased by 0.4±1.5kg, p=0.29 (n=5). CONCLUSION: Amitriptyline significantly increases FEV1, reduces ceramide in lung cells and increases weight of CF patients.

Regulatory T-cell impairment in cystic fibrosis patients with chronic pseudomonas infection.

RATIONALE: Patients with cystic fibrosis (CF) lung disease have chronic airway inflammation driven by disrupted balance of T-cell (Th17 and Th2) responses. Regulatory T cells (Tregs) dampen T-cell activation, but their role in CF is incompletely understood. OBJECTIVES: To characterize numbers, function, and clinical impact of Tregs in CF lung disease. METHODS: Tregs were quantified in peripheral blood and airway samples from patients with CF and from lung disease control patients without CF and healthy control subjects. The role of Pseudomonas aeruginosa and CF transmembrane conductance regulator (CFTR) in Treg regulation was analyzed by using in vitro and murine in vivo models. MEASUREMENTS AND MAIN RESULTS: Tregs were decreased in peripheral blood and airways of patients with CF compared with healthy controls or lung disease patients without CF and correlated positively with lung function parameters. Patients with CF with chronic P. aeruginosa infection had lower Tregs compared with patients with CF without P. aeruginosa infection. Genetic knockout, pharmacological inhibition, and P. aeruginosa infection studies showed that both P. aeruginosa and CFTR contributed to Treg dysregulation in CF. Functionally, Tregs from patients with CF or from Cftr(-/-) mice were impaired in suppressing conventional T cells, an effect that was enhanced by P. aeruginosa infection. The loss of Tregs in CF affected memory, but not naive Tregs, and manifested gradually with disease progression. CONCLUSIONS: Patients with CF who have chronic P. aeruginosa infection show an age-dependent, quantitative, and qualitative impairment of Tregs. Modulation of Tregs represents a novel strategy to rebalance T-cell responses, dampen inflammation, and ultimately improve outcomes for patients with infective CF lung disease.

Expression and regulation of interferon-related development regulator-1 in cystic fibrosis neutrophils.

A genome-wide association study identified interferon-related development regulator-1 (IFRD1), a protein expressed by neutrophils, as a key modifier gene in cystic fibrosis (CF) lung disease. Here, we investigated the expression and regulation of IFRD1 in CF neutrophils. IFRD1 expression was quantified in peripheral blood and airway neutrophils from patients with CF, patients with non-CF lung disease, and healthy control subjects. The regulation of IFRD1 expression was analyzed using isolated neutrophils and ex vivo stimulation assays with CF airway fluids. IFRD1 single-nucleotide polymorphisms (SNPs) were analyzed in a CF cohort (n = 572) and correlated with longitudinal lung function and IFRD1 expression. Patients with CF expressed higher protein levels of IFRD1 in peripheral blood neutrophils compared with healthy or non-CF disease control subjects. Within patients with CF, IFRD1 protein expression levels in neutrophils were lower in airway fluids compared with peripheral blood. High IFRD1 expression was positively associated with the production of reactive oxygen species (ROS) in CF neutrophils. In vitro regulation studies showed that CF airway fluid and the CF-characteristic chemokines CXCL8 and CXCL2 down-regulated IFRD1 expression in neutrophils, an effect that was mediated through CXCR2. Genetic analyses showed that three IFRD1 SNPs were associated with longitudinal declines in lung function, and modulated IFRD1 expression. These studies demonstrate that IFRD1 expression is systemically up-regulated in human CF neutrophils, is linked to the production of ROS, and is modulated by chemokines in CF airway fluids, depending on the IFRD1 genotype. Understanding the regulation of IFRD1 may pave the way for novel therapeutic approaches to target neutrophilic inflammation in CF.

Noninvasive cardiac output measurement at rest and during exercise in pediatric patients after interventional or surgical atrial septal defect closure.

In the majority of patients, secundum atrial septal defects (ASDs) are treated interventionally or surgically, before the onset of clinical symptoms, between 3 and 6 years of age. Because right-ventricular dimensions usually normalize after ASD closure, it has been assumed that cardiac function and exercise performance also normalize at long-term follow-up. The aim of our study was to determine cardiac index (CI) at rest and during exercise at medium-term follow-up of children who had undergone surgical or interventional closure of ASD because no such reports have been published thus far. Seventeen patients (age range 8.8-17.3 years) who underwent surgical correction were included together with 17 subjects who received an interventional procedure with Amplatzer and Helex occluders (age range 12.2-17.3 years). The study was performed after a median interval of 8.6 years (range 6.5-11.6) after the procedure. Twelve healthy children of comparable age served as controls. CI measurements were performed based on the inert gas-rebreathing method with the Innocor system. For exercise testing, the standard treadmill protocol of the German Society of Pediatric Cardiology was used. CI, stroke volume (SV), and heart rate (HR) were determined at rest and at two standardized submaximal exercise levels (levels 3 and 6). CI increased in all subjects under exercise conditions. Neither SV nor HR displayed significant differences between the three groups either at rest or under exercise conditions. Although HR increased continuously, no increase of indexed SV occurred beyond level 3. Noninvasive determination of CI at rest and during exercise with the IGR method is feasible in the pediatric age group. At medium-term follow-up, we found no significant differences between patients who underwent surgical or interventional ASD closure compared with normal controls.

Clinical and in vitro effect of dornase alfa in mechanically ventilated pediatric non-cystic fibrosis patients with atelectases.

INTRODUCTION: At present no evidence-based medical treatment for persistent atelectasis in pediatric non-cystic fibrosis (CF) patients is available. METHOD: To evaluate the use of intratracheally instilled recombinant human deoxyribonuclease (rhDNase) in intubated and ventilated pediatric patients, we performed a single-center observational study on 46 pediatric intensive care patients who had received intratracheal DNase. Patients were classified, according to radiologic findings of atelectasis (group 1) or infiltrates. As controls we examined a historical control group of 17 patients with atelectasis after cardiac surgery, who had been treated with NaCl 0.9% and matched for age and diagnosis with 21 patients from group 1 (subgroup 1a). Radiologic improvement and inflammatory markers in both serum and tracheal aspirates were measured. RESULTS: In group 1, 35 patients had 51 atelectases/dystelectases episodes at baseline. 67 % of patients showed radiologic signs of improvement after 24h treatment with rhDNase. In subgroup 1a, 16 patients had complete resolution of atelectases and minimal change in dystelectases after a treatment of 24 hours rhDNase, compared with the control group of 17 patients, who had 7 atelectases and 10 dystelectases at baseline and an improvement in only 1 out of 17 (6 %) patients after 24h. CONCLUSION: Intratracheal instillation of rhDNase is an effective adjunct to conservative therapy of atelectases in children. Further randomized controlled prospective studies are necessary.

DNA quantification and fragmentation in sputum after inhalation of recombinant human deoxyribonuclease.

BACKGROUND: Inhaled rhDNase may improve sputum viscosity and mucociliary clearance by cleavage of extracellular DNA derived for instance from dead leukocytes in purulent, highly viscous patient sputum. METHODS: Here we established a method to quantify rhDNase-mediated DNA fragmentation in sputum using gel electrophoresis. Sputum of Pseudomonas aeruginosa colonized cystic fibrosis (CF) patients with (CF+) or without (CF-) rhDNase treatment or mechanically ventilated non-CF patients receiving rhDNase (non-CF+) or not (non-CF-) was analyzed. DNA measurements from T-lymphocytes served as controls. Absolute DNA content and the relative quantity within eight molecular mass ranges (12000 to 200 bp) was determined by gel electrophoresis and densitometric analysis. RESULTS: Geometric mean sputum DNA concentrations were 0.41 mg/dl for CF- (n=54), 0.78 mg/dl for CF+ (n=60), 0.053 mg/dl for non-CF- (n=41) and 0.049 mg/dl for non-CF+ (n=28). Treatment with rhDNase resulted in fragmentation of DNA that was quantified by separation and densitometric analysis of the DNA on agarose gels. The new analysis method permits analysis of DNA cleavage with high accuracy. CONCLUSION: This new monitoring method facilitates DNA quantification and in vitro monitoring of rhDNase in sputum.

Recombinant human deoxyribonuclease shortens ventilation time in young, mechanically ventilated children.

Recombinant human deoxyribonuclease I (dornase alfa) is currently used as an inhaled mucoactive agent in the treatment of cystic fibrosis. In a randomized, placebo-controlled, double-blind clinical study in 100 infants, we investigated whether the therapeutic use of dornase alfa can be extended to ventilated, fluid-restricted children to reduce reintubation rate, ventilation duration, pediatric intensive care unit (PICU) stay, and ventilation complications. While reintubation rates were similar for dornase alfa 7% vs. placebo 9% (odds ratio, 0.77; confidence interval, 0.11-4.9), the incidence of atelectasis (6 vs. 17, respectively; P-value 0.051), median ventilation time (2.2 vs. 3.4 days, respectively; P-value 0.043), median length of PICU stay (7 vs. 8 days, respectively; P-value 0.051), and mean costs (4,830 vs. 6,320, respectively) were lower in the dornase alfa group. No adverse effects were observed, even in critically ill patients. We found that dornase alfa was beneficial and safe. Our findings also indicate that dornase alfa is possibly of value from the first day of mechanical ventilation onward, particularly when longer ventilation (>3 days) is expected in fluid-restricted children after cardiac surgery.

Microbial colonization and lung function in adolescents with cystic fibrosis.

With intensified antibiotic therapy and longer survival, patients with cystic fibrosis (CF) are colonized with a more complex pattern of bacteria and fungi. However, the clinical relevance of these emerging pathogens for lung function remains poorly defined. The aim of this study was to assess the association of bacterial and fungal colonization patterns with lung function in adolescent patients with CF. Microbial colonization patterns and lung function parameters were assessed in 770 adolescent European (German/Austrian) CF patients in a retrospective study (median follow-up time: 10years). Colonization with Pseudomonas aeruginosa and MRSA were most strongly associated with loss of lung function, while mainly colonization with Haemophilus influenzae was associated with preserved lung function. Aspergillus fumigatus was the only species that was associated with an increased risk for infection with P. aeruginosa. Microbial interaction analysis revealed three distinct microbial clusters within the longitudinal course of CF lung disease. Collectively, this study identified potentially protective and harmful microbial colonization patterns in adolescent CF patients. Further studies in different patient cohorts are required to evaluate these microbial patterns and to assess their clinical relevance.