ECFS standards of care on CFTR-related disorders: Towards a comprehensive program for affected individuals.

After three publications defining an updated guidance on the diagnostic criteria for people with cystic fibrosis transmembrane conductance regulator (CFTR)-related disorders (pwCFTR-RDs), establishing its relationship to CFTR-dysfunction and describing the individual disorders, this fourth and last paper in the series addresses some critical challenges facing health care providers and pwCFTR-RD. Topics included are: 1) benefits and obstacles to collect data from pwCFTR-RD are discussed, together with the opportunity to integrate them into established CF-registries; 2) the potential of infants designated CRMS/CFSPID to develop a CFTR-RD and how to communicate this information; 3) a description of the challenges in genetic counseling, with particular regard to phenotypic variability, unknown long-term evolution, CFTR testing and pregnancy termination 4) a proposal for the assessment of potential barriers to the implementation and dissemination of the produced documents to health care professionals involved in the care of pwCFTR-RD and a process to monitor the implementation of the CFTR-RD recommendations; 5) clinical trials investigating the efficacy of CFTR modulators in CFTR-RD and how endpoints and outcomes might be adapted to the heterogeneity of these disorders.

CXCL10 deficiency limits macrophage infiltration, preserves lung matrix, and enables lung growth in bronchopulmonary dysplasia.

Preterm infants with oxygen supplementation are at high risk for bronchopulmonary dysplasia (BPD), a neonatal chronic lung disease. Inflammation with macrophage activation is central to the pathogenesis of BPD. CXCL10, a chemotactic and pro-inflammatory chemokine, is elevated in the lungs of infants evolving BPD and in hyperoxia-based BPD in mice. Here, we tested if CXCL10 deficiency preserves lung growth after neonatal hyperoxia by preventing macrophage activation. To this end, we exposed Cxcl10 knockout (Cxcl10-/-) and wild-type mice to an experimental model of hyperoxia (85% O2)-induced neonatal lung injury and subsequent regeneration. In addition, cultured primary human macrophages and murine macrophages (J744A.1) were treated with CXCL10 and/or CXCR3 antagonist. Our transcriptomic analysis identified CXCL10 as a central hub in the inflammatory network of neonatal mouse lungs after hyperoxia. Quantitative histomorphometric analysis revealed that Cxcl10-/- mice are in part protected from reduced alveolar. These findings were related to the preserved spatial distribution of elastic fibers, reduced collagen deposition, and protection from macrophage recruitment/infiltration to the lungs in Cxcl10-/- mice during acute injury and regeneration. Complimentary, studies with cultured human and murine macrophages showed that hyperoxia induces Cxcl10 expression that in turn triggers M1-like activation and migration of macrophages through CXCR3. Finally, we demonstrated a temporal increase of macrophage-related CXCL10 in the lungs of infants with BPD. In conclusion, our data demonstrate macrophage-derived CXCL10 in experimental and clinical BPD that drives macrophage chemotaxis through CXCR3, causing pro-fibrotic lung remodeling and arrest of alveolarization. Thus, targeting the CXCL10-CXCR3 axis could offer a new therapeutic avenue for BPD.

The effect of TGF-ß1 polymorphisms on pulmonary disease progression in patients with cystic fibrosis.

BACKGROUND: Transforming Growth Factor-ß1 (TGF-ß1) is a genetic modifier in patients with cystic fibrosis (CF). Several single nucleotide polymorphisms (SNPs) of TGF-ß1 are associated with neutrophilic inflammation, lung fibrosis and loss of pulmonary function. AIM: The aim of this study was to assess the relationship between genetic TGF-ß1 polymorphisms and pulmonary disease progression in CF patients. Furthermore, the effect of TGF-ß1 polymorphisms on inflammatory cytokines in sputum was investigated. METHODS: 56 CF-patients and 62 controls were genotyped for three relevant SNPs in their TGF-ß1 sequence using the SNaPshot® technique. Individual "slopes" in forced expiratory volume in 1 s (FEV1) for all patients were calculated by using documented lung function values of the previous five years. The status of Pseudomonas aeruginosa (Pa) infection was determined. Sputum concentrations of the protease elastase, the serine protease inhibitor elafin and the cytokines IL-1ß, IL-8, IL-6, TNF-α were measured after a standardized sputum induction and processing. RESULTS: The homozygous TT genotype at codon 10 was associated with a lower rate of chronic Pa infection (p < 0.05). The heterozygous GC genotype at codon 25 was associated with lower lung function decline (p < 0.05). Patients with homozygous TT genotype at the promotor SNP showed higher levels of TNF-α (p < 0,05). Higher levels of TGF-ß1 in plasma were associated with a more rapid FEV1 decline over five years (p < 0.05). CONCLUSIONS: Our results suggest that polymorphisms in the TGF-ß1 gene have an effect on lung function decline, Pa infection as well as levels of inflammatory cytokines. Genotyping these polymorphisms could potentially be used to identify CF patients with higher risk of disease progression. TGF-ß1 inhibition could potentially be developed as a new therapeutic option to modulate CF lung disease.

Building global development strategies for cf therapeutics during a transitional cftr modulator era.

As CFTR modulator therapy transforms the landscape of cystic fibrosis (CF) care, its lack of uniform access across the globe combined with the shift towards a new standard of care creates unique challenges for the development of future CF therapies. The advancement of a full and promising CF therapeutics pipeline remains a necessary priority to ensure maximal clinical benefits for all people with CF. It is through collaboration across the global CF community that we can optimize the evaluation and approval process of new therapies. To this end, we must identify areas for which harmonization is lacking and for which efficiencies can be gained to promote ethical, feasible, and credible study designs amidst the changing CF care landscape. This article summarizes the counsel from core advisors across multiple international regions and clinical trial networks, developed during a one-day workshop in October 2019. The goal of the workshop was to identify, in consideration of the highly transitional era of CFTR modulator availability, the drug development areas for which global alignment is currently uncertain, and paths forward that will enable advancement of CF therapeutic development.

[CF Lung Disease - a German S3 Guideline: Module 2: Diagnostics and Treatment in Chronic Infection with Pseudomonas aeruginosa]. / S3-Leitlinie: Lungenerkrankung bei Mukoviszidose ­ Modul 2: Diagnostik und Therapie bei der chronischen Infektion mit Pseudomonas aeruginosa.

Cystic Fibrosis (CF) is the most common autosomal-recessive genetic disease affecting approximately 8000 people in Germany. The disease is caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene leading to dysfunction of CFTR, a transmembrane chloride channel. This defect causes insufficient hydration of the epithelial lining fluid which leads to chronic inflammation of the airways. Recurrent infections of the airways as well as pulmonary exacerbations aggravate chronic inflammation, lead to pulmonary fibrosis and tissue destruction up to global respiratory insufficiency, which is responsible for the mortality in over 90 % of patients. The main aim of pulmonary treatment in CF is to reduce pulmonary inflammation and chronic infection. Pseudomonas aeruginosa (Pa) is the most relevant pathogen in the course of CF lung disease. Colonization and chronic infection are leading to additional loss of pulmonary function. There are many possibilities to treat Pa-infection. This is a S3-clinical guideline which implements a definition for chronic Pa-infection and demonstrates evidence-based diagnostic methods and medical treatment for Pa-infection in order to give guidance for individual treatment options.

Pharmacokinetics and safety of an 8 week continuous treatment with once-daily versus twice-daily inhalation of tobramycin in cystic fibrosis patients.

OBJECTIVES: We evaluated the pharmacokinetics, safety and tolerability of two different continuous treatment regimens of tobramycin inhalation solution (TIS) in 29 cystic fibrosis (CF) patients chronically infected with Pseudomonas aeruginosa. PATIENTS AND METHODS: In this randomized, multicentre, open-label, two-period crossover study, TIS (300 mg/5 mL) was administered via PARI eFlow(®) rapid once daily and twice daily each for 8 weeks. Serum pharmacokinetics of these two regimens was analysed. Tobramycin levels were determined before the morning dose and at 30, 60 and 90 min after the end of nebulization in the middle and at the end of each 8 week cycle. At these timepoints, trough and peak serum tobramycin concentrations (Cmax, mg/L) as well as the area under the curve for 0-90 min of tobramycin (AUC0-90min) were assessed in order to evaluate the risk of systemic toxicity. Safety parameters and forced expiratory volume in 1 s (FEV1) were assessed. RESULTS: For once-daily treatment, tobramycin levels were 10% higher after 8 weeks compared with 4 weeks (AUC0-90min ratio = 1.096, 90% CI = 0.860-1.396, P = 0.5237). For twice-daily treatment, tobramycin levels after 8 weeks showed a 40% decrease compared with 4 weeks (AUC0-90min ratio = 0.608, 90% CI = 0.461-0.802, P = 0.0055). The AUC0-90min ratio at 8 weeks (once daily versus twice daily) did not differ significantly (AUC0-90min ratio = 0.749, 90% CI = 0.514-1.092, P = 0.2009). The mean FEV1 did not differ markedly compared between treatment periods or with baseline. No audiological or nephrotoxic side effects were noted. CONCLUSIONS: Continuous treatment with TIS (once daily or twice daily) over 8 weeks appears to be safe and tolerable.

Prevalence and molecular characterization of azole resistance in Aspergillus spp. isolates from German cystic fibrosis patients.

OBJECTIVES: Aspergillus spp. are the most frequently isolated filamentous fungi in the sputum of patients with cystic fibrosis (CF). Resistance to the azoles, the mainstay of current antifungal therapy, has been increasingly observed worldwide, but few data are available on the resistance of Aspergillus spp. in German CF patients. This study investigated the epidemiology of Aspergillus spp. and the molecular origin of azole resistance in a large German CF centre. METHODS: In total, 2677 respiratory samples from 221 CF patients collected between April 2010 and April 2013 were analysed; of these, 573 yielded Aspergillus spp., which were screened for azole resistance. Isolates with reduced susceptibility to itraconazole and/or voriconazole were tested according to the EUCAST reference procedure. Sequencing of cyp51A, the target of azole antifungals, was performed in all resistant isolates. RESULTS: Six isolates obtained from four patients were highly resistant to itraconazole (all identified as Aspergillus fumigatus sensu stricto); five of them were pan-azole resistant. The TR34/L98H mutation was the most frequent mutation identified in azole-resistant isolates (n = 4), followed by M220L and TR46/Y121F/T289A, a mutation previously reported from Belgium and the Netherlands only. Three of four patients harbouring azole-resistant A. fumigatus had not received any prior azole treatment. CONCLUSIONS: Resistance to azoles in Aspergillus spp. is still infrequent in German CF patients and is mainly caused by the TR34/L98H mutation. Worryingly, pan-azole-resistant TR46/Y121F/T289A has spread to Germany. Azole resistance has to be considered also in azole-naive CF patients and susceptibility testing of Aspergillus spp. isolates should be performed in all patients requiring treatment.

Cystic fibrosis as a rare cause of apple peel syndrome.

Apple peel atresia is a special form of intestinal atresia with absence of mesentery. It is most likely due to an intrauterine intestinal vascular accident and has been described with other anomalies. Meconium ileus can compromise blood supply causing intestinal atresia. Therefore, cystic fibrosis needs to be ruled out in apple peel syndrome.