Reversal of cylindrical bronchial dilatations in a subset of adults with cystic fibrosis treated with elexacaftor-tezacaftor-ivacaftor.

BACKGROUND: This study sought to evaluate the impact of elexacaftor-tezacaftor-ivacaftor (ETI) on lung structural abnormalities in adults with cystic fibrosis (awCF) with a specific focus on the reversal of bronchial dilatations. METHODS: Chest computed tomography (CT) performed prior to, and ≥12 months after initiation of ETI were visually reviewed for possible reversal of bronchial dilatations. AwCF with and without reversal of bronchial dilatation (the latter served as controls with 3 controls per case) were selected. Visual Brody score, bronchial and arterial diameters, and lung volume were measured on CT. RESULTS: Reversal of bronchial dilatation was found in 12/235 (5%) awCF treated with ETI. Twelve awCF with and 36 without reversal of bronchial dilatations were further analyzed (male=56%, mean age=31.6±8.5 years, F508del/F508del CFTR =54% and mean %predicted forced expiratory volume in 1 s=58.8%±22.3). The mean±sd Brody score improved overall from 79.4±29.8 to 54.8±32.3 (p<0.001). Reversal of bronchial dilatations was confirmed by a decrease in bronchial lumen diameter in cases from 3.9±0.9 mm to 3.2±1.1 mm (p<0.001), whereas it increased in awCF without reversal of bronchial dilatation (from 3.5±1.1 mm to 3.6±1.2 mm, p=0.002). Reversal of bronchial dilatations occurred in cylindrical (not varicose or saccular) bronchial dilatations. Lung volumes decreased by -6.6±10.7% in awCF with reversal of bronchial dilatation but increased by +2.3±9.6% in controls (p=0.007). CONCLUSION: Although bronchial dilatations are generally considered irreversible, ETI was associated with reversal, which was limited to the cylindrical bronchial dilatations subtype, and occurred in a small subset of awCF. Initiating ETI earlier in life may reverse early bronchial dilatations.

Acneiform Eruption Following Elexacaftor-Tezacaftor-Ivacaftor Treatment in Patients With Cystic Fibrosis.

Importance: A new treatment for cystic fibrosis combining 3 CFTR modulators-elexacaftor (ELX), tezacaftor (TEZ), and ivacaftor (IVA)-has recently been approved for cystic fibrosis treatment. The cutaneous adverse effects following treatment with this combination are poorly described in the literature. Objective: To describe the clinicopathological features and treatment response of ELX-TEZ-IVA-associated acneiform eruptions in patients with cystic fibrosis. Design, Setting, and Participants: This case series study was conducted in the Dermatology Department of Cochin Hospital, Paris, France, from July 2021 to June 2022 in collaboration with the Cochin Reference Center for Cystic Fibrosis. Referred patients were examined by senior dermatologists. All patients with cystic fibrosis treated with ELX-TEZ-IVA and referred for an acneiform rash were included. Exposures: Treatment with ELX-TEZ-IVA. Main Outcomes and Measures: Onset of acneiform rash, type of lesions, and degree of severity, as well as treatments initiated and response, were evaluated. When performed, skin biopsies were reviewed. Results: This study included 16 patients (11 women [68.7%]) with a median (range) age of 27 (22-38) years. Six patients (37.5%) developed new-onset acneiform rashes, whereas 10 patients (62.5%) had a relapse (5 patients) or worsening (5 patients) of previous acne. The median (range) onset of acneiform rash was 45 (15-150) days. At inclusion, 11 patients (68.7%) had facial hyperseborrhea, 15 patients (93.7%) had noninflammatory lesions, and 14 (87.5%) had inflammatory lesions of seborrheic regions. Four patients (25.0%) had severe acne with deep inflammatory lesions and pitted scars. A specific pathological pattern of necrotizing infundibular crystalline folliculitis was observed in 4 patients. Topical acne treatments, antibiotics, and isotretinoin were used successfully in these patients, resulting in partial or complete remission in 12 patients (85.7% of patients reevaluated). Conclusions and Relevance: This case series study found that acneiform eruption is an adverse event associated with ELX-TEZ-IVA treatment in patients with cystic fibrosis. Most patients developed mild lesions. However, isotretinoin treatment may be necessary in some patients. The mechanism of ELX-TEZ-IVA-associated acneiform eruption is currently unknown, but the observation of necrotizing infundibular crystalline folliculitis in biopsied patients may guide further exploration.

Otological Manifestations in Adults with Primary Ciliary Dyskinesia: A Controlled Radio-Clinical Study.

Primary ciliary dyskinesia (PCD) is a rare genetical disease characterized by an abnormal structure or function of the cilia, causing sinusitis, otitis, and bronchiectasis. Hearing loss affects 60% of PCD patients, but data are lacking concerning hearing and temporal bone imaging in adults. Our aim was to describe clinical and radiological ear disease in adults with genetically confirmed PCD. Data were recorded from January 2018 to December 2019. PCD patients were compared with controls with bronchiectasis without PCD. Clinical examination included otomicroscopy and auditory tests. A temporal bone CT scan (TBCT) was systematically performed. Seventeen patients (34 ears) were included in each group. The eardrums were abnormal in 25 (74%) PCD ears versus 8 (24%) ears in the controls (p < 0.05). Conductive hearing loss was more frequent in the PCD group (24% vs. 12% in controls). TBCT were abnormal in 94% PCD patients vs. 32% in the controls (p < 0.05). The Main CT-scan images in PCD were middle ear inflammation (65%), mastoid condensation (62%), or ossicular anomalies (35%). With its excellent sensitivity, TBCT gives typical arguments for PCD diagnosis, adding otological signs to the usual sinus CT signs (hypoplasia, aplasia). Systematic TBCT could be useful in the initial evaluation of patients with suspicion of PCD.

Diagnosis Yield and Safety of Surgical Biopsy in Interstitial Lung Diseases: A Prospective Study.

BACKGROUND: Surgical lung biopsy is essential in the diagnostic algorithm of interstitial lung disease (ILD) of unknown cause. Safety concerns have been recently reiterated. This study prospectively assessed the yield of diagnosis and safety of video-assisted thoracoscopic surgical lung biopsy (VATS-LB) for ILD diagnosis. METHODS: This prospective study, conducted in 6 ILD-referral Paris hospitals, included 103 patients with ILD. VATS-LB was proposed after initial multidisciplinary discussion. A final diagnosis was made after the procedure, during a second multidisciplinary discussion. The main outcome was to determine the final diagnoses and their proportion after VATS-LB. Other outcomes were the percentage of change in diagnosis and treatment propositions after VATS-LB and adverse events during 3 months after the operation, postoperative pulmonary function, quality of life, and pain. RESULTS: A definite diagnosis was reached in 87 patients (84.4%), and 16 remained unclassifiable (15.6%). After VATS-LB, the hypothesized diagnosis changed in 65 patients (63.1%) and treatment changed in 41 patients (39.8%). One patient died of acute exacerbation. In-hospital complications were predicted by a shorter preoperative 6-minute walking test distance and by forced vital capacity lower than 77%. Postoperative quality of life was not modified at 3 months, whereas forced vital capacity decreased slightly. Postoperative neuropathic pain was revealed in 5% of patients at 1 month and in 2% at 3 months. CONCLUSIONS: VATS-LB dramatically changed preoperative hypothetical diagnoses and treatment in ILD of unknown cause, with good patient survival in ILD referral centers.

"Il faut continuer à poser des questions" patient reported outcome measures in cystic fibrosis: An anthropological perspective.

BACKGROUND: People with cystic fibrosis (pwCF) are central in the development of patient-led assessment tools. Qualitative analysis of a frequently used CF-specific patient-reported outcome measure (PROM) sought patient recommendations for development of a new quality of life (QoL) tool. METHODS: We performed an inventory of PROMs, symptom-report and QoL tools used in clinical trials within the European Cystic Fibrosis Society Clinical Trial Network (ECFS-CTN) and in routine clinical practice among Cystic Fibrosis Europe and ECFS members. A qualitative study using cognitive interviews with pwCF and their caregivers reviewed the Cystic Fibrosis Questionnaire (CFQ), the French initial form of the Cystic Fibrosis Questionnaire-Revised (CFQ-R). RESULTS: Survey results from 33 countries revealed over 70 tools used in routine clinical practice, utilized by clinical specialists (n=124), pwCF/parents/carers (n=49) and other allied health professionals (n=60). The CFQ-R was the main PROM used in clinical trials. The qualitative study enrolled 99 pwCF, 6 to 11 years (n=31); 12 to 18 years (n=38); >18 years (n=30) and 26 parents. Inductive thematic analysis based on the CFQ, revealed 19 key themes. Themes common across all cohorts included burden of treatment, impact of disease on day-to-day life, relationships/family, stress/mood, and nutrition. Themes unique to individual groups included, treatment when not symptomatic for the paediatric group; education/studies and planning for the future for adolescents, impact of anxiety and depression on day-to-day life for adults, and for parents, questions addressing anxiety and their role as carers. CONCLUSIONS: Patient-centeredness is paramount in development of an up-to-date PROM in the era of novel therapies.

Topological data analysis reveals genotype-phenotype relationships in primary ciliary dyskinesia.

BACKGROUND: Primary ciliary dyskinesia (PCD) is a heterogeneous inherited disorder caused by mutations in approximately 50 cilia-related genes. PCD genotype-phenotype relationships have mostly arisen from small case series because existing statistical approaches to investigating relationships have been unsuitable for rare diseases. METHODS: We applied a topological data analysis (TDA) approach to investigate genotype-phenotype relationships in PCD. Data from separate training and validation cohorts included 396 genetically defined individuals carrying pathogenic variants in PCD genes. To develop the TDA models, 12 clinical and diagnostic variables were included. TDA-driven hypotheses were subsequently tested using traditional statistics. RESULTS: Disease severity at diagnosis, measured by forced expiratory volume in 1 s (FEV1) z-score, was significantly worse in individuals with CCDC39 mutations (compared to other gene mutations) and better in those with DNAH11 mutations; the latter also reported less neonatal respiratory distress. Patients without neonatal respiratory distress had better preserved FEV1 at diagnosis. Individuals with DNAH5 mutations were phenotypically diverse. Cilia ultrastructure and beat pattern defects correlated closely to specific causative gene groups, confirming these tests can be used to support a genetic diagnosis. CONCLUSIONS: This large scale, multi-national study presents PCD as a syndrome with overlapping symptoms and variations in phenotype according to genotype. TDA modelling confirmed genotype-phenotype relationships reported by smaller studies (e.g. FEV1 worse with CCDC39 mutation) and identified new relationships, including FEV1 preservation with DNAH11 mutations and diversity of severity with DNAH5 mutations.

Standardised clinical data from patients with primary ciliary dyskinesia: FOLLOW-PCD.

Clinical data on primary ciliary dyskinesia (PCD) are limited, heterogeneous and mostly derived from retrospective chart reviews, leading to missing data and unreliable symptoms and results of physical examinations. We need standardised prospective data collection to study phenotypes, severity and prognosis and improve standards of care. A large, international and multidisciplinary group of PCD experts developed FOLLOW-PCD, a standardised clinical PCD form and patient questionnaire. We identified existing forms for clinical data collection via the Better Experimental Approaches to Treat PCD (BEAT-PCD) COST Action network and a literature review. We selected and revised the content items with the working group and patient representatives. We then revised several drafts in an adapted Delphi process, refining the content and structure. FOLLOW-PCD has a modular structure, to allow flexible use based on local practice and research focus. It includes patient-completed versions for the modules on symptoms and lifestyle. The form allows a comprehensive standardised clinical assessment at baseline and for annual reviews and a short documentation for routine follow-up. It can either be completed using printable paper forms or using an online REDCap database. Data collected in FOLLOW-PCD version 1.0 is available in real-time for national and international monitoring and research. The form will be adapted in the future after extensive piloting in different settings and we encourage the translation of the patient questionnaires to multiple languages. FOLLOW-PCD will facilitate quality research based on prospective standardised data from routine care, which can be pooled between centres, to provide first-line and real-time evidence for clinical decision-making.

TTC12 Loss-of-Function Mutations Cause Primary Ciliary Dyskinesia and Unveil Distinct Dynein Assembly Mechanisms in Motile Cilia Versus Flagella.

Cilia and flagella are evolutionarily conserved organelles whose motility relies on the outer and inner dynein arm complexes (ODAs and IDAs). Defects in ODAs and IDAs result in primary ciliary dyskinesia (PCD), a disease characterized by recurrent airway infections and male infertility. PCD mutations in assembly factors have been shown to cause a combined ODA-IDA defect, affecting both cilia and flagella. We identified four loss-of-function mutations in TTC12, which encodes a cytoplasmic protein, in four independent families in which affected individuals displayed a peculiar PCD phenotype characterized by the absence of ODAs and IDAs in sperm flagella, contrasting with the absence of only IDAs in respiratory cilia. Analyses of both primary cells from individuals carrying TTC12 mutations and human differentiated airway cells invalidated for TTC12 by a CRISPR-Cas9 approach revealed an IDA defect restricted to a subset of single-headed IDAs that are different in flagella and cilia, whereas TTC12 depletion in the ciliate Paramecium tetraurelia recapitulated the sperm phenotype. Overall, our study, which identifies TTC12 as a gene involved in PCD, unveils distinct dynein assembly mechanisms in human motile cilia versus flagella.

Follow-Up and Management of Chronic Rhinosinusitis in Adults with Primary Ciliary Dyskinesia: Review and Experience of Our Reference Centers.

Chronic rhinosinusitis is the foremost manifestation in adult patients with primary ciliary dyskinesia (PCD). We present a retrospective series of 41 adult patients with a confirmed diagnosis of PCD followed in our reference centers. As part of the diagnostic work up in our centers, sinus computed tomography scans (CTs) are systematically performed. All patients also undergo a sampling of purulent secretions sampled from the middle meatus under endoscopic view for bacteriological analysis. In our series, CT opacities were consistent in all the patients, as well as mainly partial and located in ethmoid cells (100% of patients) and in maxillary sinuses (85.4% of patients), and stayed stable over time. In the 31 patients who had purulent secretions, bacteriological culture showed at least one bacterium in 83.9% (n = 26). There was no significant difference in positive cultures for Pseudomonas aeruginosa in patients >40 years old versus those <40 (p = 0.17; Fisher). Surgical management was performed in only 19% of patients in order to improve sinonasal mechanical drainage. Our data support the hypothesis that the sinuses can be considered as a bacterial reservoir. From this retrospective study, we have introduced several changes into our routine clinical practice in our reference centers. Based on our analyses, medical and surgical treatments benefit from incorporating bacteriological information and sinonasal symptoms much more than CT scan evaluation alone. All patients now undergo systematically an annual simultaneous bacteriological sampling of the middle meatus and sputum to follow the relationship between ENT and lung disease and to help to antibiotic therapy strategy.

Critical Evaluation of Sinonasal Disease in 64 Adults with Primary Ciliary Dyskinesia.

To date, no study precisely described ear, nose and throat (ENT) disease in adults with primary ciliary dyskinesia (PCD) and its relationship with ciliary function/ultrastructure. A retrospective study of standardized ENT data (exam, audiogram, sinus Computed tomography (CT), and bacteriology) was conducted in 64 adults with confirmed PCD who were followed in two ENT reference centers. Rhinorrhoea and hearing loss were the main symptoms. Symptom scores were higher in older patients. Nasal endoscopy was abnormal in all patients except one, showing nasal polyps in one-third of the patients and stagnant nasal mucus secretions in 87.5% of the patients. Sinus CT opacities were mainly incomplete and showed one-third of the patients with sinus hypoplasia and/or agenesis. Middle meatus mainly grew Haemophilus influenzae, Streptoccocus pneumoniae and Pseudomonas aeruginosa. Otitis media with effusion (OME), which is constant in childhood, was diagnosed in less than one-quarter of the patients. In two-thirds of the patients, audiogram showed hearing loss that was sensorineural in half of the patients. ENT disease severity was not correlated with ciliary function and ultrastructure, but the presence of OME was significantly associated with a forced expiratory volume (FEV1) < 70%. Rhinosinusitis is the most common clinical feature of PCD in adults, while OME is less frequent. The presence of active OME in adults with PCD could be a severity marker of lung function and lead to closer monitoring.

Automated computed tomographic scoring of lung disease in adults with primary ciliary dyskinesia.

BACKGROUND: The present study aimed to develop an automated computed tomography (CT) score based on the CT quantification of high-attenuating lung structures, in order to provide a quantitative assessment of lung structural abnormalities in patients with Primary Ciliary Dyskinesia (PCD). METHODS: Adult (≥18 years) PCD patients who underwent both chest CT and spirometry within a 6-month period were retrospectively included. Commercially available lung segmentation software was used to isolate the lungs from the mediastinum and chest wall and obtain histograms of lung density. CT-density scores were calculated using fixed and adapted thresholds based on various combinations of histogram characteristics, such as mean lung density (MLD), skewness, and standard deviation (SD). Additionally, visual scoring using the Bhalla score was performed by 2 independent radiologists. Correlations between CT scores, forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were evaluated. RESULTS: Sixty-two adult patients with PCD were included. Of all histogram characteristics, those showing good positive or negative correlations to both FEV1 and FVC were SD (R = - 0.63 and - 0.67; p < 0.001) and Skewness (R = 0.67 and 0.67; p < 0.001). Among all evaluated thresholds, the CT-density score based on MLD + 1SD provided the best negative correlation with both FEV1 (R = - 0.68; p < 0.001) and FVC (R = - 0.71; p < 0.001), close to the correlations of the visual score (R = - 0.60; p < 0.001 for FEV1 and R = - 0.62; p < 0.001, for FVC). CONCLUSIONS: Automated CT scoring of lung structural abnormalities lung in primary ciliary dyskinesia is feasible and may prove useful for evaluation of disease severity in the clinic and in clinical trials.

A prospective analysis of unplanned patient-initiated contacts in an adult cystic fibrosis centre.

BACKGROUND: Timely response should be provided when patients contact the cystic fibrosis (CF) centre in between scheduled visits. Little data exist on unplanned patient-initiated contacts in CF adults. METHODS: A two-stage prospective study was undertaken from 1 January to 31 December 2015 at Cochin Hospital, Paris (France). The first stage included all adults (≥18 years) who initiated unplanned contacts to the CF centre over four months. Four physicians and three nurses systematically recorded unplanned patient-initiated contacts. The data was analysed to determine why and how patients contacted the CF centre and time spent responding to their request(s). The second stage (one physician, three nurses) lasted twelve months and explored whether high contact frequency was associated with disease severity, using multivariate logistic regression. RESULTS: In the first stage, 259 of 410 patients (63%) initiated at least one unplanned contact, corresponding to 1067 contacts over 4 months. Patients favoured email with physicians (61% of contacts) and telephone with nurses (87% of contacts). Total time spent by the 7 caregivers on providing responses was 8 h/work week. Reasons for contacting the CF centre varied greatly, but <20% of contacts were directly related to symptom management. In the second stage, 180 of 212 patients (85%) initiated 1876 contacts over 12 months. Factors associated with ≥5 contacts/year were female sex, FEV1 ≤ 30% predicted, ≥5 physician visits/year, and ≥ 1 hospital admission/year. CONCLUSIONS: Answering unplanned patient-initiated contacts represented a significant workload for CF caregivers. Increased disease severity was associated with high contact frequency.

Real-life initiation of lumacaftor/ivacaftor combination in adults with cystic fibrosis homozygous for the Phe508del CFTR mutation and severe lung disease.

OBJECTIVE: To investigate the short-term adverse events and effectiveness of lumacaftor/ivacaftor combination treatment in adults with cystic fibrosis (CF) and severe lung disease in a real life setting. METHODS: A multicentre observational study investigated adverse events, treatment discontinuation, FEV1 and body mass index (BMI) one month and three months after lumacaftor/ivacaftor initiation in adults with CF and FEV1 below 40% predicted. RESULTS: Respiratory adverse events (AEs) were reported by 27 of 53 subjects (51%) and 16 (30%) discontinued treatment. The mean absolute change in FEV1 was +2.06% after one month of treatment (P=0.086) and +3.19% after 3 months (P=0.009). BMI was unchanged. CONCLUSIONS: Treatment with lumacaftor/ivacaftor in patients with CF and severe lung disease was discontinued more frequently than reported in clinical trials, due to respiratory AEs. Nevertheless, the patients who continued treatment had an increase in lung function comparable to what was observed in pivotal trials.

Clinical characteristics, functional respiratory decline and follow-up in adult patients with primary ciliary dyskinesia.

INTRODUCTION: Primary ciliary dyskinesia (PCD) is a genetic disease characterised by abnormalities in ciliary function, responsible for chronic pulmonary and sinonasal diseases. Adult clinical features and outcome are poorly described. OBJECTIVES: To assess the clinical characteristics and disease progression in adults with PCD. METHODS: Bicentric retrospective study, focusing on adults (≥18 years) with an asserted diagnosis of PCD based on the presence of bronchiectasis with typical ultrastructural defect of cilia and/or situs inversus (SI). Clinical symptoms, respiratory function, extent of bronchiectasis, microbiology and molecular analysis were assessed. Results are expressed as median (25th; 75th centile). RESULTS: 78 patients were included with a median follow-up of 8.1 years. 91% of patients had respiratory symptoms and 95% had chronic rhinosinusitis. Half of ultrastructural defects concerned dynein arms. Respiratory function was significantly lower in women (FEV1=60% predicted (50; 76), vs 77% (62; 95), p=0.009) and in patients with chronic airway Pseudomonas aeruginosa (PA, n=21) infection (FEV1=60% (48; 71) vs 75% (55; 89), p=0.04). FEV1 was associated with gender (regression coefficient for men =13.8, p=0.009), chest CT score (r=-0.42, p<0.001) but not with age at diagnosis, SI or body mass index. FEV1 decline was -13.4 mL/year (-42.8; +11.9) and was greater in women (-29.3 mL/year, (-59.7; -11.9), vs -2.0 mL/year (-26.9; +25.4), p=0.002). Three patients had severe respiratory failure. CONCLUSIONS: Alteration of respiratory function in adults with PCD is heterogeneous and usually moderate but appears more severe in women and in patients with chronic PA infection. Only 4% of patients develop chronic respiratory failure.

CFTR and/or pancreatitis susceptibility genes mutations as risk factors of pancreatitis in cystic fibrosis patients?

BACKGROUND/OBJECTIVES: Currently, factors that promote the occurrence of pancreatitis episodes in patients affected with cystic fibrosis (CF) and pancreatic sufficiency (PS) are largely unknown. METHODS: Six genes involved in pancreatitis or in ion transport into the pancreatic duct were investigated by next generation sequencing in 59 adult CF-PS patients with two identified CF mutations. Data on predisposing environmental factors were also recorded. RESULTS: 19 experienced at least one episode of acute pancreatitis (AP) (AP+) and 40 patients did not (AP-). No influence of environmental factor was evidenced. No specific CFTR genotype was found predictive of pancreatitis. Patients sharing the same CFTR genotype may or may not experience AP episodes. Frequent and rare missense variants were found in 78.9% patients in group AP+ and 67.5% in group AP- but a few of them were pathogenic. CONCLUSIONS: AP or recurrent AP (RAP) is a frequent complication in our series of adult CF-PS patients. The majority of mild CFTR mutations found in group AP+ were located in the first transmembrane region. No clear other genetic factor could be found predictive of AP/RAP. Further experiments in large homogenous cohorts of CF-PS patients, including whole genome sequencing, may identify genetic predisposing factors to pancreatitis.

Renin-associated hypertension after bronchial artery embolization in cystic fibrosis.

Bronchial artery embolization is the recommended therapy for massive hemoptysis in patients with cystic fibrosis (CF). We report on two cases of multiple renal infarcts and renin-associated hypertension and hypokalemia occurring in CF adults after bronchial artery embolizations. These complications were presumably related to crossing of small calibrated microspheres through arteriovenous anastomoses. Although hypokalemia resolved rapidly, hypertension persisted at least 6 months and its control required multiple antihypertensive agents. Physicians should be aware of this potentially severe, but previously unreported, complication of bronchial artery embolization.

DCTN4 as a modifier of chronic Pseudomonas aeruginosa infection in cystic fibrosis.

BACKGROUND AND AIMS: Pseudomonas aeruginosa (Pa) infection in cystic fibrosis (CF) patients is associated with worse long-term pulmonary disease and shorter survival, and chronic Pa infection (CPA) is associated with reduced lung function, faster rate of lung decline, increased rates of exacerbations and shorter survival. By using exome sequencing and extreme phenotype design, it was recently shown that isoforms of dynactin 4 (DCTN4) may influence Pa infection in CF, leading to worse respiratory disease. The purpose of this study was to investigate the role of DCTN4 missense variants on Pa infection incidence, age at first Pa infection and chronic Pa infection incidence in a cohort of adult CF patients from a single centre. METHODS: Polymerase chain reaction and direct sequencing were used to screen DNA samples for DCTN4 variants. RESULTS: A total of 121 adult CF patients from the Cochin Hospital CF centre have been included, all of them carrying two CFTR defects: 103 developed at least 1 pulmonary infection with Pa, and 68 patients of them had CPA. DCTN4 variants were identified in 24% (29/121) CF patients with Pa infection and in only 17% (3/18) CF patients with no Pa infection. Of the patients with CPA, 29% (20/68) had DCTN4 missense variants vs 23% (8/35) in patients without CPA. Interestingly, p.Tyr263Cys tend to be more frequently observed in CF patients with CPA than in patients without CPA (4/68 vs 0/35), and DCTN4 missense variants tend to be more frequent in male CF patients with CPA bearing two class II mutations than in male CF patients without CPA bearing two class II mutations (P = 0.06). CONCLUSIONS: Our observations reinforce that DCTN4 missense variants, especially p.Tyr263Cys, may be involved in the pathogenesis of CPA in male CF.

Reduced risk of nontuberculous mycobacteria in cystic fibrosis adults receiving long-term azithromycin.

BACKGROUND: Azithromycin reduces exacerbations in cystic fibrosis (CF) patients. Our aim was to investigate its association with nontuberculous mycobacteria isolation and macrolide susceptibility. METHODS: From 2006 to 2010, all adult CF subjects at Cochin Hospital (Paris, France) harboring at least one positive NTM isolate were identified (Cases). In a nested case-control study, each Case was individually matched for age and gender with up to 4 CF adults with no NTM isolate (Controls). Clinical data at the time of first NTM isolate (index date) in Cases were compared with those of Controls using multivariate conditional regression analysis. RESULTS: CF subjects with positive NTM isolates (Cases, n=41) were matched to 155 Controls. Among Cases, 48.7% had isolates from Mycobacterium avium complex and 58.5% from Mycobacterium abscessus complex, and 31 Cases fulfilled the 2007 American Thoracic Society criteria for NTM infection (ATS+ Cases). Cases and ATS+ Cases were more likely to have low body mass index and colonization with Aspergillus fumigatus. Azithromycin was associated with a two-fold reduction in NTM isolates. Only one M. avium complex isolate had acquired macrolide resistance. CONCLUSION: These data suggest that azithromycin is a primary prophylaxis for NTM infection in CF adults.