The international primary ciliary dyskinesia cohort (iPCD Cohort): methods and first results

Primary Ciliary Dyskinesia: A Clinical Review

Primary ciliary dyskinesia (PCD) is a rare, genetically heterogeneous, motile ciliopathy, characterized by neonatal respiratory distress, recurrent upper and lower respiratory tract infections, subfertility, and laterality defects. Diagnosis relies on a combination of tests for confirmation, including nasal nitric oxide (nNO) measurements, high-speed videomicroscopy analysis (HSVMA), immunofluorescent staining, axonemal ultrastructure analysis via transmission electron microscopy (TEM), and genetic testing. Notably, there is no single gold standard confirmatory or exclusionary test. Currently, 54 causative genes involved in cilia assembly, structure, and function have been linked to PCD; this rare disease has a spectrum of clinical manifestations and emerging genotype-phenotype relationships. In this review, we provide an overview of the structure and function of motile cilia, the emerging genetics and pathophysiology of this rare disease, as well as clinical features associated with motile ciliopathies, novel diagnostic tools, and updates on genotype-phenotype relationships in PCD.

Outcomes of Endoscopic Sinus Surgery for Chronic Rhinosinusitis in Adults with Primary Ciliary Dyskinesia

Introduction  Primary ciliary dyskinesia (PCD) is a rare inherited disease associated with impairment of mucociliary transport and, consequently, with a high incidence of chronic rhinosinusitis. For patients with chronic rhinosinusitis who remain symptomatic despite medical treatment, endoscopic sinus surgery is a safe and effective therapeutic option. However, to date, no studies have been found evaluating the effect of surgery on the quality of life associated with the effect on olfaction and nasal endoscopy findings of patients with primary ciliary dyskinesia and chronic rhinosinusitis. Objective  To describe the effect of endoscopic sinus surgery on the quality of life, on olfaction, and on nasal endoscopy findings of adults with PCD and chronic rhinosinusitis. Methods  Four patients who underwent endoscopic sinus surgery were included. The Sinonasal Outcome Test-22 (SNOT-22) score, the Nasal Obstruction Symptom Evaluation (NOSE) questionnaire, and the Lund-Kennedy score were collected preoperatively and at 3 and 6 months postoperatively. The olfaction as assessed with the University of Pennsylvania Smell Identification Test (UPSIT), which was administered preoperatively and 3 months postoperatively. Results  A total of 4 patients with a mean age of 39.3 years old (3 men and 1 woman) completed the study. All patients showed clinically significant improvement in the SNOT-22, NOSE, and Lund-Kennedy scores at 3 months postoperatively, and this improvement was sustained throughout the follow-up period. However, olfaction did not improve after surgery. Conclusion  The endoscopic sinus surgery treatment of chronic rhinosinusitis in adults with PCD was associated with improvement in quality of life and endoscopic findings. However, no improvement in olfaction was demonstrated. Studies with a larger number of patients and control groups should help confirm these findings.

Challenges in Diagnosing Primary Ciliary Dyskinesia in a Brazilian Tertiary Hospital

Primary ciliary dyskinesia (PCD) causes cellular cilia motility alterations, leading to clinical manifestations in the upper and lower respiratory tract and situs abnormalities. The PCD diagnosis was improved after the inclusion of diagnostic tools, such as transmission electron microscopy and genetic screening; however, the PCD screening is a challenge yet. In this context, we aimed to describe the clinical, genetic, and ultra-ciliary characteristics in individuals with clinical suspicion of PCD (cPCD) from a Brazilian Tertiary Hospital. An observational study was carried out with individuals during the follow-up between 2011 and 2021. The individuals were submitted to clinical questionnaires, transmission electron microscopy, and genetic screening for pathogenic variants in PCD-related genes. Those patients were classified according to the degree of suspicion for PCD. In our study, we enrolled thirty-seven cPCD individuals; 20/37 (54.1%) had chronic rhinosinusitis, 28/37 (75.6%) had bronchiectasis, and 29/37 (78.4%) had recurrent pneumonia. A total of 17/37 (45.9%) individuals had transmission electron microscopy or genetic confirmation of PCD; 10 individuals had at least one positive pathogenic genetic variant in the PCD-related genes; however, only seven patients presented a conclusive result according to the American College of Medical Genetics and Genomics and the Association for Molecular Pathology with two pathogenic variants in homozygous or compound heterozygous. The median age at diagnosis was 13 years, and the median time between suspicion and diagnosis was four years. Sixteen patients had class I electron microscopy alterations, seven had class II alterations, and 14 had normal transmission electron microscopy according to the international consensus guideline for reporting transmission electron microscopy results in the diagnosis of PCD (BEAT-PCD TEM Criteria). Genetic screening for pathogenic variants in PCD-related genes and transmission electron microscopy can help determine the PCD diagnosis; however, they are still unavailable to all individuals with clinical suspicion in Brazil. We described ultrastructural alterations found in our population along with the identification of pathogenic variants in PCD-related genes.

Translation of the quality of life questionnaire for primary ciliary dyskinesia (QOL-PCD) into Hebrew: The Israeli experience

BACKGROUND

Patients with primary ciliary dyskinesia (PCD) have chronic morbidities affecting their quality of life (QOL). Health-related QOL (HRQOL) has been recognized as an important tool for assessing the burden of PCD on patients and their families. A PCD-specific HRQOL questionnaire (QOL-PCD) was developed and validated for the English-speaking populations. Still, it has not yet been translated into Hebrew or adapted for Israeli PCD patients.

METHODS

This describes our translation of the original English version of QOL-PCD into a Hebrew version. The process involved forward translation by independent translators, construction of a consensus version, back-translation into the original English version, analysis by the expert committee, and a pretest. The pretest was administered to 20 participants with PCD (the patients and the parents of minor patients) to assess the feasibility and practicality of the tool. Scale and item indices (scale-level content validity index [S-CVI] and item-level content validity index [I-CVI]) were calculated for content validity.

RESULTS

All study participants understood the final Hebrew version that the expert committee had approved with no difficulty. The instrument had satisfactory (>0.80) content validity, with S-CVI indexes of 0.99 for the adult version, 0.86 for the parental version, 0.95 for the adolescent version, and 1.00 for the child version.

CONCLUSION

The English version of a QOL-PCD was translated into Hebrew and adapted in Israel. This translation is a valid instrument to assess HRQOL in Hebrew-speaking patients with PCD and their family members. It may be helpful for PCD patient management and research in Israel.

Chronic airway disease in primary ciliary dyskinesia—spiced with geno–phenotype associations

Primary ciliary dyskinesia (PCD) can be defined as a multiorgan ciliopathy with a dominant element of chronic airway disease affecting the nose, sinuses, middle ear, and in particular, the lower airways. Although most patients with PCD are diagnosed during preschool years, it is obvious that the chronic lung disease starts its course already from birth. The many faces of the clinical picture change, as does lung function, structural lung damage, the burden of infection, and of treatment throughout life. A markedly severe neutrophil inflammation in the respiratory tract seems pervasive and is only to a minimal extent ameliorated by a treatment strategy, which is predominantly aimed at bacterial infections. An ever‐increasing understanding of the different aspects, their interrelationships, and possible different age courses conditioned by the underlying genotype is the focus of much attention. The future is likely to offer personalized medicine in the form of mRNA therapy, but to that end, it is of utmost importance that all patients with PCD be carefully characterized and given a genetic diagnosis. In this narrative review, we have concentrated on lower airways and summarized the current understanding of the chronic airway disease in this motile ciliopathy. In addition, we highlight the challenges, gaps, and opportunities in PCD lung disease research.

Respiratory symptoms of Swiss people with Primary Ciliary Dyskinesia

Background

Mostly derived from chart reviews, where symptoms are recorded in a nonstandardised manner, clinical data about primary ciliary dyskinesia (PCD) are inconsistent, which leads to missing and unreliable information. We assessed the prevalence and frequency of respiratory and ear symptoms and studied differences by age and sex among an unselected population of Swiss people with PCD.

Methods

We sent a questionnaire that included items from the FOLLOW-PCD standardised questionnaire to all Swiss PCD registry participants.

Results

We received questionnaires from 74 (86%) out of 86 invited persons or their caregivers (median age 23 years, range 3–73 years), including 68% adults (≥18 years) and 51% females. Among participants, 70 (94%) reported chronic nasal symptoms; most frequently runny nose (65%), blocked nose (55%) or anosmia (38%). Ear pain and hearing problems were reported by 58% of the participants. Almost all (99%) reported cough and sputum production. The most common chronic cough complications were gastro-oesophageal reflux (n=11; 15%), vomiting (n=8; 11%) and urinary incontinence (n=6; 8%). Only nine (12%) participants reported frequent wheeze, which occurred mainly during infection or exercise, while 49 (66%) reported shortness of breath, and 9% even at rest or during daily activities. Older patients reported more frequent nasal symptoms and shortness of breath. We found no difference by sex or ultrastructural ciliary defect.

Conclusion

This is the first study to describe patient-reported PCD symptoms. The consistent collection of standardised clinical data will allow us to better characterise the phenotypic variability of the disease and study disease course and prognosis.

Detailed information about patient-reported PCD symptoms will help characterise the phenotypic variability of the disease and could inform the development of individualised treatment strategies for patientshttps://bit.ly/363Zb4T

Lower airway clinical outcome measures for use in primary ciliary dyskinesia research: a scoping review

Objectives

Disease-specific, well-defined and validated clinical outcome measures are essential in designing research studies. Poorly defined outcome measures hamper pooling of data and comparisons between studies. We aimed to identify and describe pulmonary outcome measures that could be used for follow-up of patients with primary ciliary dyskinesia (PCD).

Methods

We conducted a scoping review by systematically searching MEDLINE, Embase and the Cochrane Database of Systematic Reviews online databases for studies published from 1996 to 2020 that included ≥10 PCD adult and/or paediatric patients.

Results

We included 102 studies (7289 patients). 83 studies reported on spirometry, 11 on body plethysmography, 15 on multiple-breath washout, 36 on high-resolution computed tomography (HRCT), 57 on microbiology and 17 on health-related quality of life. Measurement and reporting of outcomes varied considerably between studies (e.g. different scoring systems for chest HRCT scans). Additionally, definitions of outcome measures varied (e.g. definition of chronic colonisation by respiratory pathogen), impeding direct comparisons of results.

Conclusions

This review highlights the need for standardisation of measurements and reporting of outcome measures to enable comparisons between studies. Defining a core set of clinical outcome measures is necessary to ensure reproducibility of results and for use in future trials and prospective cohorts.

Study protocol: the ear-nose-throat (ENT) prospective international cohort of patients with primary ciliary dyskinesia (EPIC-PCD)

INTRODUCTION

Primary ciliary dyskinesia (PCD) is a rare, genetic, multiorgan disease with an estimated prevalence of 1 in 10 000. It affects mainly the upper and lower airways due to impaired mucociliary clearance. Almost all patients have sinonasal or otologic (ear-nose-throat, ENT) problems, although the ENT clinical phenotype may present great variability. Despite that, data on PCD ENT manifestations are scarce and based on small single-centre studies. To date, we know little about the spectrum and severity of PCD ENT disease, its association with lung disease, its course over life and its determinants of prognosis.This study protocol describes the aims and methods of the first prospective, observational, multinational cohort study focusing on ENT disease in patients with PCD.

METHODS AND ANALYSIS

The ENT prospective international cohort of patients with PCD (EPIC-PCD) is a prospective standardised observational clinical cohort set up as a multinational multicentre study, embedded into routine patient care. It aims to longitudinally characterise ENT disease in patients with PCD and its association with lung disease, and to identify determinants of its prognosis. Patients of all ages, diagnosed with PCD who undergo an ENT clinical assessment at least once a year at one of the participating centres will be invited to participate. Collected data include diagnostic test results, results of ENT examinations, lung function measurements, information on management of ENT disease and patient-reported data on clinical symptoms and health-related quality of life (QoL). Data are collected using the standardised PCD-specific FOLLOW-PCD form and the validated QoL-PCD questionnaire.

ETHICS AND DISSEMINATION

The study has been reviewed and approved by the Human Research Ethics Committees at all participating centres, based on local legislation. The results of the study will be published in scientific journals, presented at scientific conferences and disseminated to participants and national patient organisations.

TRIAL REGISTRATION

NCT04611516.

Analysis of the clinical features of Japanese patients with primary ciliary dyskinesia

OBJECTIVE

Primary ciliary dyskinesia (PCD) is a rare hereditary disease. Most reports of PCD in Japan are case reports, and clinical analysis has not been performed. Differences in the causative genes might affect the clinical features in different ethnic groups. The purpose of this study was to clarify the clinical features of Japanese patients with PCD.

METHODS

We performed a retrospective chart review of PCD patients seen at Mie University Hospital and patients whose blood samples were sent to us for genetic analysis from 2011 to 2020. Data on the following items were collected and analyzed: age at first visit to the hospital, age at diagnosis of PCD, process of referral to our facility, chief complaint, situs status, PrImary CiliARy DyskinesiA Rule (PICADAR) score, nasal nitric oxide concentration, otoscopic findings, rhinoscopic findings, and paranasal computed tomography scan findings.

RESULTS

Sixty-seven patients (24 male, 43 female) were diagnosed with PCD during the study period. Age at diagnosis ranged from 2 months to 69 years (median, 17 years). Respiratory symptoms (77%) were the most common complaint, followed by nasal (15%) and aural (8%) symptoms. Situs inversus was present in 17 (25%) cases. Only 2 cases had congenital cardiac anomalies. The mean PICADAR score was 7.3 (range, 3-14) points. Approximately 50% of tympanic membranes showed retraction, suggesting otitis media with effusion. The mean Lund-Mackay score was 12.8 (range, 7-17) points, suggesting that the radiographic findings were not always severe. There was no significant difference in the total Lund-Mackay score between patients with and without situs inversus (12.7 vs. 12.6, respectively).

CONCLUSION

Situs inversus was present in 25% of Japanese PCD patients, which is much lower than observed in other countries. This is a result of differences in the major disease-causing genes. The general rule that "situs inversus is observed in approximately 50% of PCD patients" cannot be applied, at least, in Japanese PCD patients.

Primary Ciliary Dyskinesia

Primary ciliary dyskinesia (PCD) is an inherited cause of bronchiectasis. The estimated PCD prevalence in children with bronchiectasis is up to 26% and in adults with bronchiectasis is 1 to 13%. Due to dysfunction of the multiple motile cilia of the respiratory tract patients suffer from poor mucociliary clearance. Clinical manifestations are heterogeneous; however, a typical patient presents with chronic productive cough and rhinosinusitis from early life. Other symptoms reflect the multiple roles of motile cilia in other organs and can include otitis media and hearing loss, infertility, situs inversus, complex congenital heart disease, and more rarely other syndromic features such as hydrocephalus and retinitis pigmentosa. Awareness, identification, and diagnosis of a patient with PCD are important for multidisciplinary care and genetic counseling. Diagnosis can be pursued through a multitest pathway which includes the measurement of nasal nitric oxide, sampling the nasal epithelium to assess ciliary function and structure, and genotyping. Diagnosis is confirmed by the identification of a hallmark ultrastructural defect or pathogenic mutations in one of > 45 PCD causing genes. When a diagnosis is established management is centered around improving mucociliary clearance through physiotherapy and treatment of infection with antibiotics. The first international randomized controlled trial in PCD has recently been conducted showing azithromycin is effective in reducing exacerbations. It is likely that evidence-based PCD-specific management guidelines and therapies will be developed in the near future. This article examines prevalence, clinical features, diagnosis, and management of PCD highlighting recent advances in basic science and clinical care.

Properties of Non-Aminoglycoside Compounds Used to Stimulate Translational Readthrough of PTC Mutations in Primary Ciliary Dyskinesia

Primary ciliary dyskinesia (PCD) is a rare disease with autosomal recessive inheritance, caused mostly by bi-allelic gene mutations that impair motile cilia structure and function. Currently, there are no causal treatments for PCD. In many disease models, translational readthrough of premature termination codons (PTC-readthrough) induced by aminoglycosides has been proposed as an effective way of restoring functional protein expression and reducing disease symptoms. However, variable outcomes of pre-clinical trials and toxicity associated with long-term use of aminoglycosides prompt the search for other compounds that might overcome these problems. Because a high proportion of PCD-causing variants are nonsense mutations, readthrough therapies are an attractive option. We tested a group of chemical compounds with known PTC-readthrough potential (ataluren, azithromycin, tylosin, amlexanox, and the experimental compound TC007), collectively referred to as non-aminoglycosides (NAGs). We investigated their PTC-readthrough efficiency in six PTC mutations found in Polish PCD patients, in the context of cell and cilia health, and in comparison to the previously tested aminoglycosides. The NAGs did not compromise the viability of the primary nasal respiratory epithelial cells, and the ciliary beat frequency was retained, similar to what was observed for gentamicin. In HEK293 cells transfected with six PTC-containing inserts, the tested compounds stimulated PTC-readthrough but with lower efficiency than aminoglycosides. The study allowed us to select compounds with minimal negative impact on cell viability and function but still the potential to induce PTC-readthrough.

Implementation of multigene panel NGS diagnosis in the national primary ciliary dyskinesia cohort of Cyprus: An island with a high disease prevalence

We aimed to determine a genetic diagnosis in the national primary ciliary dyskinesia (PCD) cohort of Cyprus, an island with a high disease prevalence. We used targeted next-generation sequencing (NGS) of 39 PCD genes in 48 patients of Greek-Cypriot and other ancestries. We achieved a molecular diagnosis in 74% of the unrelated families tested. We identified 24 different mutations in 11 genes, 12 of which are novel. Homozygosity was more common in Greek-Cypriot than non-Greek-Cypriot patients (88% vs. 46.2%, p = .016). Four mutations (DNAH11:c.5095-2A>G, CFAP300:c.95_103delGCCGGCTCC, TTC25:c.716G>A, RSPH9:c.670+2T>C) were found in 74% of the diagnosed Greek-Cypriot families. Patients with RSPH9 mutations demonstrated higher nasal nitric oxide (57 vs. 15 nl/min, p <.001), higher forced expiratory volume in 1 s (-0.89 vs. -2.37, p = .018) and forced vital capacity (-1.00 vs. -2.16, p = .029) z scores than the rest of the cohort. Targeted multigene-panel NGS is an efficient tool for early diagnosis of PCD, providing insight into genetic disease epidemiology and improved patient stratification.

Respiratory Distress in the Newborn with Primary Ciliary Dyskinesia

Primary ciliary dyskinesia (PCD) is inherited in a predominantly autosomal recessive manner with over 45 currently identified causative genes. It is a clinically heterogeneous disorder that results in a chronic wet cough and drainage from the paranasal sinuses, chronic otitis media with hearing impairment as well as male infertility. Approximately 50% of patients have situs inversus totalis. Prior to the development of chronic oto-sino-pulmonary symptoms, neonatal respiratory distress occurs in more than 80% of patients as a result of impaired mucociliary clearance and mucus impaction causing atelectasis and lobar collapse. Diagnosis is often delayed due to overlapping symptoms with other causes of neonatal respiratory distress. A work up for PCD should be initiated in the newborn with compatible clinical features, especially those with respiratory distress, consistent radiographic findings or persistent oxygen requirement and/or organ laterality defects.

Comparison of ciliary beat frequencies at different temperatures in young adults

Rationale

Direct visualisation of ciliary beat pattern (CBP) and ciliary beat frequency (CBF) has been recommended as the first-line diagnostic test in patients suspected of having primary ciliary dyskinesia (PCD). However, the test procedure is not yet completely standardised, and centres measure the CBF at different temperatures.

Objectives

It was the aim of the study to compare CBF at different temperatures, to establish normative values, to check for age dependency and to measure the temperature on the nasal mucosa of the participants.

Methods

High-speed video-microscopy analysis with a Sisson-Ammons Video Analysis (SAVA) system was used to determine CBP and CBF in the participants.

Measurements

Nasal brushings were taken and CBF was measured in randomised order at three temperatures: 25°C, 32°C and 37°C.

Main results

In total, 100 healthy young adults (74 female, 26 male), aged 20.2–31.9 years, were included in the study. We found a highly significant difference among the groups: the median CBF was 7.0 Hz at 25°C, 7.6 Hz at 32°C and 8.0 Hz at 37°C. The maximum time period ex vivo was 65 min and did not differ significantly. However, CBF was significantly higher when the cilia were kept at a higher temperature before the measurements were made. We found no correlation between CBF and the age of the participants. The median nasal mucosal temperature in our study participants was 30.2°C (range 24.7–35.8°C) comparable to the 30.2–34.4°C described in the literature.

Conclusions

The most appropriate temperature at which to measure CBF is 32°C. In our study, with 95% confidence for this temperature the CBF was between 6.3 and 9.0 Hz.

Equivalent to the nasal mucosa, the most appropriate temperature to measure ciliary beat frequency is 32°Chttps://bit.ly/2GCr2fP

PCD Detect: enhancing ciliary features through image averaging and classification

Primary ciliary dyskinesia (PCD) is an inherited disorder of the motile cilia. Early accurate diagnosis is important to help prevent lung damage in childhood and to preserve lung function. Confirmation of a diagnosis traditionally relied on assessment of ciliary ultrastructure by transmission electron microscopy (TEM); however, >50 known PCD genes have made the identification of biallelic mutations a viable alternative to confirm diagnosis. TEM and genotyping lack sensitivity, and research to improve accuracy of both is required. TEM can be challenging when a subtle or partial ciliary defect is present or affected cilia structures are difficult to identify due to poor contrast. Here, we demonstrate software to enhance TEM ciliary images and reduce background by averaging ciliary features. This includes an option to classify features into groups based on their appearance, to generate multiple averages when a nonhomogeneous abnormality is present. We validated this software on images taken from subjects with well-characterized PCD caused by variants in the outer dynein arm (ODA) heavy chain gene DNAH5. Examining more difficult to diagnose cases, we detected 1) regionally restricted absence of the ODAs away from the ciliary base, in a subject carrying mutations in DNAH9; 2) loss of the typically poorly contrasted inner dynein arms; and 3) sporadic absence of part of the central pair complex in subjects carrying mutations in HYDIN, including one case with an unverified genetic diagnosis. We show that this easy-to-use software can assist in detailing relationships between genotype and ultrastructural phenotype, improving diagnosis of PCD.

Access to medicines for rare diseases: beating the drum for primary ciliary dyskinesia

Rare diseases are collectively common, affecting an estimated 6.2% of the world's population [1], but each rare disease affects fewer than 4 to 5 in 10 000 individuals in Europe or less than 200 000 individuals in the USA [2]. Patients with rare diseases are often disadvantaged by late diagnosis and off-label prescribing of medicines [3]. Primary ciliary dyskinesia (PCD) is a genetic disease of impaired motile ciliary function that does not have a unique International Classification of Diseases (ICD)-10 code or licensed treatments, although Q34.8 denoting “other specified malformations of the respiratory tract” including nasopharyngeal atresia has also been applicable to PCD since 2017. The disease is characterised by mucus stagnation leading to chronic airway infection, bronchiectasis, chronic rhinosinusitis, reduced fertility and abnormalities of organ laterality with an associated increased risk of complex congenital heart disease [4]. The estimated prevalence of PCD in Europe is around 1 in 10 000 to 1 in 20 000 [5]. The international PCD cohort (iPCD) includes over 3800 PCD patients ranging in age from under 12 months to over 80 years, from Europe, Northern and Southern America, Australia and Western Asia [6]. Under-diagnosis of PCD is due to a lack of awareness among the general public and physicians in general, as well as a lack of diagnostic expertise in some countries [7]. Tools to help physicians identify patients needing testing (e.g. PICADAR) [8] and the European Respiratory Society (ERS) guidelines for diagnostic testing [9] aim to improve this. In contrast to cystic fibrosis (CF), a monogenic disease, PCD is caused by mutations in one of at least 45 identified genes for which there is no effective mutation-specific therapy; this is likely to be a long way off for most patients [10]. Thus, treatment aims to prevent and manage disease complications. Even then, the lack of an evidence base for supportive treatment in PCD means that treatment recommendations are based on expert opinion and extrapolated from CF despite differing pathophysiology [11].

Primary ciliary dyskinesia, a rare disease causing bronchiectasis, lacks a sound evidence base for treatment. @beatpcd proposes 1) forming a PCD European clinical trial network to address this situation and 2) conducting n-of-1 trials to access medication.https://bit.ly/3j5blfM

Motile ciliopathies

Motile cilia are highly complex hair-like organelles of epithelial cells lining the surface of various organ systems. Genetic mutations (usually with autosomal recessive inheritance) that impair ciliary beating cause a variety of motile ciliopathies, a heterogeneous group of rare disorders. The pathogenetic mechanisms, clinical symptoms and severity of the disease depend on the specific affected genes and the tissues in which they are expressed. Defects in the ependymal cilia can result in hydrocephalus, defects in the cilia in the fallopian tubes or in sperm flagella can cause female and male subfertility, respectively, and malfunctional motile monocilia of the left-right organizer during early embryonic development can lead to laterality defects such as situs inversus and heterotaxy. If mucociliary clearance in the respiratory epithelium is severely impaired, the disorder is referred to as primary ciliary dyskinesia, the most common motile ciliopathy. No single test can confirm a diagnosis of motile ciliopathy, which is based on a combination of tests including nasal nitric oxide measurement, transmission electron microscopy, immunofluorescence and genetic analyses, and high-speed video microscopy. With the exception of azithromycin, there is no evidence-based treatment for primary ciliary dyskinesia; therapies aim at relieving symptoms and reducing the effects of reduced ciliary motility.

Late Diagnosis of Infants with PCD and Neonatal Respiratory Distress

Neonatal respiratory distress (NRD) is common among infants with primary ciliary dyskinesia (PCD), but we do not know whether affected neonates receive a timely diagnosis. We used data from the international PCD cohort and assessed the proportion of patients with PCD who had a history of NRD and their age at diagnosis, stratifying by presence of laterality defects. First we analyzed data from all participants diagnosed after 2000, followed by individuals from a subgroup diagnosed using stricter criteria. Among the 1375 patients in the study, 45% had a history of NRD and 42% had laterality defects. Out of the 476 children with definite PCD diagnosis, 55% had a history of NRD and 50% had laterality defects. Overall, 30% of children with PCD were diagnosed during the first 12 months of life. This varied from 13% in those with situs solitus and no NRD, to 21% in those with situs solitus and NRD, 33% in those with situs anomalies but no NRD, and 52% in those with both situs anomalies and NRD. Our results suggest that we need to improve our knowledge of the neonatal presentation of infants with PCD and apply it so that these patients will receive appropriate care sooner.

Proceedings of the 4th BEAT-PCD Conference and 5th PCD Training School

Primary ciliary dyskinesia (PCD) is an inherited ciliopathy leading to chronic suppurative lung disease, chronic rhinosinusitis, middle ear disease, sub-fertility and situs abnormalities. As PCD is rare, it is important that scientists and clinicians foster international collaborations to share expertise in order to provide the best possible diagnostic and management strategies. 'Better Experimental Approaches to Treat Primary Ciliary Dyskinesia' (BEAT-PCD) is a multidisciplinary network funded by EU COST Action (BM1407) to coordinate innovative basic science and clinical research from across the world to drive advances in the field. The fourth and final BEAT-PCD Conference and fifth PCD Training School were held jointly in March 2019 in Poznan, Poland. The varied program of plenaries, workshops, break-out sessions, oral and poster presentations were aimed to enhance the knowledge and skills of delegates, whilst also providing a collaborative platform to exchange ideas. In this final BEAT-PCD conference we were able to build upon programmes developed throughout the lifetime of the COST Action. These proceedings report on the conference, highlighting some of the successes of the BEAT-PCD programme.

Registries and collaborative studies for primary ciliary dyskinesia in Europe

Primary ciliary dyskinesia (PCD) is a rare inherited disease characterised by malfunctioning cilia leading to a heterogeneous clinical phenotype with many organ systems affected. There is a lack of data on clinical presentation, prognosis and effectiveness of treatments, making it mandatory to improve the scientific evidence base.

This article reviews the data resources that are available in Europe for clinical and epidemiological research in PCD, namely established national PCD registries and national cohort studies, plus two large collaborative efforts (the international PCD (iPCD) Cohort and the International PCD Registry), and discusses their strengths, limitations and perspectives.

Denmark, Cyprus, Norway and Switzerland have national population-based registries, while England and France conduct multicentre cohort studies. Based on the data contained in these registries, the prevalence of diagnosed PCD is 3–7 per 100 000 in children and 0.2–6 per 100 000 in adults. All registries, together with other studies from Europe and beyond, contribute to the iPCD Cohort, a collaborative study including data from over 4000 PCD patients, and to the International PCD Registry, which is part of the ERN (European Reference Network)-LUNG network.

This rich resource of readily available, standardised and contemporaneous data will allow obtaining fast answers to emerging clinical and research questions in PCD.

The growing collaborative network of national and international registries and cohort studies of patients with PCD provides an excellent resource for research on this rare diseasehttps://bit.ly/3dto75l

Homozygous truncating NEK10 mutation, associated with primary ciliary dyskinesia: a case report

Background

Primary Ciliary Dyskinesia (PCD) is also known as immotile-cilia syndrome, an autosomal recessive disorder of ciliary function, leading to mucus retention in the respiratory system in childhood. Our knowledge in the pathophysiological aspect of this devastating disorder is increasing with the advancement of genetic and molecular testing.

Case presentation

Here in, we report two siblings with a classical clinical and radiological presentation of PCD. Using whole exome sequencing we identified a homozygous truncating variant (c.3402 T > A); p.(Tyr1134*) in the NEK10 gene. Western bolt analysis revealed a decrease in the expression of NEK10 protein in the patient cells.

Conclusions

NEK10 plays a central role in the post-mitotic process of cilia assembly, regulating ciliary length and functions during physiological and pathological status. This study highlights the challenges of identifying disease-causing variants for a highly heterogeneous disorder and reports on the identification of a novel variant in NEK10 which recently associated with PCD.

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.

Standardised follow-up of PCD patients enables quality research with real-time data from routine care, providing evidence for clinical decision-makinghttp://bit.ly/2PDfISF

Factors influencing harmonized health data collection, sharing and linkage in Denmark and Switzerland: A systematic review

Introduction

The digitalization of medicine has led to a considerable growth of heterogeneous health datasets, which could improve healthcare research if integrated into the clinical life cycle. This process requires, amongst other things, the harmonization of these datasets, which is a prerequisite to improve their quality, re-usability and interoperability. However, there is a wide range of factors that either hinder or favor the harmonized collection, sharing and linkage of health data.

Objective

This systematic review aims to identify barriers and facilitators to health data harmonization—including data sharing and linkage—by a comparative analysis of studies from Denmark and Switzerland.

Methods

Publications from PubMed, Web of Science, EMBASE and CINAHL involving cross-institutional or cross-border collection, sharing or linkage of health data from Denmark or Switzerland were searched to identify the reported barriers and facilitators to data harmonization.

Results

Of the 345 projects included, 240 were single-country and 105 were multinational studies. Regarding national projects, a Swiss study reported on average more barriers and facilitators than a Danish study. Barriers and facilitators of a technical nature were most frequently reported.

Conclusion

This systematic review gathered evidence from Denmark and Switzerland on barriers and facilitators concerning data harmonization, sharing and linkage. Barriers and facilitators were strictly interrelated with the national context where projects were carried out. Structural changes, such as legislation implemented at the national level, were mirrored in the projects. This underlines the impact of national strategies in the field of health data. Our findings also suggest that more openness and clarity in the reporting of both barriers and facilitators to data harmonization constitute a key element to promote the successful management of new projects using health data and the implementation of proper policies in this field. Our study findings are thus meaningful beyond these two countries.

Prevalence and course of disease after lung resection in primary ciliary dyskinesia: a cohort & nested case-control study

Background

Lung resection is a controversial and understudied therapeutic modality in Primary Ciliary Dyskinesia (PCD). We assessed the prevalence of lung resection in PCD across countries and compared disease course in lobectomised and non-lobectomised patients.

Methods

In the international iPCD cohort, we identified lobectomised and non-lobectomised age and sex-matched PCD patients and compared their characteristics, lung function and BMI cross-sectionally and longitudinally.

Results

Among 2896 patients in the iPCD cohort, 163 from 20 centers (15 countries) underwent lung resection (5.6%). Among adult patients, prevalence of lung resection was 8.9%, demonstrating wide variation among countries. Compared to the rest of the iPCD cohort, lobectomised patients were more often females, older at diagnosis, and more often had situs solitus. In about half of the cases (45.6%) lung resection was performed before presentation to specialized PCD centers for diagnostic work-up. Compared to controls (n = 197), lobectomised patients had lower FVC z-scores (− 2.41 vs − 1.35, p = 0.0001) and FEV1 z-scores (− 2.79 vs − 1.99, p = 0.003) at their first post-lung resection assessment. After surgery, lung function continued to decline at a faster rate in lobectomised patients compared to controls (FVC z-score slope: − 0.037/year Vs − 0.009/year, p = 0.047 and FEV1 z-score slope: − 0.052/year Vs − 0.033/year, p = 0.235), although difference did not reach statistical significance for FEV1. Within cases, females and patients with multiple lobe resections had lower lung function.

Conclusions

Prevalence of lung resection in PCD varies widely between countries, is often performed before PCD diagnosis and overall is more frequent in patients with delayed diagnosis. After lung resection, compared to controls most lobectomised patients have poorer and continuing decline of lung function despite lung resection. Further studies benefiting from prospective data collection are needed to confirm these findings.

Genetics of male infertility

Male infertility is a multifactorial pathological condition affecting approximately 7% of the male population. The genetic landscape of male infertility is highly complex as semen and testis histological phenotypes are extremely heterogeneous, and at least 2,000 genes are involved in spermatogenesis. The highest frequency of known genetic factors contributing to male infertility (25%) is in azoospermia, but the number of identified genetic anomalies in other semen and aetiological categories is constantly growing. Genetic screening is relevant for its diagnostic value, clinical decision making, and appropriate genetic counselling. Anomalies in sex chromosomes have major roles in severe spermatogenic impairment. Autosome-linked gene mutations are mainly involved in central hypogonadism, monomorphic teratozoospermia or asthenozoospermia, congenital obstructive azoospermia, and familial cases of quantitative spermatogenic disturbances. Results from whole-genome association studies suggest a marginal role for common variants as causative factors; however, some of these variants can be important for pharmacogenetic purposes. Results of studies on copy number variations (CNVs) demonstrate a considerably higher CNV load in infertile patients than in normozoospermic men, whereas whole-exome analysis has proved to be a highly successful diagnostic tool in familial cases of male infertility. Despite such efforts, the aetiology of infertility remains unknown in about 40% of patients, and the discovery of novel genetic factors in idiopathic infertility is a major challenge for the field of androgenetics. Large, international, and consortium-based whole-exome and whole-genome studies are the most promising approach for the discovery of the missing genetic aetiology of idiopathic male infertility.

Severe pulmonary disease in an adult primary ciliary dyskinesia population in Brazil

Primary Ciliary Dyskinesia (PCD) is underdiagnosed in Brazil. We enrolled patients from an adult service of Bronchiectasis over a two-year period in a cross-sectional study. The inclusion criteria were laterality disorders (LD), cough with recurrent infections and the exclusion of other causes of bronchiectasis. Patients underwent at least two of the following tests: nasal nitric oxide, ciliary movement and analysis of ciliary immunofluorescence, and genetic tests (31 PCD genes + CFTR gene). The clinical characterization included the PICADAR and bronchiectasis scores, pulmonary function, chronic Pseudomonas aeruginosa (cPA) colonization, exhaled breath condensate (EBC) and mucus rheology (MR). Forty-nine of the 500 patients were diagnosed with definite (42/49), probable (5/49), and clinical (2/49) PCD. Twenty-four patients (24/47) presented bi-allelic pathogenic variants in a total of 31 screened PCD genes. A PICADAR score > 5 was found in 37/49 patients, consanguinity in 27/49, LD in 28/49, and eight PCD sibling groups. FACED diagnosed 23/49 patients with moderate or severe bronchiectasis; FEV1 ≤ 50% in 25/49 patients, eight patients had undergone lung transplantation, four had been lobectomized and cPA+ was determined in 20/49. The EBC and MR were altered in all patients. This adult PCD population was characterized by consanguinity, severe lung impairment, genetic variability, altered EBC and MR.

Wide phenotypic variability in RSPH9-associated primary ciliary dyskinesia: review of a case-series from Cyprus

Background

Primary ciliary dyskinesia (PCD) is an inherited ciliary motility disorder caused by mutations in at least 40 genes. RSPH9 gene mutations encoding aberrant radial spoke head proteins have been linked with PCD. The clinical spectrum extent of RSPH9 gene mutations remains to date largely unknown. We aimed to describe the diagnostic and clinical phenotype in a case-series of RSPH9-associated PCD.

Methods

We performed whole exome sequencing in suspect patients from Cyprus who on repeated cilia biopsies demonstrated loss of the central pair apparatus on Transmission Electron Microscopy (TEM) and rotary beating patterns on High Speed Video Microscopy (HSVM), compatible to findings described previously in PCD patients bearing pathogenic RSPH9 mutations. In cases confirmed by genetic testing, we reviewed diagnostic, demographic and clinical data, as well as anthropometric and spirometric measurements.

Results

We diagnosed 7 individuals (5 females) homozygous for the novel RSPH9 splice site mutation c.670+2T>C in intron 4, who originated from two families. Despite bearing the same genetic variant, patients presented a highly variable age (median 47.9 years; range, 6.6 to 51.4 years) and with a diverse clinical picture, all reporting a history of chronic or recurrent wet cough (100%), and at varying frequencies neonatal respiratory distress (43%), chronic rhinosinusitis (71%), and wheezing (43%). Complications such as bronchiectasis (71%), history of pneumonia(s) (57%) and surgical interventions (43%) clustered in some patients displaying typical PCD, but not in others with milder phenotypes. BMI-z scores (median: 0.53; range, -0.69 to 1.52), FEV1-z scores (median: -0.37; range: -1.79 to 0.22) and FVC z-scores (median: -0.80; range: -2.01 to 0.36) were on average within the normal range, although slightly reduced.

Conclusions

In conclusion, RSPH9-associated PCD disease demonstrates wide phenotypic variability. In some cases, mild clinical presentation is difficult to justify diagnostic work-up, highlighting the importance of wider adoption of genetic diagnostics. Larger studies are needed to assess variability of clinical spectrum associated to alterations of PCD genes.

Primary ciliary dyskinesia among Arabs: Where do we go from here?

Primary ciliary dyskinesia (PCD), also known as immotile-cilia syndrome, is a rare genetic disease that is inherited in an autosomal recessive manner. Several studies have explored certain aspects of PCD in the Arab world, yet much is still lacking in terms of identifying the different characteristics of this disease. In this paper, we aim to briefly cover those studies published about PCD in Arab countries, as well as to provide recommendations and guidelines for future studies.

Pulmonary exacerbations in patients with primary ciliary dyskinesia: an expert consensus definition for use in clinical trials

Pulmonary exacerbations are a cause of significant morbidity in patients with primary ciliary dyskinesia (PCD) and are frequently used as an outcome measure in clinical research into chronic lung diseases. So far, there has been no consensus on the definition of pulmonary exacerbations in PCD.

30 multidisciplinary experts and patients developed a consensus definition for children and adults with PCD. Following a systematic review, the panel used a modified Delphi process with a combination of face-to-face meetings and e-surveys to develop a definition that can be used in research settings for children and adults with PCD.

A pulmonary exacerbation was defined by the presence of three or more of the following seven items: 1) increased cough, 2) change in sputum volume and/or colour, 3) increased shortness of breath perceived by the patient or parent, 4) decision to start or change antibiotic treatment because of perceived pulmonary symptoms, 5) malaise, tiredness, fatigue or lethargy, 6) new or increased haemoptysis, and 7) temperature >38°C.

The consensus panel proposed that the definition should be used for future clinical trials. The definition should be validated and the usability assessed during these studies.

A consensus definition for pulmonary exacerbations in children and adults with PCD for use in clinical trialshttp://ow.ly/Rcfr30n4Gn4

The Swiss Primary Ciliary Dyskinesia registry: objectives, methods and first results

Primary ciliary dyskinesia (PCD) is a rare, hereditary, multiorgan disease caused by defects in the structure and function of motile cilia. It results in a wide range of clinical manifestations, most commonly in the upper and lower airways. Central data collection in national and international registries is essential to studying the epidemiology of rare diseases and filling in gaps in knowledge of diseases such as PCD. For this reason, the Swiss Primary Ciliary Dyskinesia Registry (CH-PCD) was founded in 2013 as a collaborative project between epidemiologists and adult and paediatric pulmonologists. We describe the objectives and methodology of the CH-PCD, present initial results, and give an overview of current and ongoing projects. The registry records patients of any age, suffering from PCD, who are treated and resident in Switzerland. It collects information from patients identified through physicians, diagnostic facilities and patient organisations. The registry dataset contains data on diagnostic evaluations, lung function, microbiology and imaging, symptoms, treatments and hospitalisations. By May 2018, CH-PCD has contacted 566 physicians of different specialties and identified 134 patients with PCD. At present, this number represents an overall 1 in 63,000 prevalence of people diagnosed with PCD in Switzerland. Prevalence differs by age and region; it is highest in children and adults younger than 30 years, and in Espace Mittelland. The median age of patients in the registry is 25 years (range 5–73), and 41 patients have a definite PCD diagnosis based on recent international guidelines. Data from CH-PCD are contributed to international collaborative studies and the registry facilitates patient identification for nested studies. CH-PCD has proven to be a valuable research tool that already has highlighted weaknesses in PCD clinical practice in Switzerland. Trial registration number NCT03606200

Proceedings of the 3rd BEAT-PCD Conference and 4th PCD Training School

Primary ciliary dyskinesia (PCD) is a chronic suppurative airways disease that is usually recessively inherited and has marked clinical phenotypic heterogeneity. Classic symptoms include neonatal respiratory distress, chronic rhinitis since early childhood, chronic otitis media, recurrent airway infections leading to bronchiectasis, chronic sinusitis, laterality defects with and without congenital heart disease including abnormal situs in approximately 50% of the cases, and male infertility. Lung function deteriorates progressively from childhood throughout life. 'Better Experimental Approaches to Treat Primary Ciliary Dyskinesia' (BEAT-PCD) is a network of scientists and clinicians coordinating research from basic science through to clinical care with the intention of developing treatments and diagnostics that lead to improved long-term outcomes for patients. BEAT-PCD activities are supported by EU funded COST Action (BM1407). The third BEAT-PCD conference and fourth PCD training school were held jointly in February 2018 in Lisbon, Portugal. Presentations and workshops focussed on advancing the knowledge and skills relating to PCD in: basic science, epidemiology, diagnostic testing, clinical management and clinical trials. The multidisciplinary conference provided an interactive platform for exchanging ideas through a program of lectures, poster presentations, breakout sessions and workshops. Three working groups met to plan consensus statements. Progress with BEAT-PCD projects was shared and new collaborations were fostered. In this report, we summarize the meeting, highlighting developments made during the meeting.

The Swiss Paediatric Airway Cohort (SPAC)

Chronic respiratory symptoms, such as cough, wheeze and dyspnoea, are common in children; however, most research has, with the exception of a few large-scale clinical cohort studies, been performed in the general population or in small, highly-selected samples.

The Swiss Paediatric Airway Cohort (SPAC) is a national, prospective clinical cohort of children and adolescents who visit physicians for recurrent conditions, such as wheeze and cough, and exercise-related respiratory problems. The SPAC is an observational study and baseline assessment includes standardised questionnaires for families and data extracted from hospital records, including results of clinically indicated investigations, diagnoses and treatments. Outcomes are assessed through annual questionnaires, monthly symptom reporting via mobile phone and follow-up visits.

The SPAC will address important questions about clinical phenotypes, diagnosis, treatment, and the short- and long-term prognosis of common respiratory problems in children. The cohort currently consists of 347 patients from four major hospitals (Bern, Zurich, Basel and Lucerne), with 70–80 additional patients joining each month. More centres will join and the target sample size is a minimum of 3000 patients.

The SPAC will provide real-life data on children visiting the Swiss healthcare system for common respiratory problems and will provide a research platform for health services research and nested clinical and translational studies.

The Swiss Paediatric Airway Cohort (SPAC) is a unique research platform for common respiratory problems in childrenhttp://ow.ly/Y1v030lDnji

Bronchiectasis

Bronchiectasis refers to abnormal dilatation of the bronchi. Airway dilatation can lead to failure of mucus clearance and increased risk of infection. Pathophysiological mechanisms of bronchiectasis include persistent bacterial infections, dysregulated immune responses, impaired mucociliary clearance and airway obstruction. These mechanisms can interact and self-perpetuate, leading over time to impaired lung function. Patients commonly present with productive cough and recurrent chest infections, and the diagnosis of bronchiectasis is based on clinical symptoms and radiological findings. Bronchiectasis can be the result of several different underlying disorders, and identifying the aetiology is crucial to guide management. Treatment is directed at reducing the frequency of exacerbations, improving quality of life and preventing disease progression. Although no therapy is licensed for bronchiectasis by regulatory agencies, evidence supports the effectiveness of airway clearance techniques, antibiotics and mucolytic agents, such as inhaled isotonic or hypertonic saline, in some patients. Bronchiectasis is a disabling disease with an increasing prevalence and can affect individuals of any age. A major challenge is the application of emerging phenotyping and endotyping techniques to identify the patient populations who would most benefit from a specific treatment, with the goal of better targeting existing and emerging treatments and achieving better outcomes.

Lung function in patients with primary ciliary dyskinesia: an iPCD Cohort study

Primary ciliary dyskinesia (PCD) has been considered a relatively mild disease, especially compared to cystic fibrosis (CF), but studies on lung function in PCD patients have been few and small.This study compared lung function from spirometry of PCD patients to normal reference values and to published data from CF patients. We calculated z-scores and % predicted values for forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) using the Global Lung Function Initiative 2012 values for 991 patients from the international PCD Cohort. We then assessed associations with age, sex, country, diagnostic certainty, organ laterality, body mass index and age at diagnosis in linear regression models. Lung function in PCD patients was reduced compared to reference values in both sexes and all age groups. Children aged 6-9 years had the smallest impairment (FEV₁ z-score -0.84 (-1.03 to -0.65), FVC z-score -0.31 (-0.51 to -0.11)). Compared to CF patients, FEV₁ was similarly reduced in children (age 6-9 years PCD 91% (88-93%); CF 90% (88-91%)), but less impaired in young adults (age 18-21 years PCD 79% (76-82%); CF 66% (65-68%)). The results suggest that PCD affects lung function from early in life, which emphasises the importance of early standardised care for all patients.

Why, when and how to investigate primary ciliary dyskinesia in adult patients with bronchiectasis

Bronchiectasis represents the final pathway of several infectious, genetic, immunologic or allergic disorders. Accurate and prompt identification of the underlying cause is a key recommendation of several international guidelines, in order to tailor treatment appropriately. Primary ciliary dyskinesia (PCD) is a genetic cause of bronchiectasis in which failure of motile cilia leads to poor mucociliary clearance. Due to poor ciliary function in other organs, individuals can suffer from chronic rhinosinusitis, otitis media and infertility. This paper explores the current literature describing why, when and how to investigate PCD in adult patients with bronchiectasis. We describe the main PCD diagnostic tests and compare the two international PCD diagnostic guidelines. The expensive multi-test diagnostic approach requiring a high level of expertise and specialist equipment, make the multifaceted PCD diagnostic pathway complex. Therefore, the risk of late or missed diagnosis is high and has clinical and research implications. Defining the number of patients with bronchiectasis due to PCD is complex. To date, few studies outlining the aetiology of adult patients with bronchiectasis conduct screening tests for PCD, but they do differ in their diagnostic approach. Comparison of these studies reveals an estimated PCD prevalence of 1-13% in adults with bronchiectasis and describe patients as younger than their counterparts with moderate impairment of lung function and higher rates of chronic infection with Pseudomonas aeruginosa. Diagnosing PCD has clinical, socioeconomic and psychological implications, which affect patients' life, including the possibility to have a specific and multidisciplinary team approach in a PCD referral centre, as well as a genetic and fertility counselling and special legal aspects in some countries. To date no specific treatments for PCD have been approved, standardized diagnostic protocols for PCD and recent diagnostic guidelines will be helpful to accurately define a population on which planning RCT studies to evaluate efficacy, safety and accuracy of PCD specific treatments.

The Italian registry of pulmonary non-tuberculous mycobacteria - IRENE: the study protocol

Background

A substantial increase in pulmonary and extra-pulmonary diseases due to non-tuberculous mycobacteria (NTM) has been documented worldwide, especially among subjects suffering from chronic respiratory diseases and immunocompromised patients. Many questions remain regarding the epidemiology of pulmonary disease due to NTM (NTM-PD) mainly because reporting of NTM-PD to health authorities is not mandated in several countries, including Italy. This manuscript describes the protocol of the first Italian registry of adult patients with respiratory infections caused by NTM (IRENE).

Methods

IRENE is an observational, multicenter, prospective, cohort study enrolling consecutive adult patients with either a NTM respiratory isolate or those with NTM-PD. A total of 41 centers, including mainly pulmonary and infectious disease departments, joined the registry so far. Adult patients with all of the following are included in the registry: 1) at least one positive culture for any NTM species from any respiratory sample; 2) at least one positive culture for NTM isolated in the year prior the enrolment and/or prescribed NTM treatment in the year prior the enrolment; 3) given consent to inclusion in the study. No exclusion criteria are applied to the study. Patients are managed according to standard operating procedures implemented in each IRENE clinical center. An online case report form has been developed to collect patients’ demographics, comorbidities, microbiological, laboratory, functional, radiological, clinical, treatment and outcome data at baseline and on an annual basis. An IRENE biobank has also been developed within the network and linked to the clinical data of the registry.

Conclusions

IRENE has been developed to inform the clinical and scientific community on the current management of adult patients with NTM respiratory infections in Italy and acts as a national network to increase the disease’s awareness.

Trial registration

Clinicaltrial.gov: NCT03339063.

Motile Ciliary Disorders in Chronic Airway Inflammatory Diseases: Critical Target for Interventions

PURPOSE OF REVIEW

Impaired mucociliary clearance has been implicated in chronic upper and lower airway inflammatory diseases (i.e., allergic and non-allergic rhinitis, chronic rhinosinusitis with or without nasal polyps and asthma). How motile ciliary disorders (impaired ciliogenesis, ciliary beating and ultrastructural defects) are implicated in chronic airway inflammatory diseases is not fully understood. Elaboration of the role of motile ciliary disorders may serve as therapeutic targets for improving mucociliary clearance, thereby complementing contemporary disease management.

RECENT FINDINGS

We have summarized the manifestations of motile ciliary disorders and addressed the underlying associations with chronic airway inflammatory diseases. A panel of established and novel diagnostic tests and therapeutic interventions are outlined. Physicians should be vigilant in screening for motile ciliary disorders, particularly in patients with co-existing upper and lower airway inflammatory diseases. Proper assessment and treatment of motile ciliary disorders may have added value to the management and prevention of chronic airway inflammatory diseases.

Diagnostic yield of a targeted gene panel in primary ciliary dyskinesia patients

We aimed to determine the diagnostic yield of a targeted-exome panel in a cohort of 74 Dutch primary ciliary dyskinesia (PCD) patients. The panel consisted of 26 PCD-related and 284 candidate genes. To prioritize PCD candidate genes, we investigated the transcriptome of human airway cells of 12 healthy volunteers during in vitro ciliogenesis and hypothesized that PCD-related genes show significant upregulation. We compared gene expression in epithelial precursor cells grown as collagen monolayer and ciliated cells grown in suspension by RNA sequencing. All genes reported as PCD causative, except NME8, showed significant upregulation during in vitro ciliogenesis. We observed 67.6% diagnostic yield when testing the targeted-exome panel in our cohort. There was relatively high percentage of DNAI and HYDIN mutations compared to other countries. The latter may be due to our solution for the problem of the confounding HYDIN2 pseudogene. Candidate genes included two recently published PCD-related genes DNAJB13 and PIH1D3; identification of the latter was a direct result of this study. In conclusion, we demonstrate 67.6% diagnostic yield by targeted exome sequencing in a Dutch PCD population and present a highly sensitive and moderately specific approach for identification of PCD-related genes, based on significant upregulation during in vitro ciliogenesis.

Proceedings of the 2nd BEAT-PCD conference and 3rd PCD training school: part 1

Primary ciliary dyskinesia (PCD) is a rare heterogenous condition that causes progressive suppurative lung disease, chronic rhinosinusitis, chronic otitis media, infertility and abnormal situs. 'Better Experimental Approaches to Treat Primary Ciliary Dyskinesia' (BEAT-PCD) is a network of scientists and clinicians coordinating research from basic science through to clinical care with the intention of developing treatments and diagnostics that lead to improved long-term outcomes for patients. BEAT-PCD activities are supported by EU funded COST Action (BM1407). The second BEAT-PCD conference, and third PCD training school were held jointly in April 2017 in Valencia, Spain. Presentations and workshops focussed on advancing the knowledge and skills relating to PCD in: basic science, epidemiology, diagnostic testing, clinical management and clinical trials. The multidisciplinary conference provided an interactive platform for exchanging ideas through a program of lectures, poster presentations, breakout sessions and workshops. Three working groups met to plan consensus statements. Progress with BEAT-PCD projects was shared and new collaborations were fostered. In this report, we summarize the meeting, highlighting developments made during the meeting.

Seeing cilia: imaging modalities for ciliary motion and clinical connections

The respiratory tract is lined with multiciliated epithelial cells that function to move mucus and trapped particles via the mucociliary transport apparatus. Genetic and acquired ciliopathies result in diminished mucociliary clearance, contributing to disease pathogenesis. Recent innovations in imaging technology have advanced our understanding of ciliary motion in health and disease states. Application of imaging modalities including transmission electron microscopy, high-speed video microscopy, and micron-optical coherence tomography could improve diagnostics and be applied for precision medicine. In this review, we provide an overview of ciliary motion, imaging modalities, and ciliopathic diseases of the respiratory system including primary ciliary dyskinesia, cystic fibrosis, chronic obstructive pulmonary disease, and idiopathic pulmonary fibrosis.

Growth and nutritional status, and their association with lung function: a study from the international Primary Ciliary Dyskinesia Cohort

Chronic respiratory disease can affect growth and nutrition, which can influence lung function. We investigated height, body mass index (BMI), and lung function in patients with primary ciliary dyskinesia (PCD).In this study, based on the international PCD (iPCD) Cohort, we calculated z-scores for height and BMI using World Health Organization (WHO) and national growth references, and assessed associations with age, sex, country, diagnostic certainty, age at diagnosis, organ laterality and lung function in multilevel regression models that accounted for repeated measurements.We analysed 6402 measurements from 1609 iPCD Cohort patients. Height was reduced compared to WHO (z-score -0.12, 95% CI -0.17 to -0.06) and national references (z-score -0.27, 95% CI -0.33 to -0.21) in male and female patients in all age groups, with variation between countries. Height and BMI were higher in patients diagnosed earlier in life (p=0.026 and p<0.001, respectively) and closely associated with forced expiratory volume in 1 s and forced vital capacity z-scores (p<0.001).Our study indicates that both growth and nutrition are affected adversely in PCD patients from early life and are both strongly associated with lung function. If supported by longitudinal studies, these findings suggest that early diagnosis with multidisciplinary management and nutritional advice could improve growth and delay disease progression and lung function impairment in PCD.

Secondary defects detected by transmission electron microscopy in primary ciliary dyskinesia diagnostics

Primary ciliary dyskinesia (PCD) is predominantly an autosomal recessively inherited condition that affects ~1 in 15,000 people. Diagnosis of PCD can be complex and is ordinarily based on the results of multiple investigations. These investigations include nasal nitric oxide, high-speed video microscopy, genotyping, and electron microscopy analysis of ciliary ultrastructure. A diagnosis is ultimately confirmed by the presence of a hallmark defect identified by transmission electron microscopy or biallelic variants in a known PCD gene. Secondary ciliary defects are commonly seen in samples submitted for diagnosis of PCD. Acquired secondary ciliary ultrastructural abnormalities, which are not caused by a variant in a ciliary gene, are usually transient and reversible however failure to separate primary versus secondary defects can lead to misdiagnosis. In this review, we describe causes of secondary ciliary defects, identify the ultrastructural appearances associated with secondary ciliary dyskinesia and finally suggest methods to avoid misdiagnosis of PCD due to these acquired ciliary defects.