Primary ciliary dyskinesia: current state of the art

Primary ciliary dyskinesia: An update on contemporary diagnosis

KEY POINTS

Primary ciliary dyskinesia (PCD) is a complex diagnosis without a universal diagnostic test Clinicians must have some skepticism of historic diagnoses of PCD Clinicians should consider a diagnosis of PCD in patients with recalcitrant disease.

Bronchodilator responsiveness in children with primary ciliary dyskinesia

Background

Reversible airway obstruction is common in children with primary ciliary dyskinesia. However, the diagnostic value of adding bronchodilator (BD) response testing to routine spirometry is unclear.

Methods

This is a retrospective analysis of pulmonary function test results obtained from children with primary ciliary dyskinesia seen as outpatients at the Hospital for Sick Children, Toronto. Spirometry results were collected for every appointment with BD response testing ("Visit", with pre-BD and post-BD measurements) as well as for the previous ("Baseline") and following ("Follow-up") encounters.

Results

A positive BD response was seen in 86 out of 474 (18.1%) of the pulmonary function tests from 82 children with primary ciliary dyskinesia. BD responsiveness was associated with a significant absolute change (±sd) in % predicted forced expiratory volume in 1 s (FEV1) from Baseline to Visit pre-BD (-6.5±10.3%, p<0.001), but not from Baseline to Follow-up (0.4±10.8, p=0.757). Antimicrobial therapy was initiated more commonly following a Visit with a positive BD response (OR 3.8, 95% CI 2.2-6.6) compared to no BD response. Children with a positive BD response had a greater annual decline in FEV1 % predicted compared to those with no BD response (-0.9% per year versus -0.5% per year, p<0.001). The annual decline in FEV1 % predicted was greater in children with multiple compared to one measured positive BD responses (-1.3% per year versus -0.6% per year, p<0.001) and in those not treated with antibiotic therapy following a positive BD response compared to those treated with antibiotics (-1.1% versus -0.6%, p<0.001).

Conclusion

A positive BD response in children with primary ciliary dyskinesia may help identify those at risk for accelerated lung disease progression.

The First Case of a Homozygous CCNO NM 021147.4 Mutation Associated With Primary Ciliary Dyskinesia in Two Indian Siblings

Primary ciliary dyskinesia (PCD) is a heterogeneous autosomal recessive disease marked by organ lateralization in 50% of patients, chronic sinopulmonary disease, infertility in men, and neonatal respiratory distress. Respiratory control cells contain CCNO in their apical cytoplasm, which is necessary for the development of multiciliate cells, basal body amplification, and migration. Reduced generation of multiple motile cilia, a rare form of PCD, has been linked to CCNO gene abnormalities. Individuals with CCNO mutations have been reported to suffer from severe lower respiratory infections that cause progressive impairment of lung function. For the first time, we describe the CCNO NM 021147.4 (c.258 262dup.p, Gln88argfs*8 Homozygous) gene mutation in an Indian consanguineous family that resulted in severe PCD.

Dual-allele heterozygous mutation of DNAH5 gene in a boy with primary ciliary dyskinesia: A case report

RATIONALE

To analyze clinical and imaging features, ciliary structure and family gene mutation loci of a primary ciliary dyskinesia (PCD) boy with a dual-allele heterozygous mutation of DNAH5.

PATIENT CONCERNS

Clinical data of the proband and relatives. Electronic bronchoscopy, transmission electron microscope (TEM) of the cilia and next-generation sequencing (NGS) were performed. PCD-related DNAH5 exon mutation sites were searched.

DIAGNOSES

A 10-year and 10-month-old boy was hospitalized due to "recurrent cough, expectoration, sputum and shortness of breathing after activity for over 7 years, and aggravated for 1 week." Moderate and fine wet rales were detected in bilateral lungs. Clubbing fingers and toes were observed. In local hospitals, he was diagnosed with Mycoplasma pneumoniae infection and Streptococcus pneumoniae was cultured.

INTERVENTIONS

Pulmonary function testing showed mixed ventilation dysfunction and positive for bronchial dilation test. Imaging examination and fiberoptic bronchoscopy revealed transposition of all viscera, bilateral pneumonia, and bronchiectasis. TEM detected no loss of the outer dynein arms. NGS identified 2 mutations (c.4360C>T, c.9346C>T) in the DNAH5 gene inherited from healthy parents.

OUTCOMES

According to literature review until 2022, among 144 exon gene mutations causing amino acid changes, C>T mutation is the most common in 44 cases, followed by deletion mutations in 30 cases. Among the amino acid changes induced by gene mutation, terminated mutations were identified in 89 cases.

LESSONS

For suspected PCD patients, TEM and NGS should be performed. Prompt diagnosis and treatment may delay the incidence of bronchiectasis and improve clinical prognosis.

Ear and upper airway clinical outcome measures for use in primary ciliary dyskinesia research: a scoping review

BACKGROUND

Primary ciliary dyskinesia (PCD) is a rare genetic disorder characterised by pulmonary, otological and sino-nasal manifestations. Well-defined clinical outcome measures are needed in such rare diseases research to improve follow-up and treatments. Pulmonary outcome measures have recently been described. The aim of this study was to identify ear and upper airway outcome measures that could be used for longitudinal follow-up of individuals with PCD.

METHODS

A scoping review was performed by systematically searching MEDLINE, Embase and Cochrane Database of Systematic Reviews online databases for studies published from January 1996 to March 2022 that included at least 10 adult or paediatric PCD patients and reported ear and upper airway outcomes.

RESULTS

33 studies (1794 patients) were included. 10 ear and upper airway outcomes were reported. 17 studies reported audiometry, 16 reported otoscopic findings, and 13 reported rhinoscopic findings and sinus imaging. Health-related quality of life questionnaires were performed in seven studies. There was a high variability in definitions and measurement of outcomes between studies.

CONCLUSIONS

This scoping review highlights the lack of data regarding ear and upper airway outcomes in PCD. It also reports a high heterogeneity in outcome definitions or measures. We provide well-founded specific suggestions to standardise ear and upper airway outcome definitions and reporting for future PCD research studies.

Novel Pathogenic DNAH5 Variants in Primary Ciliary Dyskinesia: Association with Visceral Heterotaxia and Neonatal Cholestasis

The dynein axonemal heavy chain 5 gene codes for a subunit of axonemal dynein necessary for ciliary motor function. Though research has elucidated the consequences of some variants in this gene, it is still unclear whether many variants in the DNAH5 locus are benign or pathogenic due to the rarity of primary ciliary dyskinesia (PCD, of which Kartagener's syndrome is a subset). Here, we introduce the case of an infant boy presenting with the classical findings of PCD along with visceral heterotaxia and neonatal cholestasis. Genetic testing indicated that the patient is a compound heterozygote with a pathogenic c.8498G > A (known as pathogenic) on the maternally derived allele and two variants of uncertain significance, c.1206T > A and c.7800T > G, on the paternally derived allele. As PCD is autosomal recessive, we conclude that one, or both, of these paternally derived variants are pathogenic. To our knowledge, this is the first time that the clinical implications of c.1206T > A (p.Asn402Lys) and c.7800T > G (p.Ile2600Met) are documented. Furthermore, we use this case as an example to recommend clinicians to assess for PCD and laterality defects when presented with severe infantile cholestasis. While the association of cholestasis with PCD is relatively uncommon, PCD is a risk factor for increased prevalence of biliary atresia and infections, both of which are known causes of cholestasis in early infancy.

Rediscovering Primary Cilia in Pancreatic Islets

Primary cilia are microtubule-based sensory and signaling organelles on the surfaces of most eukaryotic cells. Despite their early description by microscopy studies, islet cilia had not been examined in the functional context until recent decades. In pancreatic islets as in other tissues, primary cilia facilitate crucial developmental and signaling pathways in response to extracellular stimuli. Many human developmental and genetic disorders are associated with ciliary dysfunction, some manifesting as obesity and diabetes. Understanding the basis for metabolic diseases in human ciliopathies has been aided by close examination of cilia action in pancreatic islets at cellular and molecular levels. In this article, we review the evidence for ciliary expression on islet cells, known roles of cilia in pancreas development and islet hormone secretion, and summarize metabolic manifestations of human ciliopathy syndromes. We discuss emerging data on primary cilia regulation of islet cell signaling and the structural basis of cilia-mediated cell crosstalk, and offer our interpretation on the role of cilia in glucose homeostasis and human diseases.

Siewert-Kartagener's syndrome in a dog

Siewert-Kartagener's syndrome, a type of primary ciliary dyskinesia, is a complex disease comprising situs inversus, rhinosinusitis, and bronchiectasis. Situs inversus totalis is a condition in which all organs in the thoracic and abdominal cavities are reversed. Furthermore, primary ciliary dyskinesia, an autosomal genetic disease, may coexist with situs inversus totalis. Reports on Siewert-Kartagener's syndrome in veterinary medicine are limited. We report a rare case of primary ciliary dyskinesia with Siewert-Kartagener's syndrome in a dog, concurrently infected with canine distemper virus and type-2 adenovirus. This case highlights that situs inversus totalis can cause primary ciliary dyskinesia, and concurrent infections are possible.

Prevalence and founder effect of DRC1 exon 1-4 deletion in Korean patients with primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a genetically heterogeneous disorder affecting ciliary structure and function. PCD exhibiting dynein regulatory complex subunit 1 (DRC1) exon 1-4 deletion has been reported in several Japanese PCD patients; however, no large scale studies have been performed. Here, we aimed to determine the prevalence and founder effect of this variant in the Korean population. Using an in-house copy number variation tool, we screened for DRC1 exon 1-4 deletion in 20 patients with PCD and exome data of 1435 patients in the Seoul National University Hospital repository. In cases of suspected DRC1 deletion, confirmatory gap-PCR was performed. In a PCD cohort, three of 20 (15%) patients were positive for DRC1 exon 1-4 deletion (NM_145038.5(DRC1): c.1-3952_540 + 1331del27748-bp) while pathogenic variants were found in CCDC39 (N = 1), DNAAF6 (N = 1), DNAH9 (N = 1). In the 1,435-sample exome data, seven patients (0.49%) were confirmed to have DRC1 exon 1-4 deletion. A chimeric sequence including the junction was searched from the 1000 Genomes Project data repository. One Japanese patient (0.96%) was found to have the same DRC1 exon 1-4 deletion, which was absent in other populations. This study demonstrated that the DRC1 exon 1-4 deletion is a founder mutation based on haplotype analysis. In summary, the prevalence of PCD based on DRC1 exon 1-4 deletion is particularly high in Korean and Japanese populations, which is attributed to the founder effect. Genetic testing for DRC1 exon 1-4 deletion should be considered as an initial screening tool for Korean and Japanese patients with PCD.

Lung Function in Children with Primary Ciliary Dyskinesia

BACKGROUND

Primary ciliary dyskinesia (PCD) is characterized by impaired mucociliary clearance that results in accumulation of mucus and bacteria in the airways. Lower respiratory tract infections lead to airway remodeling and lung function impairment. The aim of our narrative review is to discuss available data on lung function in PCD children, focusing on risk factors for lung function impairment.

METHODS

Relevant published studies searching MEDLINE/Pubmed are included in this narrative review, using these terms: "primary ciliary dyskinesia" and "pulmonary function test" or "spirometry" or "lung function". Filters were language (English) and age of study subjects (0-18 years).

RESULTS AND CONCLUSIONS

The majority of recent published studies showed normal spirometric values in PCD children, even if some authors described a pulmonary impairment. Together with spirometry, Lung Clearance Index has been applied for detecting peripheral airway disease, and it might have a role in early mild lung disease assessment. Studies on lung function trajectories after PCD diagnosis showed a significant heterogeneity, with some patients maintaining reasonably good lung function, whereas others showing a decline. Further studies are needed to analyze lung function prospectively from childhood into adulthood, and to evaluate whether lung function trajectories are affected by PCD clinical phenotype, ultrastructural ciliary defect or genetic background.

In vitro measurement of ciliary beat frequency in 92 children with recurrent respiratory tract problems

Background

Chronic or recurrent mucoid respiratory tract symptoms may be difficult to diagnose.

Method

Ninety-two children with chronic respiratory symptoms were divided into 4 groups: 18 children with refractory asthma, 10 with bronchiectasis without dextrocardia, 18 with dextrocardia and 46 with recurrent respiratory tract infections. Except for five neonates, cytology samples were taken under general anaesthesia. Ciliary beat frequency was measured photometrically and analysed by in-house computer software.

Results

Nasal polyps were found in one child with normal ciliary beat frequency. Twenty-six children had no beating cilia (male to female ratio, 15:11). The effect of increasing temperature on the ciliary beat frequency of the remaining 66 patients was evaluated (42 patients, more than 30°C, median, 8.3 Hz; 24 patients, 30–37°C, median, 11.8 Hz; p = 0.0003).

Conclusion

The measurement of ciliary beat frequency is part of the diagnostic work up of patients with persistent or recurrent respiratory tract infections.

Pathogenic variants identified using whole-exome sequencing in Chinese patients with primary ciliary dyskinesia

The genetic factors contributing to primary ciliary dyskinesia (PCD), a rare autosomal recessive disorder, remain elusive for ~20%-35% of patients with complex and abnormal clinical phenotypes. Our study aimed to identify causative variants of PCD-associated pathogenic candidate genes using whole-exome sequencing (WES). All patients were diagnosed with PCD based on clinical phenotype or transmission electron microscopy images of cilia. WES and bioinformatic analysis were then conducted on patients with PCD. Identified candidate variants were validated by Sanger sequencing. Pathogenicity of candidate variants was then evaluated using in silico software and the American College of Medical Genetics and Genomics (ACMG) database. In total, 13 rare variants were identified in patients with PCD, among which were three homozygous causative variants (including one splicing variant) in the PCD-associated genes CCDC40 and DNAI1. Moreover, two stop-gain heterozygous variants of DNAAF3 and DNAH1 were classified as pathogenic variants based on the ACMG criteria. This study identified novel potential pathogenic genetic factors associated with PCD. Noteworthy, the patients with PCD carried multiple rare causative gene variants, thereby suggesting that known causative genes along with other functional genes should be considered for such heterogeneous genetic disorders.

CCNO mutation as a cause of primary ciliary dyskinesia: A case report

BACKGROUND

Primary ciliary dyskinesia (PCD) is an uncommon and genetically diverse condition. According to reports, most patients had more than 50 visits before being diagnosed with PCD, and the age at diagnosis was mostly in preschool, with an average age of about (10.9 ± 14.4) years old. CCNO is a pathogenic gene that regulates the cell cycle, and its mutation is linked to the uncommon human genetic disorder PCD. Although the prevalence of the CCNO mutation is regarded to be exceptionally low, new reports of this mutation have increased in comparison to prior ones. PCD patients with CCNO are rare, and the incidence rate is no more than 2% in whole PCD patients.

CASE SUMMARY

Here, we report a case of a young Chinese woman diagnosed with PCD, who was found to carry the CCNO gene by whole exon gene sequencing. In this case, a young non-smoking Chinese female exhibiting recurrent cough and sputum at birth. Chest computed tomography (CT) showed bronchiectasis with infection, and sinus CT showed chronic sinusitis. However, the patient had no visceral transposition and no history of infertility. Under electron microscope, it was found that cilia were short and reduced in number, and no power arm of cilia was observed. Whole exon sequencing analysis of the genome of the patient showed that the patient carried CCNO pathogenic gene, exon c.303C>A nonsense mutation and c.248_252dup frameshift mutation. Her clinical symptoms and CT images were improved after two months of treatment with aerosol inhalation and oral azithromycin.

CONCLUSION

The results showed that CCNO is an important cause of PCD. More mutant genes that may contribute to genetically diverse disorders like PCD have been discovered as sequencing technology has advanced. Furthermore, the increase of genetic information makes it easier to diagnose uncommon diseases in clinical practice.

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.

Engineering rotating apical-out airway organoid for assessing respiratory cilia motility

Motile cilia project from the airway apical surface and directly interface with inhaled external environment. Owing to cilia's nanoscale dimension and high beating frequency, quantitative assessment of their motility remains a sophisticated task. Here we described a robust approach for reproducible engineering of apical-out airway organoid (AOAO) from a defined number of cells. Propelled by exterior-facing cilia beating, the mature AOAO exhibited stable rotational motion when surrounded by Matrigel. We developed a computational framework leveraging computer vision algorithms to quantify AOAO rotation and correlated it with the direct measurement of cilia motility. We further established the feasibility of using AOAO rotation to recapitulate and measure defective cilia motility caused by chemotherapy-induced toxicity and by CCDC39 mutations in cells from patients with primary ciliary dyskinesia. We expect our rotating AOAO model and the associated computational pipeline to offer a generalizable framework to expedite the modeling of and therapeutic development for genetic and environmental ciliopathies.

Novel Gene Variants Associated with Primary Ciliary Dyskinesia

OBJECTIVES

To determine the demographic, clinical, and genetic profile of Turkish Caucasian PCD cases.

METHODS

Targeted next-generation sequencing (t-NGS) of 46 nuclear genes was performed in 21 unrelated PCD cases. Sanger sequencing confirmed of potentially disease-related variations, and genotype-phenotype correlations were evaluated.

RESULTS

Disease-related variations were identified in eight different genes (CCDC39, CCDC40, CCDC151, DNAAF2, DNAAF4, DNAH11, HYDIN, RSPH4A) in 52.4% (11/21) of the cases. The frequency of variations for CCDC151, DNAH11, and DNAAF2 genes which were highly mutated genes in the cohort was 18% in 11 patients. Each of the remaining gene variations was detected once (9%) in different patients. The variants, p.R482fs*12 in CCDC151, p.E216* in DNAAF2, p.I317* in DNAAF4, p.L318P and p.R1865* in DNAH11, and p.N1505D and p.L1167P in HYDIN gene were identified as novel variations. Interestingly, varying phenotypic findings were identified even in patients with the same mutation, which once again confirmed that PCD has a high phenotypic heterogeneity and shows individual differences.

CONCLUSION

This t-NGS panel is potentially helpful for exact and rapid identification of reported/novel PCD-disease-causing variants to establish the molecular diagnosis of ciliary diseases.

Primary Ciliary Dyskinesia: A Rare and Often Underdiagnosed Disease

Primary ciliary dyskinesia (PCD) is a rare autosomal recessive disease with clinical features of ear, sinus, and pulmonary infections that overlap with common respiratory illnesses of childhood. It is a progressive disorder that has significant influence on quality of life, lung function, and survival. Given the considerable overlap of symptoms between common illnesses and PCD, a high index of suspicion by primary care providers is needed to consider the diagnosis. There is not a single "gold standard" diagnostic test for PCD and multiple diagnostic methods coupled with specialized expertise is often needed to make the diagnosis. Patients with PCD also have comorbidities requiring a multidisciplinary approach for optimal clinical management. It is important for primary care physicians to recognize the PCD clinical phenotype and have a diagnostic framework for these patients. [Pediatr Ann. 2022;51(2):e82-e85.].

Novel compound heterozygous CCDC40 mutations in a familial case of primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a rare genetic disorder characterized by motile ciliary dysfunction and impaired ultrastructure. Despite numerous studies, the genetic basis for about 30% of PCD cases remains to be elucidated. Here, we present the identification and functional analysis of two novel mutations in the gene encoding coiled-coil domain-containing protein 40 (CCDC40), which are found in a familial case of PCD. These novel CCDC40 mutations, NM_017950.4: c.2236-2delA and c.2042_2046delTCACA, NP_060420.2: p.(Ile681fs), were identified by whole-exome sequencing (WES). Sanger sequencing was then performed to confirm the WES results and determine the CCDC40 gene sequences of the proband's parents. The c.2042_2046delTCACA mutation disrupts the reading frame of the protein and is therefore predicted to produce a non-functional protein. Using a minigene assay with the pcDNA3.1(+) plasmid, we further investigated the potential pathogenic effects of the c.2236-2delA mutation and found that this mutation leads to formation of a truncated protein via splicing disruption. Thus, in summary, we identified two mutations of the CCDC40 gene that can be considered pathogenic compound heterozygous mutations in a case of familial PCD, thereby expanding the known mutational spectrum of the CCDC40 gene in this disease.

Clinical and molecular characteristics of primary ciliary dyskinesia: A tertiary care centre experience

BACKGROUND

Primary ciliary dyskinesia (PCD) is a ciliopathy with diverse clinical and genetic findings caused by abnormal motile cilia structure and function. In this study, we describe the clinical characteristics of confirmed PCD cases in our population and report the radiological, genetic, and laboratory findings.

METHODS

This was a retrospective, observational, single-centre study. We enrolled 18 patients who were diagnosed with confirmed PCD between 2015 and 2019. We then analyzed their data, including clinical findings and workup.

RESULTS

In our cohort, 56% of patients had molecularly confirmed PCD, and RSPH9 was the most common gene identified. Transmission electron microscopy (TEM) showed an ultrastructural defect in 64% of samples, all of which matched the genetic background of the patient. Situs inversus (SI) was observed in 50% of patients, and congenital heart disease was observed in 33%. The median body mass index (BMI) was 15.87 kg/m², with a median z score of -1.48. The median FEV1 value was 67.6% (z score - 2.43). Radiologically, bronchiectasis was noted in 81% of patients at a variable degree of severity. Lung bases were involved in 91% of patients. We were unable to correlate the genotype-phenotype findings.

CONCLUSION

We describe the clinical and molecular characteristics of patients with confirmed PCD in a tertiary centre in Saudi Arabia and report 9 new pathogenic or likely pathogenic variants in one of the PCD-associated genes.

Novel compound heterozygous mutations of DNAH5 identified in a pediatric patient with Kartagener syndrome: case report and literature review

BACKGROUND

Kartagener syndrome is a subtype of primary ciliary dyskinesia that may exhibit various symptoms including neonatal respiratory distress and frequent infections of the lung, sinus and middle ear because of the impaired function of motile cilia. In addition to typical symptoms of primary ciliary dyskinesia, patients with Kartagener syndrome also show situs inversus. It is an autosomal recessive disorder which is mostly caused by mutations in DNAH5. Kartagener syndrome is often underdiagnosed due to challenges in the diagnosis process. As next-generation sequencing becomes widely used in clinical laboratories, genetic testing provides an accurate approach to the diagnosis of Kartagener syndrome.

CASE PRESENTATION

A 7-year-old female patient presented with runny nose of 6 years duration and recurrent cough with phlegm of 2 years duration. Kartagener syndrome was diagnosed through diagnostic tests such as nasal nitric oxide (NO) concentration and transmission electron microscopy, and after performing other exams that corroborated the diagnosis, such as computed tomography, bronchoscopy and hearing test. Whole-exome sequencing was performed for the patient and both parents. The pediatric patient was diagnosed as Kartagener syndrome with the typical symptoms of ciliary dyskinesia including bronchiectasis, sinusitis, conductive hearing loss and situs inversus along with a reduced nasal NO concentration and ciliary abnormalities. The patient carried two novel compound heterozygous mutations in DNAH5, NM_001369:c.12813G > A (p. Trp4271Term) and NM_001369:c.9365delT (p. Leu3122Term). Both mutations lead to premature stop codons and thus are pathogenic. The p. Trp4271Term and p. Leu3122Term mutations were inherited from the father and the mother of the patient individually. A literature review was also conducted to summarize DNAH5 mutations in pediatric patients with Kartagener syndrome across different ethnic groups.

CONCLUSIONS

Our study provides a good example of the diagnosis of Kartagener syndrome in pediatric patients using a series of diagnostic tests combined with genetic testing. Two novel loss-of-function mutations in DNAH5 were identified and validated in a pediatric patient with Kartagener syndrome.

The Antimicrobial Activity of Peripheral Blood Neutrophils Is Altered in Patients with Primary Ciliary Dyskinesia

The airways of patients with primary ciliary dyskinesia (PCD) contain persistently elevated neutrophil numbers and CXCL8 levels. Despite their abundance, neutrophils fail to clear the airways from bacterial infections. We investigated whether neutrophil functions are altered in patients with PCD. Neutrophils from patients and healthy controls (HC) were isolated from peripheral blood and exposed to various bacterial stimuli or cytokines. Neutrophils from patients with PCD were less responsive to low levels of fMLF in three different chemotaxis assays (p < 0.05), but expression of the fMLF receptors was unaltered. PCD neutrophils showed normal phagocytic function and expression of adhesion molecules. However, PCD neutrophils produced less reactive oxygen species upon stimulation with bacterial products or cytokines compared to HC neutrophils (p < 0.05). Finally, the capacity to release DNA, as observed during neutrophil extracellular trap formation, seemed to be reduced in patients with PCD compared to HC (p = 0.066). These results suggest that peripheral blood neutrophils from patients with PCD, in contrast to those of patients with cystic fibrosis or COPD, do not show features of over-activation, neither on baseline nor after stimulation. If these findings extend to lung-resident neutrophils, the reduced neutrophil activity could possibly contribute to the recurrent respiratory infections in patients with PCD.

Anesthetic management of a patient with situs inversus totalis undergoing coronary artery bypass grafting surgery: a case report

BACKGROUND

Anesthetic management of coronary artery bypass grafting surgery (CABG) in a dextrocardia patient with situs inversus totalis is rarely encountered and seldom reported in the literature.

CASE PRESENTATION

A 76-year-old Japanese female patient had been diagnosed with situs inversus totalis and coronary artery disease of 3 vessels, and she subsequently underwent elective CABG. A preoperative examination showed almost normal results. ECG showed right deviation with the normal lead position. In the operating room, ECG leads were applied in reverse. Pulmonary artery catheterization was performed via the left internal jugular vein. A transesophageal echocardiography (TEE) probe was introduced without difficulty. A different angle was needed to acquire the desired views because of her atypical anatomy.

CONCLUSION

Careful perioperative evaluation, intraoperative management, and inspection of multiplane angle and probe adjustments in TEE are needed for anatomically abnormal patients.

International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

Two novel mutations in the DNAH11 gene in primary ciliary dyskinesia (CILD7) with considerable variety in the clinical and beating cilia phenotype

Background

Diagnosis of primary ciliary dyskinesia (PCD) still remains a challenge, especially with mutations in the Dynein Arm Heavy Chain 11 (DNAH11) gene. Classical diagnostic measures like Transmission Electron Microscopy (TEM) are not applicable for mutations in the DNAH11 gene since ultrastructural defects of the ciliary apparatus are absent. Novel mutations encoding for PCD appear all the time with considerable variation in the clinical picture, making it necessary to update data bases and guidelines for PCD diagnostics.

Methods

In this study we examined two unrelated, Finnish families with symptoms of PCD applying the clinical scoring system: Primary ciliary dyskinesia Rule (PICADAR), high speed video microscopy analysis (HSVMA) for ciliary movement, a commercially available gene panel analysis and nasal Nitric Oxide (nNO) measurements if applicable.

Results

Two, likely pathogenic variants in the DNAH11 gene (c.2341G > A, p. (Glu781Lys) ja c.7645 + 5G > A) were detected. In the first family, compound heterozygous mutations led to disease manifestation in two of 4 children, which showed a similar phenotype of cilia beating pattern but marked differences in disease severity. In the second family, all three children were homozygotes for the c.2341G > A p.(Glu781Lys) mutation and showed a similar degree of disease severity. However, the phenotype of cilia beating pattern was different ranging from stiff, static cilia to a hyperkinetic movement in one of these children.

Conclusions

In this study we describe two Finnish families with PCD, revealing two novel mutations in the DNAH11 gene which show considerable variety in the clinical and beating cilia phenotype. The results of this study show the clinician that PCD can be much milder than generally expected and diagnosis demands a combination of measures which are only successful in experienced hands. Chronic and repeatedly treated wet cough should raise suspicion of PCD, referring the patient for further diagnostics to a specialised PCD centre.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12881-020-01171-2.

A novel genetic variant in DNAI2 detected by custom gene panel in a newborn with Primary Ciliary Dyskinesia: case report

BACKGROUND

Primary ciliary dyskinesia (PCD) is a highly heterogeneous genetic disorder caused by defects in motile cilia. The hallmark features of PCD are the chronic infections of the respiratory tract, moreover, clinical manifestations include also laterality defects and risk of male infertility. Clinical phenotypes of PCD are the result of mutations in genes encoding components of axonema or factors involved in axonemal assembly. Recent studies have identified over 45 PCD-associated genes, therefore, molecular analysis represents a powerful diagnostic tool to confirm and uncover new genetic causes of this rare disease.

CASE PRESENTATION

Here, we describe a female infant of Moroccan origin with normal pressure hydrocephalus (NPH) in addition to most common PCD symptoms. Transmission Electron Microscopy (TEM) and molecular tests, such as a Next generation Sequencing panel and a custom array CGH, were performed for diagnosis of PCD. TEM revealed outer dynein arm (ODA) defects, whilst molecular analyses detected a novel 6,9 kb microdeletion in DNAI2 gene.

CONCLUSIONS

Since DNAI2 mutations are very rare, this case report contributes to better delineate the important role of DNAI2 as causative of PCD phenotype, suggesting, furthermore, that the variations in DNAI2 may be as a new genetic risk factor for NPH. Indeed, although the association of hydrocephalus with PCD has been well documented, however, only a small number of human patients show this defect. Furthermore, this study highlights the importance of high-throughput technologies in advancing our understanding of heterogeneous genetic disorders.

Primary Ciliary Dyskinesia with Refractory Chronic Rhinosinusitis

Patient: Male, 49-year-old

Final Diagnosis: Situs inversus

Symptoms: Cough • nasal congestion • nasal obstruction

Medication:—

Clinical Procedure: —

Specialty: Otolaryngology

Diagnosis and management of chronic cough: similarities and differences between children and adults

Cough is a natural process that protects the airway. Cough can occur spontaneously or voluntarily. It is considered chronic when it is present for longer than 4 weeks in children or 8 weeks in adults. In both, chronic cough causes patient distress and increased healthcare utilization. Etiologies of pediatric chronic cough include asthma, protracted bacterial bronchitis, tracheomalacia, habit cough, and various systemic disorders. While some diagnoses are identifiable by careful history alone, others require testing guided by specific pointers. Flexible fiberoptic bronchoscopy has been an important tool to identify etiologies of chronic cough that were not otherwise apparent. In adults, asthma and bronchitis are well-defined etiologies of chronic cough, but much chronic cough in adults is largely a conundrum.

Reviews of adult chronic cough report that at least 40% of adults with chronic cough have no medical explanation. Gastroesophageal reflux and upper airway cough syndrome (a.k.a. post-nasal drip) have been common diagnoses of chronic cough, but those diagnoses have no support from controlled clinical trials and have been subjected to multiple published critiques. Cough hypersensitivity is considered to be an explanation for chronic cough in adults who have no other confirmed diagnosis. Gabapentin, a neuromodulator, has been associated with a modest effect in adults, as has speech pathology. While habit cough has not generally been a diagnosis in adults, there is evidence for a behavioral component in adults with chronic cough. Treatment for a specific diagnosis provides a better outcome than trials of cough suppression in the absence of a specific diagnosis. More data are needed for chronic cough in adults to examine the hypothesized cough hypersensitivity and behavioral management. This article reviews etiologies and the treatment of chronic cough in children and the conundrum of diagnosing and treating chronic cough in adults.

Knowledge of Rare Respiratory Diseases among Paediatricians and Medical School Students

Alpha-1-antitrypsin deficiency (AATD) and primary ciliary dyskinesia (PCD) are underdiagnosed rare diseases showing a median diagnostic delay of five to ten years, which has negative effects on patient prognosis. Lack of awareness and education among healthcare professionals involved in the management of these patients have been suggested as possible causes. Our aim was to assess knowledge of these diseases among paediatricians and medical school students to determine which knowledge areas are most deficient. A survey was designed with questions testing fundamental aspects of the diagnosis and treatment of AATD and PCD. A score equal to or greater than 50% of the maximum score was set as the level necessary to ensure a good knowledge of both diseases. Our results indicate a profound lack of knowledge of rare respiratory diseases among paediatric professionals and medical students, suggesting that it is necessary to increase rare respiratory diseases training among all physicians responsible for suspecting and diagnosing them; this will allow early diagnosis and the setup of preventive measures and appropriate early-stage treatment. The first step in closing this knowledge gap could be to include relevant material in the medical syllabus.

Understanding Primary Ciliary Dyskinesia: Experience From a Mediterranean Diagnostic Reference Centre

Background: Due to the lack of a gold standard diagnostic test, reference centres with experienced personnel and costly procedures are needed for primary ciliary dyskinesia (PCD) diagnostics. Diagnostic flowcharts always start with clinical symptoms. Therefore, the aim of this work is to define differential clinical criteria so that only patients clinically compatible with PCD are referred to reference centres. Materials and methods: 18 variables from 476 Mediterranean patients with clinically suspicious PCD were collected. After analysing cilia function and ultrastructure, 89 individuals were diagnosed with PCD and 387 had a negative diagnosis. Simple logistic regression analysis, considering PCD as a dependent variable and the others as independent variables, was done. In order to define the variables that best explain PCD, a step-wise logistic regression model was defined. Aiming to classify individuals as PCD or PCD-like patients, based on variables included in the study, a classification and regression tree (CART) was designed. Results and conclusions: Simple logistic regression analysis shows statistically significant association between age at the beginning of their symptomatology, periodicity, fertility, situs inversus, recurrent otitis, atelectasis, bronchiectasis, chronic productive cough, rhinorrea, rhinusinusitis and recurrent pneumonias, and PCD. The step-wise logistic regression model selected situs inversus, atelectasis, rhinorrea, chronic productive cough, bronchiectasis, recurrent pneumonias, and otitis as PCD predictive variables (82% sensitivity, 88% specificity, and 0.92 Area Under the Curve (AUC)). A decision tree was designed in order to classify new individuals based on pansinusitis, situs inversus, periodicity, rhinorrea, bronchiectasis, and chronic wet cough.

Mucociliary Transport in Healthy and Cystic Fibrosis Pig Airways

Cystic fibrosis (CF) lung disease is the major cause of morbidity and mortality in people with CF. Abnormal mucociliary transport has been the leading hypothesis for the underlying pathogenesis of CF airway disease. However, this has been difficult to investigate at very early time points. A porcine CF model, which recapitulates many features of CF disease in humans, enables studies to be performed in non-CF and CF pigs on the day that they are born. In newborn CF pigs, we found that under basal conditions, mucociliary transport rates in non-CF and CF pigs are similar. However, after cholinergic stimulation, which stimulates submucosal gland secretion, particles become stuck in the CF airways owing to a failure of mucus strands to release from submucosal glands. In this review, we summarize these recent discoveries and also discuss the morphology, composition, and function of mucins in the porcine lung.

Primary ciliary dyskinesia caused by a large homozygous deletion including exons 1-4 of DRC1 in Japanese patients with recurrent sinopulmonary infection

BACKGROUND

Diffuse panbronchiolitis (DPB) is a sinopulmonary disease mainly affecting Asian populations. Primary ciliary dyskinesia (PCD) is a genetically heterogeneous disorder impairing ciliary structure and function. These two disorders are not easily distinguished by clinical signs and symptoms.

METHODS

In 105 Japanese patients with recurrent sinopulmonary infection, initially diagnosed with DPB, and 37 patients with recurrent airway infection diagnosed in adulthood, the deletion allele of DRC1 or CCDC164, recently recognized as a pathogenic PCD gene variant, was searched using a multiplexed PCR-based method, and the deletion breakpoints and other variants around the gene were determined by Sanger sequencing and targeted resequencing.

RESULTS

A large homozygous deletion in DRC1 was identified in three of the 142 patients. Furthermore, heterozygous carriers of the deletion with the same breakpoint were found with the allele frequency of 0.002 in the healthy Japanese population, indicating that this loss-of-function variant may be acting as a common mutation causing PCD in Japanese.

CONCLUSION

PCD caused by the DRC1 defect is not readily identified by either high-speed video-microscopy or ciliary ultrastructure analysis, posing significant difficulties in reaching a correct diagnosis without the aid of genetic tests. Careful investigation of the causes of sinopulmonary diseases is warranted in Asian populations.

Diagnosis of Primary Ciliary Dyskinesia. An Official American Thoracic Society Clinical Practice Guideline

BACKGROUND

This document presents the American Thoracic Society clinical practice guidelines for the diagnosis of primary ciliary dyskinesia (PCD).

TARGET AUDIENCE

Clinicians investigating adult and pediatric patients for possible PCD.

METHODS

Systematic reviews and, when appropriate, meta-analyses were conducted to summarize all available evidence pertinent to our clinical questions. Evidence was assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach for diagnosis and discussed by a multidisciplinary panel with expertise in PCD. Predetermined conflict-of-interest management strategies were applied, and recommendations were formulated, written, and graded exclusively by the nonconflicted panelists. Three conflicted individuals were also prohibited from writing, editing, or providing feedback on the relevant sections of the manuscript.

RESULTS

After considering diagnostic test accuracy, confidence in the estimates for each diagnostic test, relative importance of test results studied, desirable and undesirable direct consequences of each diagnostic test, downstream consequences of each diagnostic test result, patient values and preferences, costs, feasibility, acceptability, and implications for health equity, the panel made recommendations for or against the use of specific diagnostic tests as compared with using the current reference standard (transmission electron microscopy and/or genetic testing) for the diagnosis of PCD.

CONCLUSIONS

The panel formulated and provided a rationale for the direction as well as for the strength of each recommendation to establish the diagnosis of PCD.

Individualized physical training in the therapy of Primary Ciliary Dyskinesia - A case report

Background

Primary Ciliary Dyskinesia (PCD) is an autosomal recessive disease, characterized by ciliary dysfunction and impaired mucociliary clearance. Previous studies have indicated a low physical fitness in PCD patients but currently it is not known whether physical training beneficially affects fitness, inflammatory markers and quality of life.

Case presentation

The patient was a Caucasian male (67.0 kg, 183.3 cm), born in 1984 and was diagnosed with the Kartagener Syndrome (i.e. PCD) right after birth. He was prescribed structured physical training over a period of almost two years (from August 2017-June 2019) and was assessed regularly. Aerobic fitness improved throughout the intervention period, but no systematic changes were observed in inflammatory markers and overall quality of life.

Conclusions

Our data provides reasoning to stress the implementation of structured physical training to enhance physical performance also in the management of PCD.

Identification of Pathogenic Mutations and Investigation of the NOTCH Pathway Activation in Kartagener Syndrome

Primary ciliary dyskinesia (PCD), a rare genetic disorder, is mostly caused by defects in more than 40 known cilia structure-related genes. However, in approximately 20-35% of patients, it is caused by unknown genetic factors, and the inherited pathogenic factors are difficult to confirm. Kartagener syndrome (KTS) is a subtype of PCD associated with situs inversus, presenting more complex genetic heterogeneity. The aim of this study was to identify pathogenic mutations of candidate genes in Chinese patients with KTS and investigate the activation of the heterotaxy-related NOTCH pathway. Whole-exome sequencing was conducted in five patients with KTS. Pathogenic variants were identified using bioinformatics analysis. Candidate variants were validated by Sanger sequencing. The expression of the NOTCH pathway target genes was detected in patients with KTS. We identified 10 KTS-associated variants in six causative genes, namely, CCDC40, DNAH1, DNAH5, DNAH11, DNAI1, and LRRC6. Only one homozygote mutation was identified in LRRC6 (c.64dupT). Compound heterozygous mutations were found in DNAH1 and DNAH5. Six novel mutations were identified in four genes. Further analyses showed that the NOTCH pathway might be activated in patients with KTS. Overall, our study showed that compound heterozygous mutations widely exist in Chinese KTS patients. Our results demonstrated that the activation of the NOTCH pathway might play a role in the situs inversus pathogenicity of KTS. These findings highlight that Kartagener syndrome might be a complex genetic heterogeneous disorder mediated by heterozygous mutations in multiple PCD- or cilia-related genes.

Three Cases of Primary Ciliary Dyskinesia Combined With Reduced Exhaled Nitric Oxide

OBJECTIVES

The diagnosis of primary ciliary dyskinesia (PCD) is often delayed in part related to the limitations of the available diagnostic tests. We present 3 cases of PCD diagnosed using an exhaled nitric oxide (eNO) measurement.

METHODS

Three cases with a clinical phenotype consistent with PCD were evaluated using an eNO assay with additional transmission electron microscopy (TEM) and/or genetic panel testing.

RESULTS

One male and 2 female patients presented with common symptoms included recurrent respiratory infection from early childhood and a history of neonatal respiratory distress as term newborn. Two of them had situs inversus totalis. Fractional eNO measurement revealed extremely low NO levels, and subsequently, TEM analysis confirmed ciliary ultrastructural defects in all patients. One patient had compound heterozygous mutation of the PCD-causative gene (DNAH5) identified using next generation sequencing.

CONCLUSION

Our report stresses the reliability of eNO measurement in the diagnosis of PCD, accompanied by clinical phenotypes and additional diagnostic tools, such as TEM analysis and genetic testing.

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.

Additional role of bronchial mucosal biopsy for ciliary structural abnormality in diagnosis of primary ciliary dyskinesia

Background

Transmission electron microscopy (TEM) is one of diagnostic tests for primary ciliary dyskinesia (PCD). The mucosal samples obtained for cilia examination are generally procured from the nasal turbinate, but these specimens often yield inadequate results. The bronchial mucosa is recognized as an alternative sample, but no study has examined the additional utility of bronchial mucosa compared with nasal mucosa in the diagnosis of PCD.

Methods

The medical records of 96 patients who underwent TEM for suspected PCD between April 1997 and June 2017 were reviewed. Patients were divided into three groups based on the site of mucosal biopsy: nasal biopsy (NB) group with nasal mucosal biopsy only; bronchial biopsy (BB) group with bronchial mucosal biopsy only; and nasal and bronchial biopsy (NBB) group with a combination of nasal and bronchial mucosal biopsies.

Results

The rate of PCD diagnosis was 28.8% (17/59) in the NB group, 41.2% (7/17) in the BB group, and 60.0% (12/20) in the NBB group. The yield of PCD diagnosis significantly increased in the NBB group compared with the NB group (P=0.012). In the NBB group, 25.0% (5/20) of patients were diagnosed with PCD by nasal mucosal biopsy, and 35.0% (7/20) of patients were additionally diagnosed by bronchial mucosal biopsy. The presence of sinusitis or bronchiectasis was not associated with prediction of PCD diagnosis from nasal or bronchial mucosal biopsy.

Conclusions

The combination of nasal and bronchial mucosal biopsy for TEM showed higher yields of PCD diagnosis than nasal mucosal biopsy alone.

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.

Recurrent bacterial pneumonia in Irish Wolfhounds: Clinical findings and etiological studies

BACKGROUND

Increased incidence of bacterial pneumonia (BP) has been reported in Irish Wolfhounds (IWHs), and recurrence of BP is common. The etiology of recurrent pneumonia in IWHs is largely unknown.

OBJECTIVES

To describe clinical findings in IWHs with recurrent BP and investigate possible etiologies.

ANIMALS

Eleven affected IWHs, 25 healthy IWHs, 28 healthy dogs of other Sighthound breeds, and 16 healthy dogs of other breeds.

METHODS

Prospective cross-sectional observational study. All affected IWHs underwent thorough clinical examinations including thoracic radiographs, thoracic computed tomography, electron microscopic evaluation of ciliary structure, and bronchoscopy and bronchoalveolar lavage fluid (BALF) cytology and culture. Serum and BALF immunoglobulin concentrations were measured using an ELISA method, and peripheral blood lymphocyte subpopulations were analyzed using flow cytometry. Esophageal function was assessed by fluoroscopy (n = 2).

RESULTS

Median age of onset was 5.0 years (range, 0.4-6.5 years), and when presented for study, dogs had experienced a median of 5 previous episodes of BP (range, 2-6). The following predisposing factors to BP were detected: focal bronchiectasis (10/11), unilateral (2/9) and bilateral (1/9) laryngeal paralysis, and esophageal hypomotility (2/2). Local or systemic immunoglobulin deficiencies or primary ciliary defects were not detected.

CONCLUSIONS AND CLINICAL IMPORTANCE

Recurrent BP affects mostly middle-aged and older IWHs without any evident immune deficit or primary ciliary defects. Focal BE was a frequent finding in affected dogs and likely contributed to the development of recurrent respiratory infections. Laryngeal and esophageal dysfunction identified in a minority of dogs may contribute to recurrent BP.

CCDC114 is mutated in patient with a complex phenotype combining primary ciliary dyskinesia, sensorineural deafness, and renal disease

Ciliopathies-are widely recognized and associated with a wide variety of developmental and degenerative disorders. Most cilia-related diseases have renal manifestation, and there is a cross- overlapping relationship between gene mutations and cilia disease. Here, we investigated the clinical and pathological manifestation of a rare disease patient. We present the case of a 15-year-old child with dysplasia and multiple-organ damage who was initially diagnosed with nephrotic syndrome. The patient's kidney disease progressed to renal failure and received hemodialysis 10 months after renal biopsy. The individual presented primary ciliary dyskinesia (PCD) and additional symptoms including sensorineural deafness, kidney dysplasia, severe kidney function loss, and congenital heart disease which potentially linked to primary cilia deficiency. Cilia immunofluorescence of renal tissue showed a decrease in the number of cilium of the patient compared to the normal kidney. We identified a site mutation in CCDC114 (NM_144577 exon7 c. 596Cå T p. Ala199Val) by whole-exon sequences. We found that CCDC114 located at the basal body at cilia and the knockdown of CCDC114 could affect the occurrence of cilia in hRPE1 cells. The previous study of CCDC114 mainly lies in the motile cilia, and this study found that its impact on primary cilia thus broadened the understanding of overlapping function of different types of cilia.

Fitness and lung function in children with primary ciliary dyskinesia and cystic fibrosis

BACKGROUND

Peak oxygen uptake (VO_2peak) is associated with morbidity and mortality in health and disease, and provides important information of global physical health not achieved from standard pulmonary function tests. Primary ciliary dyskinesia (PCD) and cystic fibrosis (CF) are genetically determined diseases involving different basic defects, but both showing impaired mucociliary clearance leading to chronic infections and pulmonary destruction early in life. PCD is generally considered a milder disease than CF and it is hypothesized that children with CF would have consistently lower VO_2peak and pulmonary function than children with PCD.

METHODS

We performed a prospective, observational single-center, clinical cohort study of VO_2peak and pulmonary function in age and gender matched schoolchildren, at two occasions 12 months apart.

RESULTS

VO_2peak was persistently (at baseline and after 12 months) and significantly reduced in the 22 patients with PCD (z-score = -0.89 and -1.0) and 24 with CF (z-score = -0.94 and -1.1), included in the study. Abnormal VO_2peak was detected in a larger proportion of children with PCD (≈30%) than CF (≈13%). Moreover, children with PCD exhibited persistently lower FEV₁ (p < 0.0001 at first visit and p = 0.001 at second visit) while FEF_25-75 and FVC differed only at baseline. Indeed, a retrospective analysis comparing lung function over the last year in our entire PCD and CF populations between 6 and 18 years of age, revealed lower values in patients with PCD (FEV₁ z-score, p = 0.0004, FVC z-score p < 0.0001, FEF_25-75 z-score p = 0.008).

CONCLUSION

This is the first report indicating that cardiopulmonary fitness is equally and consistently reduced in both children with PCD and CF along with a consistent lower pulmonary function in PCD compared with CF. A certain reservation for possible selection bias and the small number of patients is necessary. However, increased focus on early diagnosis, evidence-based treatment regimens and close clinical monitoring in PCD are warranted.

Nasal saline irrigation in pediatric rhinosinusitis: A systematic review

OBJECTIVE

To determine the efficacy of nasal saline irrigation (NSI) in reducing symptoms and improving quality of life in pediatric patients with acute (ARS) or chronic (CRS) rhinosinusitis.

DATA SOURCES

We searched the PubMed/MEDLINE and Embase electronic databases (indexed January, 1950 through April, 2017).

REVIEW METHODS

Studies assessing the efficacy of NSI in pediatric patients with ARS or CRS were selected for analysis. Outcome measures, including symptom scores and parental surveys, were analyzed. Two independent reviewers evaluated each abstract and article.

RESULTS

Of the 272 articles identified using our search strategy, only 1 study, focusing on the use of NSI in pediatric ARS, met all inclusion criteria. No studies investigating NSI in pediatric CRS were included for analysis. In general, studies demonstrated significant improvement of symptom scores with the use of NSI in pediatric rhinosinusitis; but, the use of varied outcome measures, control treatments, and NSI delivery made including studies and drawing conclusions difficult. No quantitative meta-analysis could be performed.

CONCLUSION

NSI may provide benefit for ARS in children; however, additional high-quality studies with defined outcome measures are needed to determine the quantitative efficacy of this therapy in the pediatric patients with rhinosinusitis-especially in pediatric CRS.

Compound Heterozygous Variants in the Coiled-Coil Domain Containing 40 Gene in a Chinese Family with Primary Ciliary Dyskinesia Cause Extreme Phenotypic Diversity in Cilia Ultrastructure

Purpose: Primary ciliary dyskinesia (PCD) is a rare genetic disorder manifested with recurrent infections of respiratory tract and infertility. Mutations in more than 20 genes including the Coiled-Coil Domain Containing 40 (CCDC40) gene are associated with PCD. A Chinese proband with a clinical diagnosis of PCD was analyzed for mutations in these genes to identify the genetic basis of the disease in the family. The proband showed altered mucociliary clearance of the airways, various degree of hyperemia and edema of the mucous membrane, left/right body asymmetry, infertility and ultrastructural abnormality of cilia in both sperm and bronchioles. Methods: The DNA from the proband was analyzed for genetic variation in a subset of genes known to cause PCD using targeted next generation sequencing in order to understand the molecular and genetic basis of the PCD in present family. The result of targeted next generation sequencing has been validated by Sanger sequencing and q-PCR. Results: Targeted next-generation sequencing identified two novel mutations (c.1259delA and EX17_20 deletion) in CCDC40 gene that causes abnormal CCDC40 mRNA expression. These two novel variants cause disorganization of axoneme filaments, which resulted in reduction of sperm motility and phenotypic diversity in ultrastructure of cilia in the proband. Conclusion: These findings highlight the significance of the mutations in CCDC40 as novel candidates for genetic testing in PCD patients as well as the key role of ICSI treatment for the families affected by this ciliary dysmotility. Our findings showed that our work enriched the performance of cilia ultrastructure which were not previously reported in PCD patients.

Primary Ciliary Dyskinesia Due to Microtubular Defects is Associated with Worse Lung Clearance Index

Purpose

Primary ciliary dyskinesia (PCD) is characterised by repeated upper and lower respiratory tract infections, neutrophilic airway inflammation and obstructive airway disease. Different ultrastructural ciliary defects may affect lung function decline to different degrees. Lung clearance index (LCI) is a marker of ventilation inhomogeneity that is raised in some but not all patients with PCD. We hypothesised that PCD patients with microtubular defects would have worse (higher) LCI than other PCD patients.

Methods

Spirometry and LCI were measured in 69 stable patients with PCD. Age at testing, age at diagnosis, ethnicity, ciliary ultrastructure, genetic screening result and any growth of Pseudomonas aeruginosa was recorded.

Results

Lung clearance index was more abnormal in PCD patients with microtubular defects (median 10.24) than those with dynein arm defects (median 8.3, p = 0.004) or normal ultrastructure (median 7.63, p = 0.0004). Age is correlated with LCI, with older patients having worse LCI values (p = 0.03, r = 0.3).

Conclusion

This study shows that cilia microtubular defects are associated with worse LCI in PCD than dynein arm defects or normal ultrastructure. The patient’s age at testing is also associated with a higher LCI. Patients at greater risk of obstructive lung disease should be considered for more aggressive management. Differences between patient groups may potentially open avenues for novel treatments.

Electronic supplementary material

The online version of this article (10.1007/s00408-018-0086-x) contains supplementary material, which is available to authorized users.

Lessons From Unilateral Loss of Cilia: Early Nasal Nitric Oxide Gas Mixing and the Role of Sinus Patency in Determining Nasal Nitric Oxide

Nasal nitric oxide (nNO) measurement is a diagnostic test for primary ciliary dyskinesia (PCD). Here, we have shown the development of unilateral PCD-like symptoms associated with low nNO. A 60-year-old man had been previously healthy but developed unilateral, severe pansinusitis. He required surgical drainage of all left sinuses, and biopsies showed loss of the ciliated epithelium. At 4 weeks, he had unilateral (left-sided), profuse, clear rhinorrhea characteristic of PCD, and his surgical ostia were all patent endoscopically. His left-sided nNO was less than the right side by 37 ± 1.2 nL/min; this difference decreased to 18 ± 0.87 nL/min at 5 weeks and was gone by 6 weeks when his symptoms resolved. Measurements of 2- and 10-second measurements, in addition to standard nNO measurements, identified this discordance. We conclude that nNO reflects, in part, the production of NO by the ciliated epithelium, not just in the absence or occlusion of sinuses. Early (nasal/sinus volume) measures may be better for diagnosing PCD in than standard, steady-state assays in certain populations.

Monocytes from patients with Primary Ciliary Dyskinesia show enhanced inflammatory properties and produce higher levels of pro-inflammatory cytokines

Patients with Primary Ciliary Dyskinesia (PCD) suffer from recurrent upper and lower airway infections due to defects in the cilia present on the respiratory epithelium. Since chronic inflammatory conditions can cause changes in innate immune responses, we investigated whether monocytes isolated from the peripheral blood of pediatric PCD patients respond differently to inflammatory stimuli, compared to monocytes from healthy children and adults. The receptor for C5a (C5aR) was upregulated in PCD, whereas expression levels of the leukocyte chemoattractant receptors CCR1, CCR2, CCR5, BLT1 and FPR1 on PCD monocytes were similar to those on monocytes from healthy individuals. Also in vitro migration of PCD monocytes towards the ligands of those receptors (CCL2, fMLP, C5a and LTB4) was normal. Compared to healthy children, PCD patients had a higher percentage of the non-classic monocyte subset (CD14+CD16++) in circulation. Finally, PCD monocytes produced higher levels of pro-inflammatory cytokines (IL-1β and TNF-α) and chemokines (CCL3, CCL5, CCL18 and CCL22) in response to LPS, peptidoglycan and/or dsRNA stimulation. These data suggest that monocytes might exacerbate inflammatory reactions in PCD patients and might maintain a positive feedback-loop feeding the inflammatory process.