Primary ciliary dyskinesia, an orphan disease

Characterization of a DRC1 null variant associated with primary ciliary dyskinesia and female infertility

PROPOSE

We here present a female case with primary ciliary dyskinesia (PCD) and infertility. In this report, we also present the evaluation of the patient family, including her twin sister, also with PCD and infertility.

METHODS

Confirmation of the PCD clinical diagnosis was performed through assessment of cilia motility, by high-speed video microscopy (HSVM), axoneme ultrastructure, by transmission electron microscopy (TEM), and genetic characterization, by whole-exome sequence (WES). Gene expression studies used qPCR for mRNA expression and immunofluorescence to determine cell protein localization.

RESULTS

We identified a homozygous nonsense variant in the DRC1 gene (NM 145038.5:c.352C>T (p.Gln118Ter)) in the female patient with PCD and infertility that fit the model of autosomal recessive genetic transmission. This variant eventually results in a dyskinetic ciliary beat with a lower frequency and a partial lack of both dynein arms as revealed by TEM analysis. Moreover, this variant implies a decrease in the expression of DRC1 mRNA and protein. Additionally, expression analysis suggested that DRC1 may interact with other DRC elements.

CONCLUSIONS

Our findings suggest that the DRC1 null variant leads to PCD associated with infertility, likely caused by defects in axoneme from Fallopian tube cilia. Overall, our outcomes contribute to a better understanding of the genetic factors involved in the pathophysiology of PCD and infertility, and they highlight the interaction of different genes in the patient phenotype, which should be investigated further because it may explain the high heterogeneity observed in PCD patients.

Observational study of health utilities in adult primary ciliary dyskinesia patients: preliminary data on associations with molecular diagnosis, clinical phenotype and HRQOL measures

Background

Primary ciliary dyskinesia (PCD) is a congenital disorder characterized by chronic respiratory morbidity. To date, there is no information on PCD-specific preference-based quality of life measures such as health utilities (HU). We cross-sectionally assessed HU in adult PCD patients and explored relationships with genotype, phenotype and quality of life (QOL)-PCD scales.

Methods

Diagnostic testing was performed according to international guidelines, while participants completed the visual analog scale (VAS), time trade off (TTO), standard gamble (SG), and EuroQol 5 dimensions (EQ5D) HU instruments, as well as the QOL-PCD questionnaire. Hierarchical regression was used to identify the QOL-PCD scales that are most predictive of HU.

Results

Among 31 patients, median HU are 0.75 (VAS), 0.86 (EQ5D), 0.91 (TTO) and 0.99 (SG). The underlying genotype is not associated with HU measures. VAS and EQ5D are associated with lung function, while TTO and SG values are not sensitive to any of the examined factors. Among the QOL-PCD scales, physical functioning and lower respiratory symptoms explained much of VAS (R²= 0.419) and EQ5D (R²= 0.538) variability.

Conclusions

Our study demonstrates that HU elicitation in PCD is feasible using both direct and indirect methods. Overall, HU scores are relatively high among adult patients, with higher scores observed in SG and TTO, followed by EQ5D and VAS. VAS and EQ5D HU values are sensitive to lung function as well as to QOL-PCD physical functioning and lower respiratory symptom scores.

The apical ciliary adhesion complex is established at the basal foot of motile cilia and depends on the microtubule network

The Ciliary Adhesion (CA) complex forms in close association with the basal bodies of cilia during the early stages of ciliogenesis and is responsible for mediating complex interactions with the actin networks of multiciliated cells (MCCs). However, its precise localization with respect to basal body accessory structures and the interactions that lead to its establishment in MCCs are not well understood. Here, we studied the distribution of the CA proteins using super-resolution imaging and possible interactions with the microtubule network. The results of this study reveal that the apical CA complex forms at the distal end of the basal foot and depends on microtubules. Our data also raise the possibility that CAs may have additional roles in the regulation of the organization of the microtubule network of MCCs.

Depletion of Ift88 in thymic epithelial cells affects thymic synapse and T-cell differentiation in aged mice

Primary cilia are ubiquitous hair-like organelles, usually projecting from the cell surface. They are essential for the organogenesis and homeostasis of various physiological functions, and their dysfunction leads to a plethora of human diseases. However, there are few reports on the role of primary cilia in the immune system; therefore, we focused on their role in the thymus that nurtures immature lymphocytes to full-fledged T cells. We detected primary cilia on the thymic epithelial cell (TEC) expressing transforming growth factor β (TGF-β) receptor in the basal body, and established a line of an intraflagellar transport protein 88 (Ift88) knockout mice lacking primary cilia in TECs (Ift88-TEC null mutant) to clarify their precise role in thymic organogenesis and T-cell differentiation. The Ift88-TEC null mutant mice showed stunted cilia or lack of cilia in TECs. The intercellular contact between T cells and the "thymic synapse" of medullary TECs was slightly disorganized in Ift88-TEC null mutants. Notably, the CD4- and CD8-single positive thymocyte subsets increased significantly. The absence or disorganization of thymic cilia downregulated the TGF-β signaling cascade, increasing the number of single positive thymocytes. To our knowledge, this is the first study reporting the physiological role of primary cilia and Ift88 in regulating the differentiation of the thymus and T cells.

Analysis of the diagnosis of Japanese patients with primary ciliary dyskinesia using a conditional reprogramming culture

BACKGROUND

Primary ciliary dyskinesia (PCD) is diagnosed through multiple methods, including transmission electron microscopy (TEM), a high-speed video microscopy analysis (HSVA), immunofluorescence (IF), and genetic testing. A primary cell culture has been recommended to avoid the misdiagnosis of secondary ciliary dyskinesia derived from infection or inflammation and improve diagnostic accuracy. However, primary cells fail to differentiate into ciliated cells through repeated passages. The conditional reprogramming culture (CRC) method, a combination of a Rho-kinase inhibitor and fibroblast feeder cells, has been applied to cystic fibrosis. The goal of this study was to evaluate the value of CRC in diagnosing PCD in Japanese patients.

METHODS

Eleven patients clinically suspected of having PCD were included. Airway epithelial cells were obtained from an endobronchial forceps biopsy and cultured at the air-liquid interface (ALI) combined with CRC. Ciliary movement, ultrastructure, and mutated ciliary protein evaluation were performed using HSVA, TEM, and IF, respectively. Genetic testing was performed on some patients.

RESULTS

CRC yielded dense and well-differentiated ciliated cells with a high success rate (∼90%). In patients with PCD, the ciliary ultrastructure phenotype (outer dynein arm defects or normal ultrastructure) and IF findings (absence of the mutated ciliary protein) were confirmed after CRC. In DNAH11-mutant cases with normal ultrastructure by TEM, the HSVA revealed stiff and hyperfrequent ciliary beating with low bending capacity in CRC-expanded cells, thereby supporting the diagnosis.

CONCLUSIONS

CRC could be a potential tool for improving diagnostic accuracy and contributing to future clinical and basic research in PCD.

Association between maternal insecticide use and otitis media in one-year-old children in the Japan Environment and Children's Study

Otitis media (OM) is common among young children and is related to hearing loss. We investigated the association between maternal insecticide use, from conception to the first and second/third trimesters, and OM events in children in the first year of age. Data from Japan Environment and Children's Study were used in this prospective cohort study. Characteristics of patients with and without history of OM during the first year of age were compared. The association between history of OM in the first year and insecticide use was evaluated using logistic regression analysis. The study enrolled 98,255 infants. There was no significant difference in the frequency of insecticide use between groups. Insecticide use of more than once a week from conception to the first trimester significantly increased the occurrence of OM in children in the first year (odds ratio [OR] = 1.30, 95% confidence interval [CI] 1.01–1.67). The association between OM in the first year and insecticide use from conception to the first trimester was only significant in the group without daycare attendance (OR 1.76, 95% CI 1.30–2.38). Maternal insecticide use more than once a week from conception to the first trimester significantly increased OM risk in offspring without daycare attendance.

Sputum from patients with primary ciliary dyskinesia contains high numbers of dysfunctional neutrophils and inhibits efferocytosis

BACKGROUND

Primary ciliary dyskinesia (PCD) is a genetic disorder characterized by recurrent airway infection and inflammation. There is no cure for PCD and to date there are no specific treatments available. Neutrophils are a crucial part of the immune system and are known to be dysfunctional in many inflammatory diseases. So far, the role of the neutrophils in PCD airways is largely unknown. The purpose of this study was to investigate the phenotype and function of airway neutrophils in PCD, and compare them to blood neutrophils.

METHODS

Paired peripheral blood and spontaneously expectorated sputum samples from patients with PCD (n = 32) and a control group of patients with non-PCD, non-cystic fibrosis bronchiectasis (n = 5) were collected. The expression of neutrophil-specific surface receptors was determined by flow cytometry. Neutrophil function was assessed by measuring the extent of actin polymerization, production of reactive oxygen species (ROS) and release of neutrophil extracellular traps (NETs) in response to activating stimuli.

RESULTS

Sputum neutrophils displayed a highly activated phenotype and were unresponsive to stimuli that would normally induce ROS production, actin polymerization and the expulsion of NETs. In addition, PCD sputum displayed high activity of neutrophil elastase, and impaired the efferocytosis by healthy donor macrophages.

CONCLUSIONS

Sputum neutrophils in PCD are dysfunctional and likely contribute to ongoing inflammation in PCD airways. Further research should focus on anti-inflammatory therapies and stimulation of efferocytosis as a strategy to treat PCD.

The Short Term Influence of Chest Physiotherapy on Lung Function Parameters in Children With Cystic Fibrosis and Primary Ciliary Dyskinesia

Airway clearance therapy (ACT) is one of the cornerstone treatment modalities to improve mucociliary clearance for patients with bronchiectasis. The progression of lung disease in patients with bronchiectasis can be evaluated by spirometry and multiple breath washout (MBW) and it is advised to monitor these on a regular basis. However, the short term effect of ACT on spirometry and MBW parameters is insufficiently clear and this variability may impact standardization. For cystic fibrosis (CF), available literature refutes a short time effect on spirometry and MBW parameters in children, however, for primary ciliary dyskinesia (PCD) no data are available. We performed a single-center, prospective cross-over study to evaluate the short term effect of a single ACT session using positive expiratory pressure mask on forced expiratory volume in 1 s (FEV₁) and lung clearance index (LCI), derived from MBW, compared to no ACT (control) in pediatric patients with CF and PCD. A total of 31 children were included: 14 with PCD and 17 with CF. For the whole group, there was no difference in median change of FEV₁ pp between the treatment and the control group (p 0.969), nor in median change of LCI (p 0.294). For the CF subgroup, the mean change in FEV₁ pp with ACT was -1.4% (range -9 to + 5) versus -0.2% (range -6 to + 5) for no ACT (p 0.271), the mean change in LCI with ACT was + 0.10 (range -0.7 to + 1.2) versus + 0.17 (range -0.5 to + 2.8) for no ACT (p 0.814). In the PCD subgroup, the mean change in FEV₁ pp with ACT was + 1.0 (range -7 to + 8) versus -0.3 (range -6 to + 5) for no ACT (p 0.293) and the mean change in LCI with ACT was -0.46 (range -3.7 to + 0.9) versus -0.11 (range -1.4 to + 1.3) for no ACT (p 0.178). There was no difference between PCD and CF for change in FEV₁ pp after ACT (p = 0.208), nor for LCI (p = 0.095). In this small group of pediatric patients, no significant short-term effect of chest physiotherapy on FEV₁ pp nor LCI in PCD and CF values nor variability was documented.

Diagnosis of primary ciliary dyskinesia: discrepancy according to different algorithms

Background

Diagnosis of primary ciliary dyskinesia (PCD) is challenging since there is no gold standard test. The European Respiratory (ERS) and American Thoracic (ATS) Societies developed evidence-based diagnostic guidelines with considerable differences.

Objective

We aimed to compare the algorithms published by the ERS and the ATS with each other and with our own PCD-UNIBE algorithm in a clinical setting. Our algorithm is similar to the ERS algorithm with additional immunofluorescence staining. Agreement (Cohen's κ) and concordance between the three algorithms were assessed in patients with suspicion of PCD referred to our diagnostic centre.

Results

In 46 out of 54 patients (85%) the final diagnosis was concordant between all three algorithms (30 PCD negative, 16 PCD positive). In eight patients (15%) PCD diagnosis differed between the algorithms. Five patients (9%) were diagnosed as PCD only by the ATS, one (2%) only by the ERS and PCD-UNIBE, one (2%) only by the ATS and PCD-UNIBE, and one (2%) only by the PCD-UNIBE algorithm. Agreement was substantial between the ERS and the ATS (κ=0.72, 95% CI 0.53–0.92) and the ATS and the PCD-UNIBE (κ=0.73, 95% CI 0.53–0.92) and almost perfect between the ERS and the PCD-UNIBE algorithms (κ=0.92, 95% CI 0.80–1.00).

Conclusion

The different diagnostic algorithms lead to a contradictory diagnosis in a considerable proportion of patients. Thus, an updated, internationally harmonised and standardised PCD diagnostic algorithm is needed to improve diagnostics for these discordant cases.

There is no gold standard test for diagnosing PCD. The use of existing diagnostic algorithms leads to contradicting results in many patients (15% in this study). Thus, an updated and internationally harmonised diagnostic guideline is needed.https://bit.ly/2U19Vvq

Identification and Classification of Novel Genetic Variants: En Route to the Diagnosis of Primary Ciliary Dyskinesia

Primary ciliary dyskinesia (PCD) is a disease caused by impaired function of motile cilia. PCD mainly affects the lungs and reproductive organs. Inheritance is autosomal recessive and X-linked. PCD patients have diverse clinical manifestations, thus making the establishment of proper diagnosis challenging. The utility of next-generation sequencing (NGS) technology for diagnostic purposes allows for better understanding of the PCD genetic background. However, identification of specific disease-causing variants is difficult. The main aim of this study was to create a unique guideline that will enable the standardization of the assessment of novel genetic variants within PCD-associated genes. The designed pipeline consists of three main steps: (1) sequencing, detection, and identification of genes/variants; (2) classification of variants according to their effect; and (3) variant characterization using in silico structural and functional analysis. The pipeline was validated through the analysis of the variants detected in a well-known PCD disease-causing gene (DNAI1) and the novel candidate gene (SPAG16). The application of this pipeline resulted in identification of potential disease-causing variants, as well as validation of the variants pathogenicity, through their analysis on transcriptional, translational, and posttranslational levels. The application of this pipeline leads to the confirmation of PCD diagnosis and enables a shift from candidate to PCD disease-causing gene.

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.

Liver Transplantation in a Child with Kartagener Syndrome: A Case Report

Background

Kartagener syndrome (KS) is a rare genetic disorder consisting of the triad of situs inversus, chronic sinusitis, and bronchiectasis. Although there are previous reports regarding the anaesthetic considerations in KS, none have included liver transplantation.

Case Presentation

An 11-year-old boy with a diagnosis of KS underwent liver transplantation due to extrahepatic biliary atresia. Previous diagnostic imaging confirmed situs inversus and the absence of an inferior vena cava. The patient's peak airway pressure intermittently increased intraoperatively from 15 to 30 cm H₂O due to increased pulmonary secretions, which required frequent suctioning of the endotracheal tube. Intraoperative volume resuscitation included 200 mL of 5% albumin, 5 units of erythrocyte suspension and 3 units of fresh frozen plasma. Intermittently, a norepinephrine infusion was required to maintain the MAP. Coagulation function was monitoring using the thromboelastogram to guide the use of blood products including fresh frozen plasma. At the end of the surgery, the patient was transferred to the intensive care unit. He was discharged from the intensive care unit on postoperative day 5, and from the hospital on postoperative day 28. He continues to do well with normal liver function 23 months after surgery.

Conclusion

Despite the risk of pulmonary related to airway secretions and exacerbation of hemodynamic instability related to anatomical variations in the inferior vena cava anatomy, KS patients can be safely anesthetized with careful planning and attention of the disease process, even for complex surgical procedures such as liver transplantation.

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

Identification of a CCDC114 variant in a Han-Chinese patient with situs inversus

The function and position of the internal organs within the human body are based on left-right (LR) asymmetry. Human LR asymmetry disorders are characterized by abnormal LR asymmetric arrangement of the internal organs resulting from defective embryonic nodal cilia and nodal signaling pathway. The coiled-coil domain containing 114 gene (CCDC114) is related to the biogenesis of cilia and attachment of the outer dynein arms (ODAs) to the axoneme of cilia. Mutations in the CCDC114 gene are reported to cause a subtype of primary ciliary dyskinesia (PCD) named ciliary dyskinesia, primary, 20 (CILD20). Patients with CCDC114 mutations present with a type of ciliopathy with high clinical heterogeneity. In the present study, a Han-Chinese patient with situs inversus was recruited. Exome sequencing was performed on this patient combined with variant validation by Sanger sequencing. A homozygous variant c.584T>C (p.L195P) in the CCDC114 gene was identified as the likely genetic cause for situs inversus in this patient. The findings of our study extend the mutational spectrum of the CCDC114 gene, and contribute to clarifying the pathogenesis of human ciliopathies and benefit genetic counseling.

Health related quality of life in adult primary Ciliary dyskinesia patients in Cyprus: development and validation of the Greek version of the QOL-PCD questionnaire

BACKGROUND

The QOL-PCD questionnaire is a recently developed Health Related Quality of Life (HRQoL) instrument for Primary Ciliary Dyskinesia. The aim of this study was to translate the adult QOL-PCD questionnaire into Greek language and to conduct psychometric validation to assess its performance.

METHODS

Forward translations to Greek and backward translation to English were performed, followed by cognitive interviews in 12 adult PCD patients. The finalized translated version was administered to a consecutive sample of 31 adult, Greek speaking PCD patients in Cyprus for psychometric validation, which included assessment of internal consistency, test-retest reliability, construct and convergent validity. Internal consistency was assessed by Cronbach's alpha test in terms of the overall and sub-scales. Test-retest reliability was assessed by repeat administration of the questionnaire within 2 weeks and calculation of the intra-class correlation (ICC). Construct validity was assessed by comparing different groups of patients based on a-priori hypotheses and convergent validity was evaluated by examining associations between the QOL-PCD and SF-36 questionnaires.

RESULTS

Moderate to good internal consistency was observed (Cronbach's α: 0.46-0.88 across sub-scales) and test-retest reliability assessment demonstrated good repeatability for most scales (ICC: 0.67-0.91 across subscales). Patients of female gender, older age and lower lung function exhibited lower QOL-PCD scores in general, while high correlations for most QOL-PCD scales with corresponding SF-36 scales were observed, in particular for physical functioning (r = 0.78, p < 0.05).

CONCLUSION

The adult version of QoL-PCD questionnaire has been translated according to international guidelines resulting to a cross-culturally validated Greek version which exhibited moderate to good metric properties in terms of internal consistency, stability, known-group and convergent validity.

Ciliary functional analysis: Beating a path towards standardization

Primary ciliary dyskinesia is an inherited disorder in which respiratory cilia are stationary, or beat in a slow or dyskinetic manner, leading to impaired mucociliary clearance and significant sinopulmonary disease. One diagnostic test is ciliary functional analysis using digital high-speed video microscopy (DHSV), which allows real-time analysis of complete ciliary function, comprising ciliary beat frequency (CBF) and ciliary beat pattern (CBP). However, DHSV lacks standardization. In this paper, the current knowledge of DHSV ciliary functional analysis is presented, and recommendations given for a standardized protocol for ciliary sample collection and processing. A proposal is presented for a quantitative and qualitative CBP evaluation system, to be used to develop international consensus agreement, and future DHSV research areas are identified.

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.

Understanding the role of neutrophils in chronic inflammatory airway disease

Airway neutrophilia is a common feature of many chronic inflammatory lung diseases and is associated with disease progression, often regardless of the initiating cause. Neutrophils and their products are thought to be key mediators of the inflammatory changes in the airways of patients with chronic obstructive pulmonary disease (COPD) and have been shown to cause many of the pathological features associated with disease, including emphysema and mucus hypersecretion. Patients with COPD also have high rates of bacterial colonisation and recurrent infective exacerbations, suggesting that neutrophil host defence mechanisms are impaired, a concept supported by studies showing alterations to neutrophil migration, degranulation and reactive oxygen species production in cells isolated from patients with COPD. Although the role of neutrophils is best described in COPD, many of the pathological features of this disease are not unique to COPD and also feature in other chronic inflammatory airway diseases, including asthma, cystic fibrosis, alpha-1 anti-trypsin deficiency, and bronchiectasis. There is increasing evidence for immune cell dysfunction contributing to inflammation in many of these diseases, focusing interest on the neutrophil as a key driver of pulmonary inflammation and a potential therapeutic target than spans diseases. This review discusses the evidence for neutrophilic involvement in COPD and also considers their roles in alpha-1 anti-trypsin deficiency, bronchiectasis, asthma, and cystic fibrosis. We provide an in-depth assessment of the role of the neutrophil in each of these conditions, exploring recent advances in understanding, and finally discussing the possibility of common mechanisms across diseases.

Hearing loss in children with primary ciliary dyskinesia

OBJECTIVES

To evaluate the type and severity of hearing impairment in pediatric patients with primary ciliary dyskinesia (PCD) and relate these measures to patient demographics, treatment options, and other otologic factors.

METHODS

A retrospective analysis of children with a diagnosis of PCD, Kartagener's syndrome, or situs inversus in the AudGen Database was conducted. Audiograms were analyzed for type of hearing loss (HL), severity, laterality, and progression. Medical charts were reviewed to identify factors that influence severity and progression of hearing loss.

RESULTS

56 patients met inclusion criteria and 42 patients had HL. 66.6% had bilateral and 33.3% had unilateral loss (70 total ears with HL). Conductive hearing loss (CHL) was the most common type of HL, though 30% of children had some sensorineural component to their hearing loss. 92.9% of children with HL received at least one diagnosis of otitis media, but HL did not improve in the majority (77.8%) of ears in our study regardless of ear tube placement.

CONCLUSIONS

Slight to mild CHL and all types of otitis media are prevalent among patients with PCD, and some of these children have sensorineural hearing loss (SNHL). All patients diagnosed with situs inversus at birth should be evaluated by an otolaryngologist.

Chemoattractants and cytokines in primary ciliary dyskinesia and cystic fibrosis: key players in chronic respiratory diseases

Patients with primary ciliary dyskinesia (PCD) and cystic fibrosis (CF), two inherited disorders, suffer from recurrent airway infections characterized by persistent bacterial colonization and uncontrollable inflammation. Although present in high counts, neutrophils fail to clear infection in the airways. High levels of C-X-C motif chemokine ligand 8/interleukin-8 (CXCL8/IL-8), the most potent chemokine to attract neutrophils to sites of infection, are detected in the sputum of both patient groups and might cause the high neutrophil influx in the airways. Furthermore, in CF, airway neutrophils are highly activated because of the genetic defect and the high levels of proinflammatory chemoattractants and cytokines (e.g., CXCL8/IL-8, tumor necrosis factor-α and IL-17). The overactive state of neutrophils leads to lung damage and fuels the vicious circle of infection, excessive inflammation and tissue damage. The inflammatory process in CF airways is well characterized, whereas the lung pathology in PCD is far less studied. The knowledge of CF lung pathology could be useful to guide molecular investigations of the inflammatory processes in PCD lungs. Current available therapies can not completely remedy the chronic airway infections in these diseases. This review gives an overview of the role that chemoattractants and cytokines play in these neutrophil-dominated lung pathologies. Finally, the most frequently applied treatments in CF and PCD and new experimental therapies to reduce neutrophil-dominated airway inflammation are described.

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.

Neutrophils from Patients with Primary Ciliary Dyskinesia Display Reduced Chemotaxis to CXCR2 Ligands

Primary ciliary dyskinesia (PCD), cystic fibrosis (CF), and chronic obstructive airway disease are characterized by neutrophilic inflammation in the lungs. In CF and chronic obstructive airway disease, improper functioning of neutrophils has been demonstrated. We hypothesized that the pulmonary damage in PCD might be aggravated by abnormal functioning neutrophils either as a primary consequence of the PCD mutation or secondary to chronic inflammation. We analyzed chemotactic responses and chemoattractant receptor expression profiles of peripheral blood neutrophils from 36 patients with PCD, 21 healthy children and 19 healthy adults. We stimulated peripheral blood monocytes from patients and healthy controls and measured CXCL8 and IL-1β production with ELISA. PCD neutrophils displayed reduced migration toward CXCR2 ligands (CXCL5 and CXCL8) in the shape change, microchamber and microslide chemotaxis assays, whereas leukotriene B4 and complement component 5a chemotactic responses were not significantly different. The reduced response to CXCL8 was observed in all subgroups of patients with PCD (displaying either normal ultrastructure, dynein abnormalities or central pair deficiencies) and correlated with lung function. CXCR2 was downregulated in about 65% of the PCD patients, suggestive for additional mechanisms causing CXCR2 impairment. After treatment with the TLR ligands lipopolysaccharide and peptidoglycan, PCD monocytes produced more CXCL8 and IL-1β compared to controls. Moreover, PCD monocytes also responded stronger to IL-1β stimulation in terms of CXCL8 production. In conclusion, we revealed a potential link between CXCR2 and its ligand CXCL8 and the pathogenesis of PCD.

Clinical care for primary ciliary dyskinesia: current challenges and future directions

Primary ciliary dyskinesia (PCD) is a rare genetic disease that affects the motility of cilia, leading to impaired mucociliary clearance. It is estimated that the vast majority of patients with PCD have not been diagnosed as such, providing a major obstacle to delivering appropriate care. Challenges in diagnosing PCD include lack of disease-specific symptoms and absence of a single, “gold standard”, diagnostic test. Management of patients is currently not based on high-level evidence because research findings are mostly derived from small observational studies with limited follow-up period. In this review, we provide a critical overview of the available literature on clinical care for PCD patients, including recent advances. We identify barriers to PCD research and make suggestions for overcoming challenges.

Challenges in PCD must be overcome through international collaboration; networks must build on recent advanceshttp://ow.ly/4d4I30dXzWg

Prevalence of primary ciliary dyskinesia in consecutive referrals of suspect cases and the transmission electron microscopy detection rate: a systematic review and meta-analysis

Diagnostic testing for primary ciliary dyskinesia (PCD) usually includes transmission electron microscopy (TEM), nasal nitric oxide, high-speed video microscopy, and genetics. Diagnostic performance of each test should be assessed toward the development of PCD diagnostic algorithms. We systematically reviewed the literature and quantified PCD prevalence among referrals and TEM detection rate in confirmed PCD patients. Major electronic databases were searched until December 2015 using appropriate terms. Included studies described cohorts of consecutive PCD referrals in which PCD was confirmed by at least TEM and one additional test, in order to compare the index test performance with other test(s). Meta-analyses of pooled PCD prevalence and TEM detection rate across studies were performed. PCD prevalence among referrals was 32% (95% CI: 25-39%, I² = 92%). TEM detection rate among PCD patients was 83% (95% CI: 75-90%, I² = 90%). Exclusion of studies reporting isolated inner dynein arm defects as PCD, reduced TEM detection rate and explained an important fraction of observed heterogeneity (74%, 95% CI: 66-83%, I² = 66%). Approximately, one third of referrals, are diagnosed with PCD. Among PCD patients, a significant percentage, at least as high as 26%, is missed by TEM, a limitation that should be accounted toward the development of an efficacious PCD diagnostic algorithm.

Quality of Life Questionnaire for Turkish Patients with Primary Ciliary Dyskinesia

OBJECTIVES

Primary ciliary dyskinesia (PCD) is a major cause of progressive lung disease, and physiological measures do not reflect the impact of the disease on patients' daily symptoms or physical and social functions. We need valid and reliable health-related quality-of-life (HRQOL) measures in PCD to assess the symptoms and daily functions from the patient's perspective. Our aim was to develop a Turkish translation of PCD-specific HRQOL questionnairre to be used as outcomes in clinical trials.

MATERIAL AND METHODS

This study was conducted at the Division of Pediatric Pulmonology, Hacettepe University Faculty of Medicine and the Division of Pediatric Pulmonology, Marmara University Faculty of Medicine. Forward and back translations were performed by three different translators. We recruited participants with PCD from different age groups of both sexes, with an aim to represent a wide spectrum of disease severity and performed the prototype of the translation in these participants.

RESULTS

Five participants from each age group [children (6-12 years), teenagers (13-17 years), adults (18+ years) and parents of children aged from 6 to 12 years] responded to the HRQOL questionnaire. Content analysis of the questions included the following domains depending on age: Respiratory Symptoms, Physical Functioning, Emotional Functioning, Treatment Burden, Ears and Hearing, Sinus Symptoms, Social Functioning, Role Functioning, Vitality, Health Perceptions, School Functioning, Eating and Weight. After the participants have completed the questionnaire, a cognitive debriefing interview was conducted with them, and the results of the interviews were used to form a final version of PCD-specific HRQOL, ready for formal validation.

CONCLUSION

A Turkish translation of PCD-specific HRQOL questionnaire was developed to meet the standards set by international guidelines. This questionnaire is expected to be useful as end points in clinical trials for monitoring health outcomes and for improving clinical decisions.

Variation of Ciliary Beat Pattern in Three Different Beating Planes in Healthy Subjects

BACKGROUND

Digital high-speed video microscopy (DHSV) allows analysis of ciliary beat frequency (CBF) and ciliary beat pattern (CBP) of respiratory cilia in three planes. Normal reference data use a sideways edge to evaluate ciliary dyskinesia and calculate CBF using the time needed for a cilium to complete 10 beat cycles. Variability in CBF within the respiratory epithelium has been described, but data concerning variation of CBP is limited in healthy epithelium. This study aimed to document variability of CBP in normal samples, to compare ciliary function in three profiles, and to compare CBF calculated over five or 10 beat cycles.

METHODS

Nasal brushing samples from 13 healthy subjects were recorded using DHSV in three profiles. CBP and CBF over a 10-beat cycle were evaluated in all profiles, and CBF was reevaluated over five-beat cycles in the sideways edges.

RESULTS

A uniform CBP was seen in 82.1% of edges. In the sideways profile, uniformity within the edge was lower (uniform normal CBP, 69.1% [sideways profile]; 97.1% [toward the observer], 92.0% [from above]), and dyskinesia was higher. Interobserver agreement for dyskinesia was poor. CBF was not different between profiles (P = .8097) or between 10 and five beat cycles (P = .1126).

CONCLUSIONS

Our study demonstrates a lack of uniformity and consistency in manual CBP analysis of samples from healthy subjects, emphasizing the risk of automated CBP analysis in limited regions of interest and of single and limited manual CBP analysis. The toward the observer and from above profiles may be used to calculate CBF but may be less sensitive for evaluation of ciliary dyskinesia and CBP. CBF can be measured reliably by evaluation of only five-beat cycles.

Gmnc Is a Master Regulator of the Multiciliated Cell Differentiation Program

Multiciliated cells (MCCs) differentiate hundreds of motile cilia that generate mechanical force required to drive fluid movement over epithelia [1, 2]. For example, metachronal beating of MCC cilia in the mammalian airways clears mucus that traps inhaled pathogens and pollutants. Consequently, abnormalities in MCC differentiation or ciliary motility have been linked to an expanding spectrum of human airway diseases [3–6]. The current view posits that MCC precursors are singled out by the inhibition of Notch signaling. MCC precursors then support an explosive production of basal bodies, which migrate to the apical surface, dock with the plasma membrane, and seed the growth of multiple motile cilia. At the center of this elaborate differentiation program resides the coiled-coil-containing protein Multicilin, which transcriptionally activates genes for basal body production and the gene for FoxJ1, the master regulator for basal body docking, cilia formation, and motility [7, 8]. Here, using genetic analysis in the zebrafish embryo, we discovered that Gmnc is a novel determinant of the MCC fate. Like Multicilin, Gmnc is a coiled-coil-containing protein of the Geminin family. We show that Gmnc functions downstream of Notch signaling, but upstream of Multicilin in the developmental pathway controlling MCC specification. Moreover, we find that loss of Gmnc in Xenopus embryos also causes loss of MCC differentiation and that overexpression of the protein is sufficient to induce supernumerary MCCs. Together, our data identify Gmnc as an evolutionarily conserved master regulator functioning at the top of the hierarchy of transcription factors involved in MCC differentiation.

Chibby functions to preserve normal ciliary morphology through the regulation of intraflagellar transport in airway ciliated cells

Airway cilia provide the coordinated motive force for mucociliary transport, which prevents the accumulation of mucus, debris, pollutants, and bacteria in our respiratory tracts. As airway cilia are constantly exposed to the environment and, hence, are an integral component of the pathogenesis of several congenital and chronic pulmonary disorders, it is necessary to understand the molecular mechanisms that control ciliated cell differentiation and ciliogenesis. We have previously reported that loss of the basal body protein Chibby (Cby) results in chronic upper airway infection in mice due to a significant reduction in the number of airway cilia. In the present work, we demonstrate that Cby is required for normal ciliary structure and proper distribution of proteins involved in the bidirectional intraflagellar transport (IFT) system, which consists of 2 distinct sub-complexes, IFT-A and IFT-B, and is essential for ciliary biogenesis and maintenance. In fully differentiated ciliated cells, abnormal paddle-like cilia with dilated ciliary tips are observed in Cby-/- airways and primary cultures of mouse tracheal epithelial cells (MTECs). In addition, IFT88, an IFT-B sub-complex protein, robustly accumulates within the dilated tips of both multicilia in Cby-/- MTECs and primary cilia in Cby-/- mouse embryonic fibroblasts (MEFs). Furthermore, we show that only IFT-B components, including IFT20 and IFT57, but not IFT-A and Bardet-Biedl syndrome (BBS) proteins, amass with IFT88 in these distended tips in Cby-/- ciliated cells. Taken together, our findings suggest that Cby plays a role in the proper distribution of IFT particles to preserve normal ciliary morphology in airway ciliated cells.

Clinical manifestations in primary ciliary dyskinesia: systematic review and meta-analysis

Few original studies have described the prevalence and severity of clinical symptoms of primary ciliary dyskinesia (PCD). This systematic review and meta-analysis aimed to identify all published studies on clinical manifestations of PCD patients, and to describe their prevalence and severity stratified by age and sex.We searched PubMed, Embase and Scopus for studies describing clinical symptoms of ≥10 patients with PCD. We performed meta-analyses and meta-regression to explain heterogeneity.We included 52 studies describing a total of 1970 patients (range 10-168 per study). We found a prevalence of 5% for congenital heart disease. For the rest of reported characteristics, we found considerable heterogeneity (I² range 68-93.8%) when calculating the weighted mean prevalence. Even after taking into account the explanatory factors, the largest part of the between-studies variance in symptom prevalence remained unexplained for all symptoms. Sensitivity analysis including only studies with test-proven diagnosis showed similar results in prevalence and heterogeneity.Large differences in study design, selection of study populations and definition of symptoms could explain the heterogeneity in symptom prevalence. To better characterise the disease, we need larger, multicentre, multidisciplinary, prospective studies that include all age groups, use uniform diagnostics and report on all symptoms.

An effective combination of sanger and next generation sequencing in diagnostics of primary ciliary dyskinesia

BACKGROUND

Primary ciliary dyskinesia (PCD) is a multigenic autosomal recessive condition affecting respiratory tract and other organs where ciliary motility is required. The extent of its genetic heterogeneity is remarkable. The aim of the study was to develop a cost-effective pipeline for genetic diagnostics using a combination of Sanger and next generation sequencing (NGS).

MATERIALS AND METHODS

Data and samples of 33 families with 38 affected subjects with PCD diagnosed in childhood were collected over the territory of the Czech Republic. A panel of 18 PCD causative or candidate genes was implemented into an Illumina TruSeq Custom Amplicon NGS assay, and three ancestral mutations in SPAG1 were screened by conventional Sanger sequencing, which was also used for the confirmation of the NGS results and for the analysis of familial segregation.

RESULTS

The causative gene was DNAH5 in 11/33 (33%) probands, SPAG1 in 8/33 (24%), and DNAI1, CCDC40, LRRC6 in one family each. If the high proportion of subjects with bi-allelic ancestral mutations in SPAG1 is corroborated in other Caucasian populations, a simple Sanger sequencing test for these three mutations may serve as an effective pre-screening step, being followed by an NGS panel for other, much larger, PCD genes.

CONCLUSIONS

We present a combination of Sanger sequencing with an NGS panel for known and candidate PCD genes, implemented in a moderate-size national collection of patients. This strategy has proven to be cost-effective, rapid and reliable, and was able to detect the causative gene in two thirds of our PCD patients.

Left middle lobectomy for bronchiectasis in a patient with Kartagener syndrome: a case report

Background

Kartagener syndrome (KS) is a rare disorder characterized by the triad of chronic sinusitis, bronchiectasis, and situs inversus.

Case presentation

A 23-year-old man was admitted to our hospital because of recurrent cough with purulent expectoration, which had occurred intermittently for the past ten years. During the past 3 years, the episode frequency was 3–4 times per year. He was diagnosed with pulmonary infection and bronchiectasis of the left upper lobe, situs inversus, and KS. We concluded that the damaged left middle lobe was the source of repeat pulmonary infections. Thus the left middle lobe resection was performed to remove the source of the lung infection.

Conclusions

The post-operative course was successful and pneumonia was apparently resolved during the 6 months’ follow-up period. We further describe this case in the following report.

Clinical spectrum of primary ciliary dyskinesia in childhood

Although the triad of bronchiectasis, sinusitis and situs inversus was first described by Kartagener in 1933, the clinical spectrum of primary ciliary dyskinesia is still under investigation. Heterotaxy defects as well as upper and lower respiratory tract symptoms are the main manifestations in childhood. It is now recognized that situs inversus is encountered in only half of patients. The first lower respiratory symptoms may be present from infancy as neonatal respiratory distress. The most common lower airway manifestations are chronic wet cough, recurrent pneumonia and therapy resistant wheezing. Patients are at risk of developing bronchiectasis which may even be the presenting finding due to delayed diagnosis. Upper respiratory tract infections such as nasal congestion, nasal drainage and recurrent sinusitis as well as otologic manifestations such as otitis media or otorrhea with conductive hearing loss are also often encountered. It seems that the type of ciliary ultrastructure defects and the involved mutated genes are associated to some extent to the clinical profile. The disease, even in nowadays, is not recognized at an early age and the primary care clinician should have knowledge of its clinical spectrum in order to select appropriately the children who need further investigation for the diagnosis of this disorder.

Diagnosis, monitoring, and treatment of primary ciliary dyskinesia: PCD foundation consensus recommendations based on state of the art review

Primary ciliary dyskinesia (PCD) is a genetically heterogeneous, rare lung disease resulting in chronic oto-sino-pulmonary disease in both children and adults. Many physicians incorrectly diagnose PCD or eliminate PCD from their differential diagnosis due to inexperience with diagnostic testing methods. Thus far, all therapies used for PCD are unproven through large clinical trials. This review article outlines consensus recommendations from PCD physicians in North America who have been engaged in a PCD centered research consortium for the last 10 years. These recommendations have been adopted by the governing board of the PCD Foundation to provide guidance for PCD clinical centers for diagnostic testing, monitoring, and appropriate short and long-term therapeutics in PCD patients.

Diagnosis of primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a genetic disorder of ciliary structure or function. It results in mucus accumulation and bacterial colonization of the respiratory tract which leads to chronic upper and lower airway infections, organ laterality defects, and fertility problems. We review the respiratory signs and symptoms of PCD, as well as the screening tests for and diagnostic investigation of the disease, together with details related to ciliary function, ciliary ultrastructure, and genetic studies. In addition, we describe the difficulties in diagnosing PCD by means of transmission electron microscopy, as well as describing patient follow-up procedures.

Orphan diseases of the nose and paranasal sinuses: Pathogenesis - clinic - therapy

Rare rhinological diseases are a diagnostic challenge. Sometimes it takes months or even years from the primary manifestation of the disease until the definitive diagnosis is establibshed. During these times the disease proceeds in an uncontrolled or insufficiently treated way. (Irreversible) damage results and sometimes life-threatening situations occur. The unexpected course of a (misdiagnosed) disease should lead to further diagnostic reflections and steps in order to detect also rare diseases as early as possible. The present paper discusses granulomatous diseases of the nose and paranasal sinuses caused by mycobacteria, treponema, Klebsiella, fungi, and protozoa as well as vasculitis, sarcoidosis, rosacea, cocaine-induced midline destruction, nasal extranodal NK/T cell lymphoma, and cholesterol granuloma. Furthermore, diseases with disorders of the mucociliary clearance such as primary ciliary dyskinesia and cystic fibrosis are presented, taking into consideration the current literature.

Diagnostic accuracy of nasal nitric oxide for establishing diagnosis of primary ciliary dyskinesia: a meta-analysis

BACKGROUND

To date, diagnosis of Primary Ciliary Dyskinesia (PCD) remains difficult and challenging. We systematically evaluated the diagnostic performance of nasal Nitric Oxide (nNO) measurement for the detection of PCD, using either velum-closure (VC) or non-velum-closure (non-VC) techniques.

METHODS

All major electronic databases were searched from inception until March 2015 using appropriate terms. The sensitivity and specificity of nNO measurement was calculated in PCD patients diagnosed by transmission electron microscopy, high speed video-microscopy or genetic testing. Summary receiver operating characteristic (HSROC) curves were drawn using the parameters of the fitted models.

RESULTS

Twelve studies provided data for 13 different populations, including nine case-control (n = 793) and four prospective cohorts (n = 392). The overall sensitivity of nNO measured by VC techniques was 0.95 (95 % CI 0.91-0.97), while specificity was 0.94 (95 % CI 0.88-0.97). The positive likelihood ratio (LR+) of the test was 15.8 (95 % CI 8.1-30.6), whereas the negative likelihood ratio (LR-) was 0.06 (95 % CI 0.04-0.09). For non-VC techniques, the overall sensitivity of nNO measurement was 0.93 (95 % CI 0.89-0.96) whereas specificity was 0.95 (95 % CI 0.82-0.99). The LR+ of the test was 18.5 (95 % CI 4.6-73.8) whereas the LR- was 0.07 (95 % CI 0.04-0.12).

CONCLUSIONS

Diagnostic accuracy of nNO measurement both with VC and non-VC maneuvers is high and can be effectively employed in the clinical setting to detect PCD even in young children, thus potentiating early diagnosis. Measurement of nNO merits to be part of a revised diagnostic algorithm with the most efficacious combination of tests to achieve PCD diagnosis.

Decreased Levels of Nasal Nitric Oxide in Children With Midline Neuroanatomical Anomalies: A Possible Connection Between Ciliary Dysfunction and Isolated Nervous System Defects

OBJECTIVES

Given the involvement of cilia in midline neurodevelopment, we set to determine whether children with midline neuroanatomical defects have increased prevalence of ciliary dysfunction, using nasal nitric oxide measurement, a screening test for primary ciliary dyskinesia.

STUDY DESIGN

We measured the nasal nitric oxide levels of 26 children ages 6-17, with congenital midline central nervous system defects, who are otherwise healthy. We evaluated the effect of variables including: age, gender, and anomaly (brain, spinal cord, or combined) on our measurements. We compared our results with the previously established normal range (153.6-509.9 nL/min) and to the cutoff for children with primary ciliary dyskinesia (77 nL/min).

RESULTS

The overall range for nasal nitric oxide in our cohort was 56.5-334.7 nL/min, with age, gender, and anomaly not having a significant effect. The overall mean, 217.7 nL/min, was significantly lower than the preestablished mean in normal children, 314.51 nL/min (P < 0.01). Four patients (15.4%) had nitric oxide levels below the lower end of normal, with two (7.7%) having values below the cutoff for primary ciliary dyskinesia.

CONCLUSIONS

This is the first study to report a possible association between ciliary dysfunction and isolated congenital midline neuroanatomical defects, not in the context of any known syndrome. We suggest that genes known to cause isolated central nervous system defects may also be involved in the function of cilia. Longitudinal studies are required to investigate whether, in children with abnormal measurements, nasal nitric oxide levels normalize over time, and whether these children suffer from any respiratory sequelae.

Successful treatment of chronic lower respiratory tract infection by macrolide administration in a patient with intralobar pulmonary sequestration and primary ciliary dyskinesia

Primary ciliary dyskinesia (PCD) is a genetic disease associated with abnormalities in ciliary structure and function. Although recurrent respiratory infection associated with ciliary dysfunction is a common clinical feature, there is no standardized treatment or management of respiratory infection in PCD patients. Here, we report that respiratory infection with PCD and intralobar sequestration (ILS) were treated successfully with clarithromycin before the surgical resection of ILS. A 15-year-old non-smoking Japanese woman was admitted for productive cough and dyspnea on exertion. Chest CT scan on admission showed complex cystic LESIONS with air-fluid level in the right lower lobe, and diffuse nodular shadows in the whole lobe of the lung. On flexible bronchoscopy examination, sputum and bronchiolar fluid cultures revealed Staphylococcus aureus (S. aureus). An electron microscopic examination of the cilia showed inner dynein arm deficiency. Administration of clarithromycin improved the lower respiratory tract infection associated with S. aureus. CT angiography after clarithromycin treatment demonstrated an aberrant systemic artery arising from the celiac trunk and supplying the cystic mass lesions that were incorporated into the normal pulmonary parenchyma without their own pleural covering. Based on these results, the patient was diagnosed with PCD and ILS. Because of the clarithromycin treatment, resection of the ILS was performed safely without any complications. Although further observation of clarithromycin treatment is needed, we believe that clarithromycin may be considered one of the agents for treating PCD.

Presentation of primary ciliary dyskinesia in children: 30 years' experience

AIM

Primary ciliary dyskinesia (PCD) is a rare (1:15,000) condition resulting in recurrent suppurative respiratory tract infections, progressive lung damage and hearing impairment. As the diagnosis is often delayed for years, the purpose of this study was to review the presenting features of children with PCD attending Australia's initial diagnostic PCD service over a 30-year period.

METHOD

A retrospective review of the symptoms of children diagnosed with PCD at Concord Hospital between 1982 and 2012 was undertaken.

RESULTS

One thousand thirty-seven paediatric patients were referred for assessment and underwent nasal ciliary brushing. Eighty-four (8.1%) had PCD based on microscopic analysis of nasal cilia. This included 81 with ciliary ultrastructural abnormalities demonstrated on electron microscopy and 3 with a suggestive phenotype, reduced ciliary beat frequency and a family history of PCD. The median age at diagnosis was 6.4 years (range 0.1 to 18.2 years). Forty-six per cent had situs abnormalities and 31% had a family member with PCD. Recurrent cough (81%), rhinosinusitis (71%), recurrent otitis media (49%) and neonatal respiratory distress (57%) were reported. Bronchiectasis at presentation was documented in 32%. Situs abnormalities and neonatal respiratory distress were present together in 26%.

CONCLUSION

PCD remains under-recognised by health-care workers. The combination of neonatal respiratory distress, chronic suppurative cough and rhinosinusitis was the most common documented symptom cluster at presentation in cases of PCD. A heightened awareness of the clinical features of the disease may help to lower the age at diagnosis, facilitate appropriate treatment and improve long-term outcomes.

Teratozoospermia: spotlight on the main genetic actors in the human

BACKGROUND

Male infertility affects >20 million men worldwide and represents a major health concern. Although multifactorial, male infertility has a strong genetic basis which has so far not been extensively studied. Recent studies of consanguineous families and of small cohorts of phenotypically homogeneous patients have however allowed the identification of a number of autosomal recessive causes of teratozoospermia. Homozygous mutations of aurora kinase C (AURKC) were first described to be responsible for most cases of macrozoospermia. Other genes defects have later been identified in spermatogenesis associated 16 (SPATA16) and dpy-19-like 2 (DPY19L2) in patients with globozoospermia and more recently in dynein, axonemal, heavy chain 1 (DNAH1) in a heterogeneous group of patients presenting with flagellar abnormalities previously described as dysplasia of the fibrous sheath or short/stump tail syndromes, which we propose to call multiple morphological abnormalities of the flagella (MMAF).

METHODS

A comprehensive review of the scientific literature available in PubMed/Medline was conducted for studies on human genetics, experimental models and physiopathology related to teratozoospermia in particular globozoospermia, large headed spermatozoa and flagellar abnormalities. The search included all articles with an English abstract available online before September 2014.

RESULTS

Molecular studies of numerous unrelated patients with globozoospermia and large-headed spermatozoa confirmed that mutations in DPY19L2 and AURKC are mainly responsible for their respective pathological phenotype. In globozoospermia, the deletion of the totality of the DPY19L2 gene represents ∼ 81% of the pathological alleles but point mutations affecting the protein function have also been described. In macrozoospermia only two recurrent mutations were identified in AURKC, accounting for almost all the pathological alleles, raising the possibility of a putative positive selection of heterozygous individuals. The recent identification of DNAH1 mutations in a proportion of patients with MMAF is promising but emphasizes that this phenotype is genetically heterogeneous. Moreover, the identification of mutations in a dynein strengthens the emerging point of view that MMAF may be a phenotypic variation of the classical forms of primary ciliary dyskinesia. Based on data from human and animal models, the MMAF phenotype seems to be favored by defects directly or indirectly affecting the central pair of axonemal microtubules of the sperm flagella.

CONCLUSIONS

The studies described here provide valuable information regarding the genetic and molecular defects causing infertility, to improve our understanding of the physiopathology of teratozoospermia while giving a detailed characterization of specific features of spermatogenesis. Furthermore, these findings have a significant influence on the diagnostic strategy for teratozoospermic patients allowing the clinician to provide the patient with informed genetic counseling, to adopt the best course of treatment and to develop personalized medicine directly targeting the defective gene products.

Mutation analysis in patients with total sperm immotility

PURPOSE

Perform the genetic characterization of five patients with total sperm immotility using Sanger sequencing and Whole Exome Sequencing (WES), in order to increase the knowledge on the genetics of sperm immotility and, ultimately, allow the identification of potential genetic markers for infertility.

METHODS

Prospective study at a University Medical school. We analysed five men with total sperm immotility, four with dysplasia of the fibrous sheath (DFS), associated with disruption of several axonemal structures, and one patient with situs inversus totalis, which showed absence of dynein arms (DA) and nexin bridges. We screened 7 genes by Sanger sequencing, involved in sperm motility and associated to ultrastructural defects found in these patients (CCDC39, CCDC40, DNAH5, DNAI1, RSPH1, AKAP3 and AKAP4). Additionally, we performed WES analysis in the patient with situs inversus.

RESULTS

We identified nine new DNA sequence variants by WES. Two of these variants were considered particularly relevant: a homozygous missense change in CCDC103 gene (c.104G > C, p.R35P) probably related with absence of dynein arms; the other in the INSL6 gene (c.262_263delCC) is thought to be also involved in sperm immotility.

CONCLUSIONS

Our work suggests that WES is an effective strategy, especially as compared with conventional sequencing, to study highly heterogenic genetic diseases, such as sperm immotility. For future work we expect to expand the analysis of WES to the other four patients and complement findings with expression analysis or functional studies to determine the impact of the novel variants.

Clinical analysis of patients with primary ciliary dyskinesia in mainland China

BACKGROUND AND AIMS

Primary ciliary dyskinesia (PCD) is a rare, genetic disorder featured with dysfunctional motility of cilia. Clinical presentations of PCD include situs inversus, repeated respiratory tract infections, otitis media, sinusitis and infertility. This study aims to provide clinical strategies on diagnosis and treatment of PCD.

METHODS

Clinical data of seven patients diagnosed as PCD in Zhongshan Hospital, Fudan University were analyzed. We also extracted data from other cases in mainland China from the China Academic Journals Full-Text Database by the end of 2012. A total of 127 cases of PCD were summarized and analyzed in this study.

RESULTS

Seven patients in Zhongshan Hospital, Fudan University were finally confirmed to have PCD. All of them had clinical history of recurrent respiratory infection. Imaging analysis showed varying degrees of bronchiectasis. Pulmonary function tests in four patients showed combined obstructive and restrictive patterns. Three cases were confirmed to have PCD by electron microscopy. We then further extracted information from literature for those 127 PCD patients in mainland China. All of them had chronic respiratory infection. Seven cases were complicated with recurrent otitis media and 15 cases were complicated with infertility. A total of 119 patients were diagnosed with situs inversus totalis (94%). Among those 127 patients, only 9 patients' diagnosis was confirmed by electron microscopy. Four patients received sinus resection, and one patient received pulmonary lobectomy due to recurrent hemoptysis. One patient died of massive hemoptysis.

CONCLUSIONS

Being a rare disease and easily confused with uncomplicated bronchiectasis, PCD diagnosis warrants particular attention. Recurrent respiratory infection, especially situs inversus could be the most important indicator of this disease.

Variation in DNAH1 may contribute to primary ciliary dyskinesia

BACKGROUND

Primary Ciliary Dyskinesia (PCD) is a genetically heterogeneous ciliopathy caused by ultrastructural defects in ciliary or flagellar structure and is characterized by a number of clinical symptoms including recurrent respiratory infections progressing to permanent lung damage and infertility.

CASE PRESENTATION

Here we describe our search to delineate the molecular basis in two affected sisters with clinically diagnosed PCD from a consanguineous Saudi Arabian family, in which all known genes have been excluded. A homozygosity mapping-based approach was utilized that ultimately identified one single affected-shared region of homozygosity using 10 additional unaffected family members. A plausible candidate gene was directly sequenced and analyzed for mutations. A novel homozygous missense aberration (p.Lys1154Gln) was identified in both sisters in the DNAH1 gene that segregated completely with the disease phenotype. Further confirmation of this interesting variant was provided by exome-wide analysis in the proband.

CONCLUSION

Molecular variation in DNAH1 may play a role in PCD and its potential contribution should be considered in patients where all known genes are excluded.

Lung structure-function correlation in patients with primary ciliary dyskinesia

BACKGROUND

Primary ciliary dyskinesia (PCD) is a rare disease, characterised by chronic airway infection. In cystic fibrosis, FEV1 is insensitive to detect patients with structural damage, and Lung Clearance Index (LCI) was proposed as a better marker of early lung damage. In PCD, the relationship between functional and structural abnormalities has been less studied. We aimed to re-examine this in a cohort of children and adults with mild to moderate PCD.

METHODS

Thirty-eight patients with PCD (5.2-25.0 years) and 70 healthy controls (4.4-25.8 years) were recruited to compare LCI, measured by N2 multiple breath washout and FEV1 in a prospective observational trial. In a subset of 30 patients who underwent chest imaging, structural abnormalities were evaluated with cystic fibrosis computed tomography (CFCT) scores.

RESULTS

LCI was abnormal in 28 of 38 patients and a moderate correlation was observed between LCI and FEV1 (r=-0.519, p=0.001). Moreover, LCI correlated well with CFCT total score (r=0.800, p<0.001) and also with subscores for airway wall thickening (r=0.809, p<0.001), mucus plugging (r=0.720, p<0.001) and bronchiectasis (r=0.494, p<0.001). Concordance was seen between LCI and CFCT in 25 of 30 (83%) patients, but between FEV1 and CFCT in only 16 of 30 (53%) patients. LCI was more sensitive (90.9%, 95% CI 70.8 to 98.6) to detect patients with structural abnormalities than FEV1 (36.4%, 95% CI 17.2 to 59.3).

CONCLUSIONS

We demonstrated that measuring LCI in patients with PCD is of clinical relevance; it was more frequently abnormal than FEV1, correlated well with CFCT and was more sensitive than FEV1 to detect patients with structural abnormalities.

Pulmonary epithelial barrier function: some new players and mechanisms

The pulmonary epithelium serves as a barrier to prevent access of the inspired luminal contents to the subepithelium. In addition, the epithelium dictates the initial responses of the lung to both infectious and noninfectious stimuli. One mechanism by which the epithelium does this is by coordinating transport of diffusible molecules across the epithelial barrier, both through the cell and between cells. In this review, we will discuss a few emerging paradigms of permeability changes through altered ion transport and paracellular regulation by which the epithelium gates its response to potentially detrimental luminal stimuli. This review is a summary of talks presented during a symposium in Experimental Biology geared toward novel and less recognized methods of epithelial barrier regulation. First, we will discuss mechanisms of dynamic regulation of cell-cell contacts in the context of repetitive exposure to inhaled infectious and noninfectious insults. In the second section, we will briefly discuss mechanisms of transcellular ion homeostasis specifically focused on the role of claudins and paracellular ion-channel regulation in chronic barrier dysfunction. In the next section, we will address transcellular ion transport and highlight the role of Trek-1 in epithelial responses to lung injury. In the final section, we will outline the role of epithelial growth receptor in barrier regulation in baseline, acute lung injury, and airway disease. We will then end with a summary of mechanisms of epithelial control as well as discuss emerging paradigms of the epithelium role in shifting between a structural element that maintains tight cell-cell adhesion to a cell that initiates and participates in immune responses.

Community-acquired pneumonia

PURPOSE OF REVIEW

This review examines the epidemiology, diagnosis, prognosis, treatment and prevention of community-acquired pneumonia (CAP) in adults.

RECENT FINDINGS

CAP is a significant cause of morbidity and mortality. Streptococcus pneumoniae is the most common CAP pathogen; however, microbial cause varies by geographic location and host factors. Identification of a microbial cause in CAP remains challenging - 30-65% of cases do not have a pathogen isolated. The use of molecular techniques in addition to culture, serology and urinary antigen testing has improved diagnostic yield. Scoring systems are useful for CAP prognostication and site of care decisions. Studies evaluating novel biomarkers including pro-B-type natriuretic peptide and procalcitonin suggest potential adjunctive roles in CAP prognosis. Guideline-based treatment for CAP has changed little in recent years. Effective and timely antimicrobial therapy is crucial in optimizing outcomes and should be based on local antimicrobial susceptibility patterns. Macrolides may have additional anti-inflammatory properties and a mortality benefit in severe CAP. Preventive strategies include immunization and modification of specific patient risk factors.

SUMMARY

CAP is common and causes considerable morbidity and mortality. A comprehensive approach including advanced diagnostic testing, effective and timely antimicrobial therapy and prevention is required to optimize CAP outcomes.