Transmission electron microscopy in the diagnosis of primary ciliary dyskinesia

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.

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

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

Live birth after Laser Assisted Viability Assessment (LAVA) to detect pentoxifylline resistant ejaculated immotile spermatozoa during ICSI in a couple with male Kartagener's syndrome

Primary ciliary dyskinesia (PCD) is a rare, autosomal recessive disease with abnormalities in the structure of cilia, causing impairment of muco-ciliary clearance with respiratory tract infections, heterotaxia and abnormal sperm motility with male infertility. Here, with a comprehensive literature review, we report a couple with an infertility history of 9 years and three unsuccessful IVF treatments, where male partner has Kartagener's Syndrome, a subtype of PCD, displaying recurrent respiratory infections, dextrocardia and total asthenozoospermia. His diagnosis was verified with transmission electron microscopy and genetic mutation screening, revealing total absence of dynein arms in sperm tails and homozygous mutation in the ZMYND10, heterozygous mutations in the ARMC4 and DNAH5 genes. Laser assisted viability assay (LAVA) was performed by shooting the sperm tails during sperm retrieval for microinjection, following detection of pentoxifylline resistant immotile sperm. Live births of healthy triplets, one boy and two monozygotic girls, was achieved after double blastocyst transfer.

Ciliary ultrastructure in patients with chronic rhinosinusitis and primary ciliary dyskinesia

The Cilia represent one of the main mechanisms contributing to the clearance of microorganisms and particles from the respiratory epithelium. Primary ciliary dyskinesia (PCD) is a genetically determined disorder characterized by irreversible systemic dysmotility of the cilia. Secondary ciliary dyskinesia (SCD) differs from primary defects on the reversible ultrastructural alterations that can occur after any insult to a previously normal mucosa. Hence, this study aimed to describe and compare the main ultrastructural ciliary features in PCD and SCD through transmission electron microscopy. The most frequent PCD abnormalities were missing or short dynein arms, missing central microtubules, and displacement of one of the nine peripheral doublets. The most common changes found in SCD were compound cilia and peripheral microtubule alterations associated with modifications of the respiratory epithelium. PCD presented a higher percentage of altered cilia (>30 %) when compared to SCD (5 %), demonstrating that SCD is more limited in area than PCD. Whereas in PCD the changes in the dynein arms and in the central microtubules are fundamental for diagnostic confirmation, the diagnosis of SCD usually involves compound cilia and disarrangements in peripheral microtubules.

Light, polarizing, and transmission electron microscopy: three methods for the evaluation of sperm quality

Semen from 33 patients were evaluated by light microscopy (LM) obtaining sperm concentration, percent motility, percentage of sperm with normal morphology (PAP staining), and percentage of dead sperm (Eosin Y stained). The samples were observed by polarizing microscopy (PM), that evaluates sperm morphology and the viability by birefringence of organelles, and it provides a PM index (percentage of birefringent, viable, motile sperm) and a percentage of dead, non-birefringent sperm. Sperm were processed for transmission electron microscopy (TEM) and TEM data were elaborated with a mathematical formula able to provide a fertility index (FI, number of sperm free of structural defects) and percentages of sperm immaturity and necrosis (dead sperm). To test the reliability of these techniques, the values of normal acrosome, nucleus, midpiece, and tail and the presence of cytoplasmic residues obtained with the three methods were compared. With the exception of cytoplasmic residues (P = 0.40), significant differences in the evaluation of each organelle were observed and TEM analysis resulted as the most stringent screening. In addition, relationships among relevant sperm variables were investigated. Motility showed positive correlations with the percentage of normal tail, midpiece, and PM index (P < 0.01), but it exhibited negative correlations with indices of sperm death (non-birefringent sperm: P < 0.05; percentage of eosin Y stained sperm: P < 0.05; necrosis: P < 0.01), which were positively correlated with each other (P < 0.01). Positive correlations were found between indices expressing normal sperm morphology: FI with PM index (P < 0.01) and with the percentage of normal sperm (PAP staining) (P < 0.01), which in turn were correlated with the PM index (P < 0.001). Sperm immaturity showed positive correlations (P < 0.01) with the presence of cytoplasmic residues detected with the three methods. In conclusion, LM, PM, and TEM are reliable techniques in evaluating sperm quality. PM appears to offer several advantages 'midway' between LM and TEM and it should be considered in sperm analysis.

Otitis media in a new mouse model for CHARGE syndrome with a deletion in the Chd7 gene

Otitis media is a middle ear disease common in children under three years old. Otitis media can occur in normal individuals with no other symptoms or syndromes, but it is often seen in individuals clinically diagnosed with genetic diseases such as CHARGE syndrome, a complex genetic disease caused by mutation in the Chd7 gene and characterized by multiple birth defects. Although otitis media is common in human CHARGE syndrome patients, it has not been reported in mouse models of CHARGE syndrome. In this study, we report a mouse model with a spontaneous deletion mutation in the Chd7 gene and with chronic otitis media of early onset age accompanied by hearing loss. These mice also exhibit morphological alteration in the Eustachian tubes, dysregulation of epithelial proliferation, and decreased density of middle ear cilia. Gene expression profiling revealed up-regulation of Muc5ac, Muc5b and Tgf-β1 transcripts, the products of which are involved in mucin production and TGF pathway regulation. This is the first mouse model of CHARGE syndrome reported to show otitis media with effusion and it will be valuable for studying the etiology of otitis media and other symptoms in CHARGE syndrome.

[Primary ciliary dyskinesia: a retrospective review of clinical and paraclinical data]

INTRODUCTION

Primary ciliary dyskinesia (PCD) is an inherited disease responsible for a disruption of normal ciliary function. Its clinical presentation is usually in early childhood with pulmonary and otorhinolaryngologic symptoms. Early diagnosis is essential to avoid the development of bronchiectasis. The aim of the study was to retrospectively review the clinical features of children suspected to have PCD.

RESULTS

A total of 89 children had a bronchoscopy to perform a biopsy analyzed by transmission electron microscopy (TEM) in the childrens' hospital of Rennes between 2000 and 2009. PCD was diagnosed in 17 children, excluded in 51 and results were uncertain in 21 children. Mean age at diagnosis was 6.5 years. In the PCD group, a history of neonatal respiratory distress was found in 40% of cases, 82% had had bronchopneumonia, 37% sinusitis, 82% recurrent otitis and 23% situs inversus. These subjects had defects in ciliary structure, 59% in the dynein arms, 35% in the central complex and 6% having both. Nasal nitric oxide production was consistent with the results of TEM in 16 cases: five PCD, 11 without PCD. In two cases, the results were discordant.

CONCLUSION

This case series highlights the key clinical features of recurrent otitis, sinusitis, and situs inversus, especially when occurring in combination with bronchitic symptoms. Measures of nasal nitric oxide are useful for the diagnosis of PCD and in the case of high levels of NO, PCD is unlikely. Results may not be definitive and TEM analysis of biopsies is still indispensable to ensure the diagnosis and guide genetic counselling.

ENT manifestations in patients with primary ciliary dyskinesia: prevalence and significance of otorhinolaryngologic co-morbidities

Primary ciliary dyskinesia (PCD) is a rare inherited disease with a prevalence of about 1:20,000. The underlying pathogenesis is disrupted ciliary function, which results in delayed mucus transportation leading to chronic inflammation, mainly in the upper and lower respiratory tract. Although the pathogenesis of the disease and its clinical presentation is somewhat understood, data regarding the prevalence of accompanying symptoms is limited, especially in the field of otorhinolaryngology. A total of 44 patients diagnosed with PCD answered a questionnaire regarding the diagnosis and clinical presentation of the disease, their medical history and clinical manifestations, and medical treatment in the field of otorhinolaryngology. The majority of participants (70%) had seen a physician more than 50 times before the diagnosis was made at an average age of 10.9 ± 14.4 years. As much as 59% of all patients had recurring problems at the paranasal sinuses and 69% of these patients needed corresponding surgical intervention. Even more patients (81%) suffered from recurring otitis media and, as a result, 78% of these patients underwent paracentesis with temporary tympanostomy tubes at least once at an average age of 9.5 ± 13.0 years. Otorhinolaryngologic symptoms, especially chronic otitis media and chronic rhinosinusitis, are frequently associated with PCD. Surgical intervention to treat these symptoms is common. The awareness of this disease should be raised, especially among ENT physicians, and surgical intervention should be indicated carefully.

[Primary ciliary dyskinesia (Pcd) in Austria]

INTRODUCTION

Primary ciliary dyskinesia (PCD) is a rare hereditary recessive disease with symptoms of recurrent pneumonia, chronic bronchitis, bronchiectasis, and chronic sinusitis. Chronic rhinitis is often the presenting symptom in newborns and infants. Approximately half of the patients show visceral mirror image arrangements (situs inversus). In this study, we aimed 1) to determine the number of paediatric PCD patients in Austria, 2) to show the diagnostic and therapeutic modalities used in the clinical centres and 3) to describe symptoms of children with PCD.

PATIENTS, MATERIAL AND METHODS

For the first two aims, we analysed data from a questionnaire survey of the European Respiratory Society (ERS) task force on Primary Ciliary Dyskinesia in children. All paediatric respiratory units in Austria received a questionnaire. Symptoms of PCD patients from Vienna Children's University Hospital (aim 3) were extracted from case histories.

RESULTS

In 13 Austrian clinics 48 patients with PCD (36 aged from 0-19 years) were identified. The prevalence of reported cases (aged 0-19 yrs) in Austria was 1:48000. Median age at diagnosis was 4.8 years (IQR 0.3-8.2), lower in children with situs inversus compared to those without (3.1 vs. 8.1 yrs, p = 0.067). In 2005-2006, the saccharine test was still the most commonly used screening test for PCD in Austria (45%). Confirmation of the diagnosis was usually by electron microscopy (73%). All clinics treated exacerbations immediately with antibiotics, 73% prescribed airway clearance therapy routinely to all patients. Other therapies and diagnostic tests were applied very inconsistently across Austrian hospitals. All PCD patients from Vienna (n = 13) had increased upper and lower respiratory secretions, most had recurring airway infections (n = 12), bronchiectasis (n = 7) and bronchitis (n = 7).

CONCLUSION

Diagnosis and therapy of PCD in Austria are inhomogeneous. Prospective studies are needed to learn more about the course of the disease and to evaluate benefits and harms of different treatment strategies.

Ultrastructural abnormalities of respiratory cilia: a 25-year experience

CONTEXT

Ciliary dyskinesia is a rare, but significant, cause of chronic respiratory infections, and transmission electron microscopy is a critical adjunct to making the diagnosis.

OBJECTIVE

To investigate a single institution's experience with patients demonstrating abnormal ciliary ultrastructure.

DESIGN

Retrospective clinicopathologic review of 278 bronchial or nasal turbinate brushings or biopsies from 1983 through 2007.

RESULTS

There were 12 women and 9 men (mean age, 19.6 years; range, 1-54 years) with abnormal ciliary ultrastructure. Clinical history was unavailable in 3 patients, 15 (83%) of 18 patients presented with chronic or recurrent upper respiratory infections, and 3 (17%) presented with infertility. Seven (39%) of 18 patients had findings of Kartagener syndrome with situs inversus, dextrocardia, and bronchiectasis. Truncation or absence of inner or outer dynein arms occurred in 15 (71%) of 21 cases, and 5 (24%) revealed transposition defects with displacement of the central microtubules and peripheral doublets in 9 + 0 and 8 + 1 patterns. Radial spoke defects with microtubular disarray occurred in 4 (19%) of 21 cases. Compound cilia with multiple axonemes within a single outer sheath and supernumerary microtubules each occurred in 2 (10%) of the cases. Random ciliary orientation was also found in 2 (10%) of the cases, and dense granular basal body inclusions occurred in 1 case (5%). Multiple abnormalities occurred in 6 (29%) of the 21 cases.

CONCLUSIONS

Most patients presented with chronic respiratory tract infections or infertility. Dynein arm defects, transposition defects, and radial spoke defects were the most commonly encountered abnormal findings. Less-frequent abnormal findings included compound cilia, supernumerary microtubules, and dense granular basal body inclusions.

Mouse dynein axonemal intermediate chain 2: cloning and expression

Ovarian follicular development is a complex process. Investigation of the mechanisms regulating the initiation of follicular growth, and the growth and differentiation of preantral follicles is of great interest. In an effort to clone follicular development-related genes, we selected a partial cDNA fragment by differential display reverse-transcription PCR using total RNA extracted from 5-day-old and 10-day-old mouse ovaries, and its open reading frame was obtained by rapid amplification of cDNA ends. Sequencing showed that the fragment is the mouse dynein axonemal intermediate chain 2 gene (Dnaic2), which has an 87% homology with human DNAI2, a candidate gene for primary ciliary dyskinesia. Northern and western analyses indicate that Dnaic2 produces an approximate 3 kb mRNA that is translated into an approximate 70 kDa protein. The mRNA is predominantly expressed in mouse ovary, testis, and lung. In mouse ovaries, Dnaic2 mRNA was detected at high levels in vivo on day 10, with a subsequent decrease on days 15 and 20, in adult and old ovaries. However, Dnaic2 expression was weak on day 5. Dnaic2 protein was localized on the surface of the oocyte. No obvious fluorescence signal was detected in primordial and primary follicles, while strong signals were detected on the oocyte surface of secondary and antral follicles, in particular for secondary follicles in day 10. These data suggest that Dnaic2 plays a role in ovarian follicular development.

The genetic basis of male reproductive failure

Evolving therapies have allowed the use of sperm from men with spermatogenic compromise, obstructive azoospermia, and sperm functional deficiency, enabling these men to procreate when unable to do so naturally. The genetic basis of only a portion of these conditions is known and research must be pursued into the genetic underpinnings of those that have not yet been delineated. Education and provision of information to patients is the responsibility of all involved in the care of men with reproductive failure. The author concentrates on some of the known causes of nonobstructive azoospermia and obstructive azoospermia with a well-established genetic cause such as congenital bilateral absence of the vas deferens.

Accelerated mortality from hydrocephalus and pneumonia in mice with a combined deficiency of SPAG6 and SPAG16L reveals a functional interrelationship between the two central apparatus proteins

SPAG6 and SPAG16L are proteins localized to the "9+2" axoneme central apparatus. Both are essential for sperm motility and male fertility. These two proteins are also expressed in other tissues containing ciliated cells, such as brain and lung. To study the effects of combined deficiency of these two proteins, a double mutant mouse model was created. The double mutant mice displayed a more profound phenotype of growth retardation and hydrocephalus compared to mice nullizygous for SPAG6 and SPAG16L alone. The double mutant mice died younger, and mortality was significantly higher than in single mutant mice. In addition, the double mutant mice demonstrated pneumonia and its complications, including hemorrhage, edema, and atelectasis, phenotypes not observed in mice nullizygous for mutations in the individual genes. No other cilia-related phenotypic change was detected in double mutant mice including lateralization defects. The ultrastructure of cilia in both the brain and lung of the double mutant mice appeared normal. This model of combined SPAG6 and SPAG16L deficiency provides a new platform to study primary ciliary dyskinesia. The findings also demonstrate that SPAG6 and SPAG16L have related roles in controlling the function of cilia in the brain and lung.

A positive feedback mechanism governs the polarity and motion of motile cilia

Ciliated epithelia produce fluid flow in many organ systems, ranging from the respiratory tract where it clears mucus to the ventricles of the brain where it transports cerebrospinal fluid. Human diseases that disable ciliary flow, such as primary ciliary dyskinesia, can compromise organ function or the ability to resist pathogens, resulting in recurring respiratory infections, otitis, hydrocephaly and infertility. To create a ciliary flow, the cilia within each cell need to be polarized coordinately along the planar axis of the epithelium, but how polarity is established in any ciliated epithelia is not known. Here we analyse the developmental mechanisms that polarize cilia, using the ciliated cells in the developing Xenopus larval skin as a model system. We show that cilia acquire polarity through a sequence of events, beginning with a polar bias set by tissue patterning, followed by a refinement phase. Our results indicate that during refinement, fluid flow is both necessary and sufficient in determining cilia polarity. These findings reveal a novel mechanism in which tissue patterning coupled with fluid flow act in a positive feedback loop to direct the planar polarity of cilia.