Practical guide for the diagnosis and management of primary ciliary dyskinesia.

OBJECTIVE: Primary ciliary dyskinesia (PCD) is a relatively rare genetic disorder that affects approximately 1 in 20,000 people. Approximately 50 genes are currently known to cause PCD. In light of differences in causative genes and the medical system in Japan compared with other countries, a practical guide was needed for the diagnosis and management of Japanese PCD patients. METHODS: An ad hoc academic committee was organized under the Japanese Rhinologic Society to produce a practical guide, with participation by committee members from several academic societies in Japan. The practical guide including diagnostic criteria for PCD was approved by the Japanese Rhinologic Society, Japanese Society of Otolaryngology-Head and Neck Surgery, Japanese Respiratory Society, and Japanese Society of Pediatric Pulmonology. RESULTS: The diagnostic criteria for PCD consist of six clinical features, six laboratory findings, differential diagnosis, and genetic testing. The diagnosis of PCD is categorized as definite, probable, or possible PCD based on a combination of the four items above. Diagnosis of definite PCD requires exclusion of cystic fibrosis and primary immunodeficiency, at least one of the six clinical features, and a positive result for at least one of the following: (1) Class 1 defect on electron microscopy of cilia, (2) pathogenic or likely pathogenic variants in a PCD-related gene, or (3) impairment of ciliary motility that can be repaired by correcting the causative gene variants in iPS cells established from the patient's peripheral blood cells. CONCLUSION: This practical guide provides clinicians with useful information for the diagnosis and management of PCD in Japan.

Circulating extracellular vesicles are associated with pathophysiological condition including metabolic syndrome-related dysmetabolism in children and adolescents with obesity.

Obesity of children and adolescents (OCA) is often accompanied by metabolic syndrome (MetS), which often leads to adult obesity and subsequent complications, yet the entire pathophysiological response is not fully understood. The number and composition of circulating extracellular vesicles (EV) reflect overall patient condition; therefore, we investigated the pathophysiological condition of OCA, including MetS-associated dysmetabolism, using circulating EVs. In total, 107 children and adolescents with or without obesity (boys, n = 69; girls, n = 38; median age, 10 years) were enrolled. Circulating EV number and EV protein composition were assessed via flow cytometry and liquid chromatography tandem-mass spectrometry, respectively. In a multivariate analysis, relative body weight (standardized partial regression coefficient (SPRC) 0.469, P = 0.012) and serum triglyceride level (SPRC 0.548, P < 0.001) were detected as independent parameters correlating with circulating EV number. Proteomic analysis identified 31 upregulated and 45 downregulated EV proteins in OCA. Gene ontology analysis revealed upregulated proteins to be involved in various biological processes, including intracellular protein transport, protein folding, stress response, leukocyte activation, innate immune response, and platelet degranulation, which can modulate lipid and glucose metabolism, skeletal and cardiac muscle development, inflammation, immune response, carcinogenesis, and cancer progression. Notably, several identified EV proteins are involved in neuro-development, neurotransmitter release, and neuro-protective agents in OCA. Circulating EVs were derived from adipocytes, hepatocytes, B cell lymphocytes, and neurons. Circulating EV number is significantly associated with MetS-related dysmetabolism and the EV protein cargo carries a special "signature" that reflects the alteration of various biological processes under the pathophysiological condition of OCA. KEY MESSAGES: Circulating EV number correlates with physical and laboratory parameters for obesity in children and adolescents. Relative body weight and triglyceride are independent factors for increased circulating EVs. EV composition is significantly changed in obesity of children and adolescents. Identified EV composition changes associated with obesity and involves in metabolism, immune response, and cancer progression. Circulating EVs are partially derived from adipocyte, hepatocytes, B cells, and neurons.

A Novel Homozygous Variant in GAS2L2 in Two Sisters with Primary Ciliary Dyskinesia.

Primary ciliary dyskinesia (PCD) is a rare hereditary disease. We herein report two sisters in their 20s with suspected PCD. They were both born at full term and did not have situs inversus. Chest computed tomography showed similar signs of bronchiectasis in both siblings. Genetic examinations of the family confirmed that the sisters both harbored a homozygous variant in the growth-arrest-specific 2-like 2 (GAS2L2) gene. This is the third report of a family with PCD caused by a GAS2L2 variant.

Squamous cell carcinoma antigens are sensitive biomarkers for atopic dermatitis in children and adolescents: a cross-sectional study.

BACKGROUND: We recently reported that squamous cell carcinoma antigen 2 (SCCA2) is a reliable biomarker for atopic dermatitis (AD). OBJECTIVE: To further clarify its utility, we investigated for effects of comorbid allergies and AD treatment on serum SCCA levels. METHODS: Volunteers <18 years old were recruited through our website. Their allergic status was elucidated using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. We also recruited pediatric patients who were hospitalized because of severe AD. The serum levels of SCCA1 and SCCA2 were measured by enzyme-linked immunosorbent assays. In the severe AD patients, the levels of thymus and activation-regulated chemokine (TARC), SCCA1, and SCCA2 were measured before and after hospitalization. The severity of AD was assessed using the severity scoring of atopic dermatitis (SCORAD). RESULTS: A total of 576 participants (547 volunteers and 29 patients) were enrolled in the study. The levels of SCCA1 and SCCA2 were significantly higher in volunteers with mild AD and patients with severe AD than in healthy volunteers without allergic diseases. The levels were not elevated in those who had mild bronchial asthma or allergic rhinitis without AD. TARC, SCCA1, and SCCA2 were decreased during the treatment in severe AD patients, reflecting clinical improvement in response to treatment. Linear regression analysis for predicting a decrease in the SCORAD index showed R2 values of 0.16, 0.38, and 0.48 for TARC, SCCA1, and SCCA2, respectively. CONCLUSION: SCCAs, especially SCCA2, are sensitive biomarkers for detecting AD in children and adolescents and for assessing the severity and response to treatment of severe AD.

Drug hypersensitivity reactions in Asia: regional issues and challenges.

There are geographical, regional, and ethnic differences in the phenotypes and endotypes of patients with drug hypersensitivity reactions (DHRs) in different parts of the world. In Asia, aspects of drug hypersensitivity of regional importance include IgE-mediated allergies and T-cell-mediated reactions, including severe cutaneous adverse reactions (SCARs), to beta-lactam antibiotics, antituberculous drugs, nonsteroidal anti-inflammatory drugs (NSAIDs) and radiocontrast agents. Delabeling of low-risk penicillin allergy using direct oral provocation tests without skin tests have been found to be useful where the drug plausibility of the index reaction is low. Genetic risk associations of relevance to Asia include human leucocyte antigen (HLA)-B*1502 with carbamazepine SCAR, and HLA-B*5801 with allopurinol SCAR in some Asian ethnic groups. There remains a lack of safe and accurate diagnostic tests for antituberculous drug allergy, other than relatively high-risk desensitization regimes to first-line antituberculous therapy. NSAID hypersensitivity is common among both adults and children in Asia, with regional differences in phenotype especially among adults. Low dose aspirin desensitization is an important therapeutic modality in individuals with cross-reactive NSAID hypersensitivity and coronary artery disease following percutaneous coronary intervention. Skin testing allows patients with radiocontrast media hypersensitivity to confirm the suspected agent and test for alternatives, especially when contrasted scans are needed for future monitoring of disease relapse or progression, especially cancers.

Species differences in circulation and inflammatory responses in children with common respiratory adenovirus infections.

Human adenoviruses (HAdVs) cause severe inflammatory respiratory infections, but previous epidemiological studies lacked analysis of the characteristics of the inflammation. Consecutive patients <13 years old with acute febrile illness during a 2-year period were tested. HAdV strains were isolated from nasopharyngeal swabs, and molecular identification was performed by hexon, fiber, and species-specific PCR methods. Blood inflammatory markers, including the white blood cell (WBC) count, CRP, and 29 cytokines, were measured. A total of 187 patients were enrolled, and HAdV types were identified from 175 patients (93.5%). Species C (types 2, 1, 5, and 6, in order of frequency) was most common at 37.1%, followed by B (type 3) at 30.9% and E (type 4) at 26.9%. Species C was detected predominantly in 1-year-old, whereas B and E were in older ages. Species C and B had seasonal circulation patterns, but E was found in only one season during the 2-year study period. The WBC count was highest in patients with species C. Eleven of the 29 tested serum cytokines were detected. Seven kinds, including G-CSF, IL-6, and TNF-α, were elevated in species C infections, whereas IL-10 was lowest in species C. Species differences in inflammatory responses, especially regarding serum cytokines were described in common pediatric HAdV infections. Species C causes the strongest inflammatory responses in young children.

Histamine-releasing factor enhances food allergy.

Food allergy occurs due to IgE- and mast cell-dependent intestinal inflammation. Previously, we showed that histamine-releasing factor (HRF), a multifunctional protein secreted during allergy, interacts with a subset of IgE molecules and that the HRF dimer activates mast cells in an HRF-reactive IgE-dependent manner. In this study, we investigated whether HRF plays any role in food allergy. Specifically, we determined that prophylactic and therapeutic administration of HRF inhibitors that block HRF-IgE interactions reduces the incidence of diarrhea and mastocytosis in a murine model of food allergy. Food allergy-associated intestinal inflammation was accompanied by increased secretion of the HRF dimer into the intestine in response to proinflammatory, Th2, and epithelial-derived cytokines and HRF-reactive IgE levels at the elicitation phase. Consistent with these data, patients with egg allergy had higher blood levels of HRF-reactive IgE compared with individuals that were not hypersensitive. Successful oral immunotherapy in egg-allergy patients and food-allergic mice reduced HRF-reactive IgE levels, thereby suggesting a pathological role for HRF in food allergy. Together, these results suggest that antigen and HRF dimer amplify intestinal inflammation by synergistically activating mast cells and indicate that HRF has potential as a therapeutic target in food allergy.

ß2 adrenergic agonist suppresses eosinophil-induced epithelial-to-mesenchymal transition of bronchial epithelial cells.

BACKGROUND: Epithelial-mesenchymal transition is currently recognized as an important mechanism for the increased number of myofibroblasts in cancer and fibrotic diseases. We have already reported that epithelial-mesenchymal transition is involved in airway remodeling induced by eosinophils. Procaterol is a selective and full ß2 adrenergic agonist that is used as a rescue of asthmatic attack inhaler form and orally as a controller. In this study, we evaluated whether procaterol can suppress epithelial-mesenchymal transition of airway epithelial cells induced by eosinophils. METHODS: Epithelial-mesenchymal transition was assessed using a co-culture system of human bronchial epithelial cells and primary human eosinophils or an eosinophilic leukemia cell line. RESULTS: Procaterol significantly inhibited co-culture associated morphological changes of bronchial epithelial cells, decreased the expression of vimentin, and increased the expression of E-cadherin compared to control. Butoxamine, a specific ß2-adrenergic antagonist, significantly blocked changes induced by procaterol. In addition, procaterol inhibited the expression of adhesion molecules induced during the interaction between eosinophils and bronchial epithelial cells, suggesting the involvement of adhesion molecules in the process of epithelial-mesenchymal transition. Forskolin, a cyclic adenosine monophosphate-promoting agent, exhibits similar inhibitory activity of procaterol. CONCLUSIONS: Overall, these observations support the beneficial effect of procaterol on airway remodeling frequently associated with chronic obstructive pulmonary diseases.

Whole-exome sequencing identification of novel DNAH5 mutations in a young patient with primary ciliary dyskinesia.

Primary ciliary dyskinesia (PCD) is a rare genetic disorder caused by structural and/or functional impairment of cilia throughout the whole body. Early diagnosis of PCD is important for the prevention of long­term sequelae, however early diagnosis is a challenge due to the phenotypic heterogeneity of PCD. In the current study, the patient with PCD was diagnosed at nine years old following several efforts to control intractable airway symptoms. The patient experienced a chronic productive cough beginning in early childhood and had multiple episodes of pneumonia and otitis media with effusion and sinusitis. No situs inversus or other heterotaxias were reported. Serial chest X­rays exhibited persistent atelectasis and bronchiectasis in the right middle lobe. When the patient was nine years old, electron microscopy of his cilia and genetic analysis were conducted. Electron microscopy of a biopsy specimen from the nasal mucosa indicated loss of the outer dynein arms. Whole­exome analysis of the genome demonstrated the presence of compound heterozygous mutations in DNAH5: NM_001369.2:c.5983C>T, p.Arg1995X in exon 36 and NM_001369.2:c.9101delG, p.Gly3034ValfsX22 in exon 54; neither of which have been previously reported in the literature in a Japanese patient. Notably, this case is, to the best of our knowledge, the first reported case of PCD caused by the DNAH5 mutation in a Japanese patient.

Recent advances in primary ciliary dyskinesia.

Primary ciliary dyskinesia (PCD) is a genetic disease inherited in an autosomal recessive manner. The prevalence of PCD is estimated to be 1 in 20,000 live births. Congenital abnormality of the primary cilia results in situs inversus in 50% of patients. Decreased function of motile cilia causes chronic rhinosinusitis, otitis media with effusion, bronchiectasis and infertility. Cases with situs inversus are considered to show "Kartagener's syndrome", and diagnosis is not difficult. However, in cases without situs inversus, the diagnosis is much more troublesome. PCD without situs inversus is thus probably underdiagnosed. Prolonged chronic cough represents an important symptom that is seen in most patients. The diagnosis of PCD requires the presence of the characteristic clinical phenotypes and either: (1) specific ciliary ultrastructural defects identified by transmission electron microscopy in biopsy samples of respiratory epithelium; or (2) identification of mutation in one of the genes known to be associated with PCD. Nasal nitric oxide concentration is extremely low in PCD, and this could be useful for screening of the disease. At present, no fundamental therapies are available for PCD. Diagnosis in the early stages is important to prevent progression of bronchiectasis and deterioration of lung function by guidance for daily life, immunization, cessation of smoking and prompt therapy at the time of respiratory tract infection. Since PCD is inherited in an autosomal-recessive manner, genetic counseling is necessary after definite diagnosis.

Montelukast suppresses epithelial to mesenchymal transition of bronchial epithelial cells induced by eosinophils.

Epithelial to mesenchymal transition (EMT) is a mechanism by which eosinophils can induce airway remodeling. Montelukast, an antagonist of the cysteinyl leukotriene receptor, can suppress airway remodeling in asthma. The purpose of this study was to evaluate whether montelukast can ameliorate airway remodeling by blocking EMT induced by eosinophils. EMT induced was assessed using a co-culture system of human bronchial epithelial cells and human eosinophils or the eosinophilic leukemia cell lines, Eol-1. Montelukast inhibited co-culture associated morphological changes of BEAS-2b cells, decreased the expression of vimentin and collagen I, and increased the expression of E-cadherin. Montelukast mitigated the rise of TGF-ß1 production and Smad3 phosphorylation. Co-culture of human eosinophils with BEAS-2B cells significantly enhanced the production of CysLTs compared with BEAS-2B cells or eosinophils alone. The increase of CysLTs was abolished by montelukast pre-treatment. Montelukast had similar effects when co-culture system of Eol-1 and BEAS-2B was used. This study showed that montelukast suppresses eosinophils-induced EMT of airway epithelial cells. This finding may explain the mechanism of montelukast-mediated amelioration of airway remodeling in bronchial asthma.

Eosinophils promote epithelial to mesenchymal transition of bronchial epithelial cells.

Eosinophilic inflammation and remodeling of the airways including subepithelial fibrosis and myofibroblast hyperplasia are characteristic pathological findings of bronchial asthma. Epithelial to mesenchymal transition (EMT) plays a critical role in airway remodelling. In this study, we hypothesized that infiltrating eosinophils promote airway remodelling in bronchial asthma. To demonstrate this hypothesis we evaluated the effect of eosinophils on EMT by in vitro and in vivo studies. EMT was assessed in mice that received intra-tracheal instillation of mouse bone marrow derived eosinophils and in human bronchial epithelial cells co-cultured with eosinophils freshly purified from healthy individuals or with eosinophilic leukemia cell lines. Intra-tracheal instillation of eosinophils was associated with enhanced bronchial inflammation and fibrosis and increased lung concentration of growth factors. Mice instilled with eosinophils pre-treated with transforming growth factor(TGF)-ß1 siRNA had decreased bronchial wall fibrosis compared to controls. EMT was induced in bronchial epithelial cells co-cultured with human eosinophils and it was associated with increased expression of TGF-ß1 and Smad3 phosphorylation in the bronchial epithelial cells. Treatment with anti-TGF-ß1 antibody blocked EMT in bronchial epithelial cells. Eosinophils induced EMT in bronchial epithelial cells, suggesting their contribution to the pathogenesis of airway remodelling.

Higher allergenicity of high molecular weight hydrolysed wheat protein in cosmetics for percutaneous sensitization.

BACKGROUND: Wheat protein derivatives are used in a variety of products worldwide. Gluten is commercially used 'as is' or with modifications such as hydrolysis, which is carried out to overcome its insolubility. Several cases of contact urticaria following exposure to hydrolysed wheat protein (HWP) in cosmetics or of anaphylaxis caused by deamidated gluten in food or non-food products have been described. OBJECTIVES: To evaluate the types of HWP that have higher allergenicity for percutaneous sensitization. METHODS: We enrolled 7 patients with wheat-dependent exercise-induced anaphylaxis who had been sensitized to HWP primarily through the percutaneous and/or the rhinoconjunctival route by using facial soap containing HWP. Reaction to wheat proteins was confirmed by IgE immunoblotting and basophil CD203c expression with six HWP variants. RESULTS: The IgE of all the patients reacted to HWPs composed of large polypeptide aggregates. High molecular weight (MW) HWPs were also found to induce significant enhancement of basophil CD203c expression. CONCLUSIONS: HWPs composed of large polypeptide aggregates possibly induce sensitization to a greater degree than lower-MW HWPs. Basophil surface CD203c expression is useful for evaluating the allergenicity of HWPs.

Elevated numbers of cells producing interleukin-5 and interleukin-10 in a boy with Kimura disease.

Kimura disease is a rare disorder of unknown etiology, characterized by the presence of benign subcutaneous granuloma, marked peripheral blood eosinophilia and elevation of the immunglobulin E (IgE) serum level. Here, we present a case of a 12-year-old boy with Kimura disease who had a history of repeated severe influenza virus A infection. Along with the characteristic histological findings of granuloma, including eosinophil infiltration, enzyme-linked immunospot assay showed elevated numbers of IL-5- and IL-10-producing cells in the peripheral blood. Immunohistochemical evaluation, however, did not detect IL-5 in the tissue. Possible cytokine dysregulation in Kimura disease was suggested, but the pathogenesis remains unclear.

An 8-year-old boy with hypereosinophilic syndrome.

Hypereosinophilic syndrome (HES) is a heterogeneous group of uncommon disorders characterized by the presence of marked peripheral blood eosinophilia and tissue eosinophilia, resulting in a wide variety of clinical manifestations. We present the case of an 8-year-old boy with HES. He complained of recurrent abdominal pain, general fatigue, and diarrhea. Laboratory data showed marked eosinophilia, elevated total IgE with positive specific IgE antibodies to common inhalant and food allergens, and elevated serum CCL17/TARC. A chest CT scan revealed central bronchiectasis, bronchial wall thickening, a mosaic attenuation pattern, and multiple small nodules in lung parenchyma; abdominal CT showed a thickened bladder wall. Gastrointestinal endoscopy revealed scarring in the gastric mucosa and mucosal erosion in the duodenum. Immunohistochemical examination demonstrated numerous eosinophil infiltrations with extensive extracellular eosinophil major basic protein deposition in the gastric mucosa. Only high-dose oral steroid was effective and cyclosporine appeared to have a steroid-sparing effect. HES is extraordinary rare in children and the long-term prognosis in pediatric HES is not well known. Comprehensive diagnostic procedures are vital for the early detection and management of complications in pediatric HES.

Differential activation of eosinophils by 'probiotic' Bifidobacterium bifidum and 'pathogenic' Clostridium difficile.

BACKGROUND: Recent studies suggest that probiotics alleviate pathophysiological processes of allergic diseases and inflammatory bowel diseases, whereas 'non-probiotic' microflora has negative effects. However, the underlying mechanisms are not well known, especially in relation to eosinophils, the major effector cells of these inflammatory diseases. OBJECTIVE: To investigate the effects of probiotic Bifidobacterium bifidum (BB) on human eosinophil functions compared with pathogenic Clostridium difficile (CD). METHODS: Peripheral human eosinophils were cultured with heat-killed BB or CD. FISH-labeled CD and BB were incubated with eosinophils visualized by confocal laser scanning microscopy. Superoxide generation and degranulation of eosinophils were measured with the cytochrome c reduction method and the eosinophil-derived neurotoxin (EDN) release assay, respectively. RESULTS: Confocal microscopy revealed that Cy3-labeled CD and BB were apparently ingested by eosinophils. Both bacteria induced minimal superoxide generation. However, CD elicited significantly higher EDN release than BB. GM-CSF significantly enhanced EDN release by CD but not by BB. Bacterial-induced EDN release was calcium dependent. CONCLUSION: The beneficial effect of probiotic BB might be explained, at least in part, by its ability to decrease EDN release from eosinophils compared with 'pathogenic' CD.

[Factors related to recurrent wheezing after hospitalization with RSV infection with the children who were aged three years old or younger: a questionnaire survey].

Respiratory syncytial virus (RSV) infections in infancy have been related to the subsequent recurrent wheezing and asthma. However, there are a few reports about the relationship between RSV infection and subsequent wheezing in Japan. We sought to determine the contributing factors for wheezing illness after RSV infection in 99 Japanese patients with RSV-associated hospitalizations by questionnaire and follow up survey. Fifty eight patients, who were aged three years old or younger on admission and could be followed up more than one year, were analyzed. The mean duration from discharge to last survey were 703.6+/-105.5 days (432-950 days), the mean age on admission were 9.4+/-8.8 months (0-30 months). Wheezing episodes after discharge were reported in 29 of the subjects (50.0%). Univariable and multivariable analysis identified that the subsequent wheezing after RSV infection were related with the history of wheezing before admission and attending a daycare. The patient's age on admission, the patient's atopic profile, history of continuous nocturnal cough before admission, gestational ages, birth weight, length of hospital stay, perinatal abnormality, environmental tobacco smoke, parental history of allergy and asthma, presence of sibling and sibling history of allergy and asthma were not associated with subsequent wheezing. These results suggest that some host factors susceptible to wheezing and chance of infection due to attending a daycare may be related to recurrent wheezing possibly onset of bronchial asthma, after RSV infection.