Combined airways: impact of upper airway on lower airway

Evaluation of sinonasal involvement in patients with asthma and chronic obstructive pulmonary disease

Background: Asthma and chronic obstructive pulmonary disease (COPD) are the most common obstructive diseases. Based on the similarities, we aimed to evaluate sinonasal symptoms in patients with asthma or COPD, and compare the two diseases with regard to upper-airway involvement. Methods: Patients with asthma or with COPD who were followed up at Ankara University Immunology and Allergy or Chest Diseases Departments were included in the study. The participants went through pulmonary function tests, skin-prick tests, and disease severity assessment of either disease. Nasal endoscopic evaluations of all the patients were performed in the Department of Otorhinolaryngology. Lund-Mackay scoring was performed on the computed tomography of the paranasal sinus. Chronic rinosinusitis (CRS) diagnosis was made as recent guidelines. Results: A total of 112 subjects (number of women/men: n = 67/45; median age, 49 years [The range for IQR was 22 years]) were included in the study. Fifty-five patients had asthma, 33 had COPD, and 24 were healthy controls. Nasal symptoms were more frequent in the patients with asthma (patients with asthma, n = 52 [98%]; patients with COPD, n = 17 [52%]; controls, n = 9 [38%]) (p < 0.001). The median (IQR) 22-item Sino-Nasal Outcome Test (SNOT-22) questionnaire score was higher in the patients with asthma (33 [20-50]) than in the patients with COPD (8 [1.5-18.7]) and the control group (3.5 [0-18.7]) (p < 0.01). Patients with asthma had significantly higher prevalence rates of rhinosinusitis than did those in the COPD and the control groups (36%, 15.6%, 8.3%, respectively; p < 0.01). The SNOT-22 optimal cutoff score was calculated as ≥11 to detect the score limit for CRS prediction with the best sensitivity and specificity. Conclusion: As a result, patients with both asthma and COPD may have upper-airway symptoms. CRS, was primarily seen in the patients with asthma. Accordingly, SNOT-22 scores were higher in the patients with asthma than in those in the COPD and the control groups. A referral to the Ear Nose Throat department for further evaluation with nasal endoscopy and computed tomography of the paranasal may be required in a subgroup of patients.

Risk factors of sleep-disordered breathing and poor asthma control in children with asthma

BACKGROUND

Sleep-disordered breathing (SDB) may lead to poor asthma control in children.

OBJECTIVE

To identify risk factors of SDB in children with asthma and assess its impact on asthma control.

METHODS

In this cross-sectional study, we collected data of outpatients with asthma at the Children's Hospital of Chongqing Medical University from June 2020 to August 2021. The Pediatric Sleep Questionnaire-Sleep-Related Breathing Disorder and the age-appropriate asthma control tests Childhood Asthma Control Test and Test for Respiratory and Asthma Control in Kids were completed.

RESULTS

We enrolled 397 children with a male-to-female ratio of 1.7:1 and a mean age of 5.70 ± 2.53 years. The prevalence of SDB was 21.6%. Allergic rhinitis (odds ratio OR = 3.316), chronic tonsillitis (OR = 2.246), gastroesophageal reflux (OR = 7.518), adenoid hypertrophy (OR = 3.479), recurrent respiratory infections (OR = 2.195), and a family history of snoring (OR = 2.048) were risk factors for the development of combined SDB in children with asthma (p < 0.05). Asthma was poorly controlled in 19.6% of the children. SDB (OR = 2.391) and irregular medication use (OR = 2.571) were risk factors for poor asthma control (p < 0.05).

CONCLUSIONS

Allergic rhinitis, chronic tonsillitis, gastroesophageal reflux, adenoid hypertrophy, recurrent respiratory infections, and a family history of snoring were independent risk factors for the development of SDB in children with asthma. SDB and irregular medication use were independent risk factors for poor asthma control.

Adenotonsillectomy, bronchoscopy and bronchoalveolar lavage in the management of preschool children with severe asthma: pilot study

PURPOSE

This is a pilot study that describes the feasibility and clinical course of a cohort of preschool children with severe asthma undergoing a combined adenotonillectomy (TA), bronchoscopy (B), and bronchoalveolar lavage (BAL) procedure.

METHODS

A retrospective cohort study of preschool patients with severe asthma who underwent a combined TA-B-BAL procedure between 2012 and 2019. Subjects were treated at a tertiary care asthma clinic and had a diagnosis of preschool asthma according to the Canadian Thoracic Society Guidelines. Data on demographics, clinical characteristics, medication use, virology and microbiology from bronchoalveolar lavage, and asthma control questionnaires were collected. Variables were analyzed using paired t test.

RESULTS

Eighteen preschool subjects (mean age 3.19 ± 1.13 years) with severe asthma were identified through the asthma clinic. Patients treated with standard asthma care and a combined  TA-B-BAL procedure  experienced a decrease in the number of oral steroid courses (p = 0.017), emergency department visits (p = 0.03) and wheezing exacerbations (p = 0.026) following the procedure. Ten patients experienced clinically meaningful improvements in TRACK scores after the procedure (p < 0.001).

CONCLUSION

This pilot study provides early evidence that a combined TA-B-BAL procedure is feasible in preschool children with severe asthma and that the procedure may reduce asthma medication use and hospital visits.

Manifesto on united airways diseases (UAD): an Interasma (global asthma association - GAA) document

OBJECTIVE

The large amount of evidence and the renewed interest in upper and lower airways involvement in infectious and inflammatory diseases has led Interasma (Global Asthma Association) to take a position on United Airways Diseases (UAD).

METHODS

Starting from an extensive literature review, Interasma executive committee discussed and approved this Manifesto developed by Interasma scientific network (INES) members.

RESULTS

The manifesto describes the evidence gathered to date and defines, states, advocates, and proposes issues on UAD (rhinitis, rhinosinusitis and nasal polyposis), and concomitant/comorbid lower airways disorders (asthma, chronic obstructive pulmonary disease, bronchiectasis, cystic fibrosis, obstructive sleep apnoea) with the aim of challenging assumptions, fostering commitment, and bringing about change. UAD refers to clinical pictures characterized by the coexistence of upper and lower airways involvement, driven by a common pathophysiological mechanism, leading to a greater burden on patient's health status and requiring an integrated diagnostic and therapeutic plan. The high prevalence of UAD must be taken into account. Upper and lower airways diseases influence disease control and patient's quality of life.

CONCLUSIONS

Patients with UAD need to have a timely and adequate diagnosis, treatment, and, when recommended, referral for management in a specialized center. Diagnostic testing including skin prick or serum specific IgE, lung function, fractional exhaled nitric oxide (FeNO), polysomnography, allergen-specific immunotherapies, biological therapies and home based continuous positive airway pressure (CPAP) whenever these are recommended, should be part of the management plan for UAD. Education of medical students, physicians, health professionals, patients and caregivers on the UAD is needed.

Effect of Dermatophagoides pteronyssinus Immunotherapy on Upper and Lower Airway Eosinophilic Inflammatory Response to Nasal Allergen Challenge

Purpose

It remains unknown whether allergen-specific immunotherapy (AIT) could attenuate airway inflammatory response triggered by allergen exposure.

Methods

We performed Dermatophagoides pteronyssinus (Der-p) nasal provocation tests (NPTs) in allergic rhinitis (AR) and/or asthma patients without AIT (non-AIT), or at 16, 52, 104, or 156 weeks after Der-p AIT. Rhinitis and asthma visual analog scale (VAS; VAS of nasal symptoms [VAS-NS], VAS of asthma symptoms), the rhinoconjunctivitis quality of life questionnaire (RQLQ), nasal lavage, sputum induction, fractional exhaled nitric oxide (FeNO), nasal airway resistance, pulmonary function, and airway hyperresponsiveness were performed before and after NPT.

Results

Non-AIT subjects demonstrated significantly higher VAS-NS before and after NPT compared to AIT subjects (P < 0.05). NPT response was positive in 14 (100%) non-AIT, 7 (70%) 16 weeks-AIT, 6 (60%) 52 weeks-AIT, 6 (60%) 104 weeks-AIT, and 2 (20%) 156 weeks-AIT subjects. The NPT grade significantly correlated with AIT duration and baseline RQLQ score (r = −0.561, P < 0.001 and r = 0.525, P < 0.001, respectively). Sputum and nasal lavage eosinophil count, and FeNO in non-AIT subjects were significantly increased 6 hours after NPT (P < 0.05). AIT subjects did not change their sputum or nasal lavage eosinophil count before and after NPT. Subjects with 156 weeks-AIT demonstrated significantly lower levels of sputum and nasal lavage eosinophil count before and after NPT when compared with non-AIT patients (P < 0.05). Sputum eosinophil counts positively correlated with nasal lavage eosinophil counts at baseline and 6 hours after NPT (r = 0.719, P = 0.006 and r = 0.823, P < 0.001, respectively) in non-AIT patients.

Conclusion

Our results show that AIT can attenuate both upper and lower airway immune response to nasal allergen exposure in patients with AR and/or asthma.

Identification of surrogate prognostic biomarkers for allergic asthma in nasal epithelial brushing samples by WGCNA

BACKGROUND

Allergic asthma is a lower respiratory tract disease of Th2 inflammation with multiple molecular mechanisms. The upper and lower airways can be unified by the concept of a united airway and, as such, gene expression studies of upper epithelial cells may provide effective surrogate biomarkers for the prognostic study of allergic asthma.

OBJECTIVE

To identify surrogate biomarkers in upper airway epithelial cells for the prognostic study of allergic asthma.

METHODS

Nasal epithelial cell gene expression in 40 asthmatic and 17 healthy control subjects were analyzed by weighted gene coexpression network analysis (WGCNA) to identify gene network modules and profiles in allergic asthma. Functional enrichment analysis was performed on the coexpression genes in certain highlighted modules.

RESULTS

A total of 13 coexpression modules were constructed by WGCNA from 2804 genes in nasal epithelial brushing samples of the 40 asthmatic and 17 healthy subjects. The number of genes in these modules ranged from 1086 (Turquoise module) to 45 (Salmon). Eight coexpression modules were found to be significantly correlated (P < 0.05) with two clinic traits, namely disease status, and severity. Four modules were positively correlated ( P < 0.05) with the traits and these, therefore, contained genes that are mostly overexpressed in asthma. Contrastingly, the four other modules were found to be negatively correlated with the clinic traits. Functional enrichment analysis of the positively correlated modules showed that one (Magenta) was mainly enriched in mast cell activation and degranulation; another (Pink) was largely involved in immune cell response; the third (Yellow) was predominantly enriched in transmembrane signal pathways; and the last (Blue) was mainly enriched in substructure components of the cells. The hub genes in the modules were KIT, KITLG, GATA2, CD44, PTPRC, and CFTR, and these were confirmed as having significantly higher expression in the nasal epithelial cells. Combining the six hub genes enabled a relatively high capacity for discrimination between asthmatics and healthy subjects with an area under the receiver operating characteristic (ROC) curve of 0.924.

CONCLUSIONS

Our findings provide a framework of coexpression gene modules from nasal epithelial brushing samples that could be used for the prognostic study of allergic asthma.

Poor sleep quality has an adverse effect on childhood asthma control and lung function measures

BACKGROUND

It is unclear as to whether sleep respiratory breathing disorder (SRBD) is a risk factor for uncontrolled asthma in children. The aim of this study was therefore to investigate whether SRBD may have an adverse effect on childhood asthma control and lung function measures.

METHODS

This was a cross-sectional study of 220 children with well-controlled (n = 108), partly controlled (n = 92), and uncontrolled asthma (n = 20) according to the Global Initiative for Asthma guideline. SRBD was assessed using the Pediatric Sleep Questionnaire (PSQ). The association of SRBD with partly controlled/uncontrolled asthma was investigated on multivariate logistic regression analysis.

RESULTS

Of 220 children with asthma, 43 (19.6%) had SRBD: well-controlled, 16.7% (18/108); partly controlled, 21.7% (20/92); and uncontrolled, 25.0% (5/20; P = 0.54). There was a significant difference in forced expiratory volume in 1 s/forced vital capacity (FEV₁ /FVC; P = 0.007) and childhood asthma control test (C-ACT) score (P < 0.001) according to asthma control status, but not in PSQ score (P = 0.18). Children with obstructive sleep apnea (PSQ >0.33) had a lower C-ACT score compared with controls (PSQ ≤0.33; 19.6 ± 5.1 vs 22.0 ± 4.2, P = 0.002). PSQ score was negatively correlated with FEV₁ /FVC (r = -0.16, P = 0.02). On multivariate logistic regression analysis, high PSQ score increased the odds of having partly controlled/uncontrolled asthma by 9.12 (95% CI: 1.04-79.72, P = 0.046) after adjusting for confounding factors.

CONCLUSION

SRBD is an independent risk factor for partly controlled/uncontrolled asthma and has an adverse effect on lung function measures in children. Further research is warranted to determine whether the improvement of sleep quality may also enhance level of asthma control and lung function in children.

Subclinical lower airways correlates of chronic allergic and non-allergic rhinitis

The upper and lower airways behave as a physiological and pathophysiological unit. Subclinical lower airways abnormalities have been described in patients with rhinitis without asthma. These are expressed as bronchial hyperreactivity, abnormalities in lung function and bronchial inflammation, likely as a result of the same phenomenon with systemic inflammatory impact that reaches both the nose and the lungs, which for unknown reasons does not always have a full clinical expression. Patients with rhinitis are at increased risk of developing asthma; therefore, most authors suggest a careful clinical evaluation and monitoring of these patients, especially if symptoms related to inflammation in the lower airways are observed. Although current treatments, such as H1-antihistamines, intranasal steroids and allergen immunotherapy, are quite effective for the management of rhinitis, it is difficult to prove their capacity to prevent asthma among subjects with rhinitis. Evidence showing that the treatment of rhinitis has a favourable impact on indicators of bronchial hyperreactivity and inflammation among subjects that have no symptoms of asthma is more frequently described. In this review, we address the frequency and characteristics of lower airway abnormalities in subjects with rhinitis, both in paediatric and adult populations, their likely predictive value for the development of asthma and the possibilities for therapeutic intervention that could modify the risk of subjects with rhinitis towards presenting asthma.

An intratracheal challenge murine model of asthma: can bronchial inflammation affect the nose?

PURPOSE

Extensive data support the influence of the upper airway on lower airway inflammation and pathophysiology in allergic disease. However, few studies have focused on allergic inflammation in the nose after an isolated lower airway allergen challenge, a situation that can exist clinically when human subjects breathe primarily through the mouth, as occurs when nasally congested. This study used a mouse model to investigate whether upper airway inflammation and hyperresponsiveness were induced by an isolated lower airway allergen challenge.

METHODS

BALB/c mice were sensitized by systemic intraperitoneal injection of ovalbumin/saline and challenged with intratracheal ovalbumin/saline. Inflammation in the nose and lungs was assessed by cytology and histology of nasal tissues and bronchoalveolar lavage fluid (BALF), while nasal airway resistance and response were measured over 3 days post-challenge.

RESULTS

Intratracheal application of an allergen in anaesthetized mice resulted in exclusive deposition in the lower airway. Compared to control animals, ovalbumin-sensitized mice after challenge showed bronchial hyperreactivity and increased IL-5 in the serum BALF, as well as eosinophil infiltration in the lungs. However, nasal histology of the ovalbumin-sensitized mice showed no increase in eosinophil infiltration. The nasal lavage fluid revealed no increase in eosinophils or IL-5, and the nasal airway resistance did not increase after challenge either.

CONCLUSIONS

In a mouse allergy model, exclusive allergen challenge of the lower airway can elicit a pulmonary and systemic allergic response, but does not induce upper airway inflammatory or physiological responses.

Outcomes and cost benefits of functional endoscopic sinus surgery in severely asthmatic patients with chronic rhinosinusitis

OBJECTIVES

To evaluate the outcomes (using validated outcome tools) and cost benefits of functional endoscopic sinus surgery in a population of severely asthmatic patients with chronic rhinosinusitis.

METHODS

A prospective cohort study was conducted. The study comprised consecutive patients diagnosed with asthma and chronic rhinosinusitis for whom medical treatment had failed and who were scheduled for functional endoscopic sinus surgery. General health and disease-specific outcome questionnaires were completed pre- and post-operatively. Costs associated with both functional endoscopic sinus surgery and out-patient visits to a comprehensive asthma clinic were calculated.

RESULTS

A total of 47 patients completed the surveys. The average improvement in Chronic Sinusitis Survey scores following functional endoscopic sinus surgery was 17 per cent. The average reduction in out-patient asthma clinic visits was 50 per cent, which translates to an average cost saving of $1035 Canadian dollars per patient per year.

CONCLUSION

Functional endoscopic sinus surgery is a cost-effective treatment modality for asthmatic patients with chronic rhinosinusitis. This information is important for: the distribution and planning of resources, prioritising health programmes, and establishing practice guidelines.

Bronchial hyperresponsiveness in pediatric rhinitis patients: the difference between allergic and nonallergic rhinitis

BACKGROUND

Numerous studies have examined the relationship of bronchial hyperresponsiveness (BHR) to asthma or allergic rhinitis (AR). However, little is known regarding the association between BHR and nonallergic rhinitis (NAR). This study investigated the prevalence and risk factors of BHR in pediatric patients with rhinitis and analyzed the difference between patients with AR and those with NAR.

METHODS

A total of 227 subjects with rhinitis aged 6-15 years underwent a parental survey and laboratory tests, including skin-prick test and methacholine challenge test. Outcome variables were analyzed in relation to BHR.

RESULTS

The prevalence of BHR was 55.7 and 25.5% in patients with AR and those with NAR, respectively. The persistency of rhinitis, blood eosinophil count, and baseline lung function were significantly associated with BHR in patients with AR, whereas individual or familial medical history, environmental factors, the serum immunoglobulin E level, the number of sensitized allergens, and the wheal size ratio of allergen to histamine did not affect the BHR rate. In multivariate analysis, the persistency of rhinitis was the only significant predictor of BHR in AR patients. However, persistent rhinitis symptoms did not increase the risk of BHR in NAR patients.

CONCLUSION

BHR occurs over two times more frequently in children with AR than in those with NAR. In addition, persistent nasal inflammation appears to increase the risk of BHR only in the presence of atopy.

Topical drug delivery in chronic rhinosinusitis patients before and after sinus surgery using pulsating aerosols

OBJECTIVES

Chronic rhinosinusitis (CRS) is a common chronic disease of the upper airways and has considerable impact on quality of life. Topical delivery of drugs to the paranasal sinuses is challenging, therefore the rate of surgery is high. This study investigates the delivery efficiency of a pulsating aerosol in comparison to a nasal pump spray to the sinuses and the nose in healthy volunteers and in CRS patients before and after sinus surgery.

METHODS

(99m)Tc-DTPA pulsating aerosols were applied in eleven CRSsNP patients without nasal polyps before and after sinus surgery. In addition, pulsating aerosols were studied in comparison to nasal pump sprays in eleven healthy volunteers. Total nasal and frontal, maxillary and sphenoidal sinus aerosol deposition and lung penetration were assessed by anterior and lateral planar gamma camera imaging.

RESULTS

In healthy volunteers nasal pump sprays resulted in 100% nasal, non-significant sinus and lung deposition, while pulsating aerosols resulted 61.3+/-8.6% nasal deposition and 38.7% exit the other nostril. 9.7+/-2.0 % of the nasal dose penetrated into maxillary and sphenoidal sinuses. In CRS patients, total nasal deposition was 56.7+/-13.3% and 46.7+/-12.7% before and after sinus surgery, respectively (p<0.01). Accordingly, maxillary and sphenoidal sinus deposition was 4.8+/-2.2% and 8.2+/-3.8% of the nasal dose (p<0.01). Neither in healthy volunteers nor in CRS patients there was significant dose in the frontal sinuses.

CONCLUSION

In contrast to nasal pump sprays, pulsating aerosols can deliver significant doses into posterior nasal spaces and paranasal sinuses, providing alternative therapy options before and after sinus surgery. Patients with chronic lung diseases based on clearance dysfunction may also benefit from pulsating aerosols, since these diseases also manifest in the upper airways.

Occupational rhinitis and other work-related upper respiratory tract conditions

The nose and upper airways form the initial area of impact for air pollutants and allergens. The development of nasal allergies in the workplace (occupational rhinitis) may herald subsequent development of occupational asthma. Exposure controls, periodic surveillance, and early intervention may circumvent work-related airways disease and prevent unnecessary worker impairment and disability.

Periostin may play a protective role in the development of eosinophilic chronic rhinosinusitis with nasal polyps in a mouse model

OBJECTIVES/HYPOTHESIS

Several genes have been reported to be upregulated in human nasal polyps in previous genetic analyses. Among these genes, periostin is known to be overexpressed in nasal polyps obtained from aspirin-sensitive patients. Using periostin-null mice, we investigated the role of periostin in a murine model of eosinophilic rhinosinusitis with nasal polyps.

STUDY DESIGN

Animal study.

METHODS

Eosinophilic rhinosinusitis was induced in both periostin-null and wild-type mice according to previously established protocols. In brief, ovalbumin (OVA) was used for sensitization and prolonged intranasal stimulation. Staphylococcus aureus enterotoxin B was applied intranasally to develop polyplike lesions. To examine the inflammation and mucosal lesions, hematoxylin and eosin, Sirius red, and Giemsa staining were performed.

RESULTS

There was no definite difference in the maximal mucosal thickness between periostin-null and wild-type mice. In contrast, some parameters of inflammation, including the number of polyplike lesions and mast cells, were aggravated in the periostin-null mice compared to wild type. Eosinophilic infiltration was aggravated in the OVA-stimulated periostin-null mice, compared to OVA-stimulated wild-type mice, whereas there was no apparent difference between wild-type and periostin-null mice challenged with additional S aureus enterotoxin B.

CONCLUSIONS

The loss of periostin appears to enhance polyplike lesion formation and mast cell infiltration in a mouse model of eosinophilic rhinosinusitis with nasal polyps.

Evidence for primary laryngeal inhalant allergy: a randomized, double-blinded crossover study

BACKGROUND

Despite anecdotal reports, no controlled studies to date link allergen exposure with a change in vocal function or dysphonia. The aim of this study was to determine whether allergen exposure in susceptible individuals impairs vocal function.

METHODS

The study was a prospective, double-blind, placebo-controlled study in which subjects serve as their own controls. The participants were 5 inhalant allergic adults with suspected dysphonia from allergies, without evidence of reactive lower airways based on methacholine challenge. All subjects were exposed to 2 experimental conditions in which they were challenged with (1) orally inhaled diluent placebo on 1 day, and (2) orally inhaled allergen on another day. Conditions were randomly ordered across subjects and separated by at least 48 hours. Phonatory threshold pressure (PTP) at the 80th percentile pitch was measured prior to diluent and allergen challenge, and 15 and 60 minutes postchallenge to assess potential change in vocal function after challenge testing.

RESULTS

A repeated measures ANOVA revealed a significant main effect for treatment (allergen vs placebo, p = 0.013) with greater PTP required post-allergen challenge compared to placebo and an effect size of 0.821.

CONCLUSION

A primary causal relationship between allergen exposure and impaired vocal function, as assessed by PTP, was observed in adults with documented allergy independent of asthma or nasal exposure. The current design establishes a safe model for laryngeal inhalant allergen challenge.

Poor asthma control?--then look up the nose. The importance of co-morbid rhinitis in patients with asthma

Many factors can impair asthma control. One which is frequently overlooked is rhinitis. Asthma patients with significant rhinitis are over four times more likely to have poorly controlled asthma than those without. Over 80% of patients with asthma have rhinitis, which may be allergic or inflammatory/non-allergic. Both types of rhinitis share pathophysiological similarities with eosinophilic asthma, cause bronchial hyper-reactivity, and are predisposing factors for the subsequent development of asthma. Nasal allergen challenge in allergic rhinitis results in inflammation in the bronchi as well as the nose, and the reverse is also true. This article reviews briefly the evidence for the link between asthma and rhinitis, advocates looking for rhinitis when patients present with poorly controlled asthma, and provides guidance for the diagnosis and treatment of rhinitis.

Why do we not find polyps in the lungs? Bronchial mucosa as a model in the treatment of polyposis

The link between lower and upper airways has been reported since the beginning of 1800 s. They share the same pseudostratified ciliated columnar epithelium lining and the concept of one airway, one disease is quite well widespread. Nasal polyposis and asthma share basically the same inflammatory process: predominant infiltration of eosinophils, mucus cell hyperplasia, edema, thickened basal membrane, polarization for Th2 cell immune response, similar pro-inflammatory mediators are increased, for example cysteinyl leukotrienes. If the lower and upper airways share a lot of common epithelial structural features so why is the edema in the nasal mucosa able to increase so much the size of the mucosa to the point of developing polyps? The article tries to underline some differences between the nasal and the bronchial mucosa that could be implicated in this aberrant change from normal mucosa to polyps. This paper creates the concept that there are no polyps with the features of nasal polyposis disease in the lower airway and through it is developed the hypothesis of the nasal polyps origin could partially lie on the difference between the upper and lower airway histology.

The airway epithelium: soldier in the fight against respiratory viruses

The airway epithelium acts as a frontline defense against respiratory viruses, not only as a physical barrier and through the mucociliary apparatus but also through its immunological functions. It initiates multiple innate and adaptive immune mechanisms which are crucial for efficient antiviral responses. The interaction between respiratory viruses and airway epithelial cells results in production of antiviral substances, including type I and III interferons, lactoferrin, β-defensins, and nitric oxide, and also in production of cytokines and chemokines, which recruit inflammatory cells and influence adaptive immunity. These defense mechanisms usually result in rapid virus clearance. However, respiratory viruses elaborate strategies to evade antiviral mechanisms and immune responses. They may disrupt epithelial integrity through cytotoxic effects, increasing paracellular permeability and damaging epithelial repair mechanisms. In addition, they can interfere with immune responses by blocking interferon pathways and by subverting protective inflammatory responses toward detrimental ones. Finally, by inducing overt mucus secretion and mucostasis and by paving the way for bacterial infections, they favor lung damage and further impair host antiviral mechanisms.

Added value with extended NO analysis in atopy and asthma

INTRODUCTION

Assessments of the usefulness of exhaled nitric oxide (NO) in the treatment of asthma have given conflicting results. It is not always obvious if atopic status has been tested in these evaluations.

OBJECTIVES

The aim of the study is to use extended NO analysis to characterize subjects from a random sample populations with focus on rhinitis and asthma.

METHODS

Data were extracted from the European Community Respiratory Health Survey II. A subgroup from the Uppsala site that had had their NO measured at multiple flow rates was included (n = 284). The nonlinear model for NO parameters was used. Atopy was defined as having a titre against at least one of the tested allergens ≥0·35 kU l(-1) . Bronchial responsiveness was assessed by methacholine challenge.

RESULTS

Subjects with non-atopic rhinitis or non-atopic asthma could not be separated from healthy subjects regarding NO parameters. There was a gradual increase with atopy in airway diffusion rate (D(aw) NO); healthy subject 8·0 (7·3, 8·8), healthy atopic 8·8 (6·7, 11·5), atopic rhinitis 10·6 (9·0, 12·4) and atopic asthma 11·2 (9·9, 28·3) ml s(-1) [geometrical mean (CI(95%) )]. There was a correlation between bronchial responsiveness and D(aw) NO in atopic rhinitis (r = -0·41, P<0·01), and bronchial responsiveness and airway wall content of NO (C(aw) NO) in atopic asthma (r = -0·56, P<0·001).

CONCLUSION

It is of importance to characterize atopic status when evaluating the association between NO and asthma. Our results indicate that the use of extended NO analysis, with particular attention to D(aw) NO and C(aw) NO, may be useful in monitoring treatment for rhinitis and asthma.

Bronchoalveolar lavage and other methods to define the human respiratory tract milieu in health and disease

During fiber-optic bronchoscopy (FOB), surface sampling of the human respiratory airways and alveolar unit can be done with bronchoalveolar lavage (BAL), plus selective sites can be brushed for cells and transbronchial biopsies made in adjacent tissue. This permits analysis of the respiratory tract's milieu in healthy normals, in those with disease, and in control subjects. These combined procedures have been an established approach for obtaining specimens for research and for clinical assessment for over four decades. However, now new less invasive sampling methods are emerging. This review emphasizes BAL and the cellular and noncellular components recovered in fluid that have contributed to improving knowledge of how the respiratory tree's innate immunity can protect, and how airway structures can become deranged and manifest disease. After a discussion of training for FOB and procedural issues, a spectrum of respiratory diseases studied with BAL is presented, including airway illness (asthma and chronic obstructive pulmonary disease), diffuse interstitial lung diseases [idiopathic pulmonary fibrosis, rheumatoid interstitial lung disease (ILD), granulomatous ILDs], lung infections, lung malignancy, and upper and lower tract airway problems. Some recent studies with exhaled breath condensate analyses are given.

Diagnostic criteria of eosinophilic otitis media, a newly recognized middle ear disease

OBJECTIVE

Eosinophilic otitis media (EOM) is a newly recognized intractable middle ear disease, characterised by the accumulation of eosinophils in middle ear effusion and middle ear mucosa. Since EOM patients show gradual or sudden deterioration of hearing, it is important to properly diagnose EOM and to start adequate treatment for EOM. We aimed to investigate the clinical risk factors of EOM and to establish the diagnostic criteria of EOM.

PATIENTS AND METHODS

We reviewed 138 patients with EOM and 134 age-matched patients with the common type of otitis media with effusion or chronic otitis media as controls. We analyzed the incidence of the following clinical variables in both groups: bilaterality of otitis media, viscosity of middle ear effusion, formation of granulation tissue in the middle ear, response to the treatment for otitis media, deterioration of bone conduction hearing level, and association with other diseases such as bronchial asthma, chronic rhinosinusitis, nasal polyposis, and allergic rhinitis.

RESULTS

A high odds ratio was obtained from an association with bronchial asthma (584.5), resistance to conventional treatment for otitis media (232.2), viscous middle ear effusion (201.6), association with nasal polyposis (42.17), association with chronic rhinosinusitis (26.49), bilaterality (12.93), and granulation tissue formation (12.62). The percentage of patients with EOM who were positive for two or more among the highest four items was 98.55%.

CONCLUSION

A patient who shows otitis media with effusion or chronic otitis media with eosinophil-dominant effusion (major criterion) and with two or more among the highest four items (minor criteria), can be diagnosed as having EOM. Patients with ear symptoms should have the proper diagnosis of EOM using the proposed diagnostic criteria, and then can receive adequate treatment, resulting in prevention of deterioration of hearing and quality of life.

Enhanced susceptibility of nasal polyp tissues to avian and human influenza viruses

BACKGROUND

Influenza viruses bind and infect respiratory epithelial cells through sialic acid on cell surface. Differential preference to sialic acid types contributes to host- and tissue-tropism of avian and seasonal influenza viruses. Although the highly pathogenic avian influenza virus H5N1 can infect and cause severe diseases in humans, it is not efficient in infecting human upper respiratory tract. This is because of the scarcity of its receptor, α2,3-linked sialic acid, in human upper airway. Expression of sialic acid can be influenced by various factors including inflammatory process. Allergic rhinitis and nasal polyp are common inflammatory conditions of nasal mucosa and may affect expression of the sialic acid and susceptibility to influenza infection.

METHODOLOGY/PRINCIPAL FINDING

To test this hypothesis, we detected α2,3- and α2,6-linked sialic acid in human nasal polyp and normal nasal mucosal tissues by lectin staining and infected explants of those tissues with avian influenza viruses H5N1 and seasonal influenza viruses. We show here that mucosal surface of nasal polyp expressed higher level of α2,3- and α2,6-linked sialic acid than normal nasal mucosa. Accordingly, both H5N1 avian influenza viruses and seasonal influenza viruses replicated more efficiently in nasal polyp tissues explants.

CONCLUSIONS/SIGNIFICANCE

Our data suggest a role of nasal inflammatory conditions in susceptibility to influenza infection, especially by avian influenza viruses, which is generally inefficient in infecting human upper airway. The increased receptor expression may contribute to increased susceptibility in some individuals. This may contribute to the gradual adaptation of the virus to human population.