Airway inflammation in asthma and perennial allergic rhinitis. Relationship with nonspecific bronchial responsiveness and maximal airway narrowing

Upper and lower airway interactions in children

PURPOSE OF REVIEW

The aim of the present review was to highlight the interactions between rhinitis, rhinosinusitis and asthma in children and to discuss the most relevant scientific progresses in the pathophysiology and treatment of these combined conditions.

RECENT FINDINGS

Advances in understanding the mechanisms underlying the relationship between upper and lower airways have provided valuable insights into the role of eosinophils in the pathophysiology of inflammatory events and have further delineated the concept of united airway disease. Studies addressed to evaluate the burden of sinonasal system on asthma outcomes showed a parallel severity of upper and lower airway diseases. Histopathology of sinonasal tissue in patients with chronic rhinosinusitis is different in adults and children. Targeted administration of biological agents represents an effective treatment in patients with severe uncontrolled asthma, but specific trials are awaited in children with chronic sinonasal disease.

SUMMARY

Allergic rhinitis and rhinosinusitis are important comorbidities in patients with asthma. Improved knowledge of pathogenic mechanisms of inflammation and remodelling in the sinonasal system and the lung has led to new therapeutic approaches in patients with united airway disease and opened interesting perspectives for personalized drug therapies.

Blood eosinophil related to maternal allergic rhinitis is associated with the incidence of allergic rhinitis in offspring: COCOA study

OBJECTIVE

The identification of allergic rhinitis (AR) in early life is important for the target of intervention. AR is caused by various environmental factors, including house dust mites. We investigated the relationship between the Dermatophagoides farinae (Der f)-IgE and eosinophil in mothers with AR at delivery and the eosinophil levels and AR incidence in children.

METHODS

The study participants were 983 mother-child pairs from the COhort for Childhood Origin of Asthma and Allergic Diseases. AR was diagnosed by a doctor at delivery in mother and at 3 years of age in offspring. The association between eosinophil level and AR was assessed using logistic regression analysis.

RESULTS

The Der f-IgE level in mother having AR at delivery was associated with the mother's eosinophil level, and the mother's eosinophil level was associated with the child's eosinophil level both at age 1 and 3. The risk of AR at age 3 in children was increased according to increased eosinophil levels in mothers at delivery and in children both aged 1 and 3 years (adjusted odds ratio [aOR] and 95% confidence interval [CI]: 2.57 [1.14-5.78], 2.28 [1.02-5.13], respectively). The risk of childhood AR at the age of 3 is increased when both mothers and children have high eosiniophils (aOR and 95% CI: 2.62 [1.01-6.79], 1.37 [0.98-1.91]).

CONCLUSIONS

Der f-IgE in mothers at delivery was related to eosinophil levels in mothers with AR and higher level of eosinophils in both mother and children was associated with the increased risk of AR incidence at the first 3 years of life of children.

Airway hyperresponsiveness and inflammation in Japanese patients with human immunodeficiency virus 1 infection

INTRODUCTION

Despite the growing population of long-term survivors with human immunodeficiency virus 1 (HIV) exhibiting asthma-like features worldwide, the pathogenesis underlying airway hyperresponsiveness (AHR) and airway inflammation remains unclear. We aimed to investigate AHR and airway inflammation in an HIV-infected Japanese population.

METHODS

Of 94 Japanese participants, 10 HIV-infected participants with asthma were excluded from the study. We compared the characteristics of HIV-infected (n = 34) and non-HIV-infected participants (n = 50). Eosinophilic, neutrophilic, mixed (eosinophilic and neutrophilic), and paucigranulocytic airway inflammatory phenotypes were classified based on induced sputum characteristics.

RESULTS

The prevalence of AHR in HIV-infected participants (32.4%) was significantly higher than that in their non-HIV-infected counterparts (10.0%) (P = 0.0213). The multivariate nominal logistic regression analysis revealed HIV as an independent risk factor for AHR. HIV-infected participants were significantly more likely to have a neutrophilic airway inflammatory phenotype than non-HIV-infected participants (P = 0.0358). Furthermore, HIV-infected participants with AHR demonstrated a significant correlation between AHR levels and the percentage of sputum neutrophils (r = -0.65, P = 0.0316). The percentage of sputum neutrophils was negatively associated with the blood CD4 cell count (r = -0.66, P = 0.0266).

CONCLUSIONS

We observed the high prevalence of AHR and neutrophilic airway inflammatory phenotype in Japanese participants with stable HIV infection. Our findings provide insight into the mechanisms of AHR and may facilitate the development of novel treatment for individuals with AHR and HIV infection.

The correlation between FeNO and nNO in allergic rhinitis and bronchial asthma

This study aimed to evaluate the correlation between fractional exhaled nitric oxide (FeNO) and nasal nitric oxide (nNO) in allergic rhinitis (AR) and patients with or without bronchial asthma (BA).A total of 90 patients who were diagnosed with persistent AR (AR group, n = 30), BA (BA group, n = 30), or allergic rhinitis with bronchial asthma (AR-BA) (AR-BA group, n = 30), were enrolled in this study, along with 30 healthy adult volunteers (control group, n = 30). The participants were further divided into 2 groups based on the results of a skin-prick test (SPT): a highly atopic group (SPT = 3+ and above) and a moderately atopic group (SPT = 2+ and below). All participants underwent FeNO and nNO measurement, an absolute blood eosinophil count, total serum immunoglobulin measurement, and horizontal baseline lung capacity determination.The results showed that the FeNO levels in the 3 observation groups were significantly higher than those in the control group (P < .01), and in the BA group they were significantly higher than in the AR-BA group (P < .01). The levels of nNO in both the AR group and the AR-BA group were higher than those in the control group and the BA group (P < .01), but there was no significant difference between the AR group and the AR-BA group (P > .05). The levels of nNO in the BA group were also significantly different from those in the control group (P < .01).FeNO and nNO are positively correlated with the degree of AR in patients with BA; therefore, nNO levels can be used as an inflammatory marker of AR in patients with BA. FeNO can also be used as an inflammatory marker of AR in patients complicated with BA as a warning indicator of asthma.

Janus looks both ways: How do the upper and lower airways interact?

Our understanding of the relationship between the upper and lower airways has greatly increased as a consequence of epidemiologic and pharmacologic studies. A consistent body of scientific evidence supports the concept that rhinitis, rhinosinusitis and asthma may be the expression of a common inflammatory process, which manifests at different sites of the respiratory tract, at different times. This paradigm states that allergic reactions may begin at the local mucosa, but tend to propagate along the airway. Central to the allergic diathesis is the eosinophil and its interaction with the airway epithelium. The implications of the interplay between upper and lower airway are not only academic, but also important for diagnostic and therapeutic reasons. Furthermore, there is significant overlap in symptomatology and pathophysiology for childhood sleep disordered breathing (SDB) and asthma. Recent evidence supports an association between these two conditions, but causality has not been demonstrated. Regardless, it is important to recognize the overlap and evaluate for the other condition when one is present. In children with poorly controlled asthma, the presence of SDB may significantly contribute to asthma morbidity and, as such, should be actively excluded. On the other hand, clinical evaluation for asthma should be considered in children with SDB. Future robust longitudinal research is needed to explore the association between upper and lower airway diseases using objective measures in children.

Assessing the health impact of interventions for baker's allergy and asthma in supermarket bakeries: a group randomised trial

PURPOSE

To assess the impact of an intervention for baker's allergy and asthma in supermarket bakeries.

METHODS

A group randomised trial conducted in 31 bakeries (n = 337 bakers) that were randomly assigned to one of two intervention groups (n = 244 bakers) and a control group (n = 93 bakers). Health data collected prior to and 1-year after the intervention included information obtained from an ECRHS questionnaire; tests for atopy and serum-specific IgE to cereal flours; fractional exhaled nitric oxide (FeNO). Data from the two intervention groups were combined to form one intervention group for purposes of the statistical analysis.

RESULTS

At 1 year of follow-up, the incidence and level of decline of work-related ocular-nasal and chest symptoms, sensitisation status and elevated FeNO (FeNO > 25 ppb) was similar in both intervention and control groups. The mean FeNO difference was also similar across both groups (2.2 ppb vs 1.7 ppb, p = 0.86). In those with FeNO > 25 ppb at baseline, the decline was greater in the intervention compared to control group (16.9 ppb vs 7.7 ppb, p = 0.24). Multivariate logistic regression models (adjusting for smoking, baseline sensitisation to cereal flour, baseline FeNO > 25 ppb) did not demonstrate an appreciable FeNO decline (≥ 10%) in the intervention compared to control group. However, stratification by the presence of work-related ocular-nasal symptoms in bakers at baseline demonstrated a significant FeNO decline (≥ 10%) in the intervention compared to the control group (OR 3.73, CI 1.22-11.42).

CONCLUSION

This study demonstrates some evidence of an intervention effect on FeNO 1 year after an intervention, particularly in bakers with work-related ocular-nasal symptoms.

The emerging role of mast cell proteases in asthma

It is now well established that mast cells (MCs) play a crucial role in asthma. This is supported by multiple lines of evidence, including both clinical studies and studies on MC-deficient mice. However, there is still only limited knowledge of the exact effector mechanism(s) by which MCs influence asthma pathology. MCs contain large amounts of secretory granules, which are filled with a variety of bioactive compounds including histamine, cytokines, lysosomal hydrolases, serglycin proteoglycans and a number of MC-restricted proteases. When MCs are activated, e.g. in response to IgE receptor cross-linking, the contents of their granules are released to the exterior and can cause a massive inflammatory reaction. The MC-restricted proteases include tryptases, chymases and carboxypeptidase A3, and these are expressed and stored at remarkably high levels. There is now emerging evidence supporting a prominent role of these enzymes in the pathology of asthma. Interestingly, however, the role of the MC-restricted proteases is multifaceted, encompassing both protective and detrimental activities. Here, the current knowledge of how the MC-restricted proteases impact on asthma is reviewed.

Potent ameliorating effect of Hypoxia-inducible factor 1α (HIF-1α) antagonist YC-1 on combined allergic rhinitis and asthma syndrome (CARAS) in Rats

Recent studies have implicated that Hypoxia-inducible factor 1α (HIF-1α) plays an integral role in the pathogenesis of allergic rhinitis and asthma. In the present study, we showed that HIF-1α antagonist YC-1, 3-(5-hydroxymethyl-2-furyl)-1-benzylindazole, elicited a potent allergy-ameliorating effect in a rat model of ovalbumin (OVA)-sensitized combined allergic rhinitis and asthma syndrome (CARAS). We revealed that YC-1 administration markedly impaired the total number and percentage of eosinophil in bronchoalveolar lavage fluid (BAL Fluid) of the rats, suggesting that YC-1 might attenuate lung and nasal mucosal inflammation in OVA-sensitized rats. Moreover, histological examination found that OVA-induced pathological alterations were evidently attenuated following YC-1 administration. In addition, immunohistochemistrial analysis indicated that YC-1 treatment decreased the expression of HIF-1α in rat lungs and nasal mucosa. Notably, Nuclear factor kappa B (NF-κB) p65 and Peroxisome proliferator-activated receptor α (PPARα), two important regulators of inflammatory responses, were also significantly down-regulated following YC-1 administration. Real-time PCR analysis confirmed that YC-1 impaired the expression of HIF-1α, NF-κB and PPARα in CARAS model. These findings together indicated that YC-1 exerted remarkable anti-allergic effects through the modulation of inflammatory pathways, implying that YC-1 may potentially serve as a novel anti-CARAS medicine in clinical patients.

Lung CD200 Receptor Activation Abrogates Airway Hyperresponsiveness in Experimental Asthma

In allergic asthma, homeostatic pathways are dysregulated, which leads to an immune response toward normally innocuous antigens. The CD200-CD200 receptor pathway is a central regulator of inflammation, and CD200 expression was recently found to be down-regulated in circulating leukocytes of patients with asthma. Given the antiinflammatory properties of CD200, we investigated whether local delivery of recombinant CD200 (rCD200) could reinstate lung homeostasis in an experimental model of asthma. Brown Norway rats were sensitized with ovalbumin (OVA) and alum. rCD200 was intratracheally administered 24 hours before OVA challenge, and airway responsiveness to methacholine was measured 24 hours after the allergen challenge. Inflammation was also assessed by measuring cell recruitment and cytokine levels in bronchoalveolar lavages, as well as lung and draining lymph node accumulation of dendritic cells (DCs) and T cells. In sensitized rats, rCD200 abolished airway hyperresponsiveness, whereas the sham treatment had no effect. In addition, rCD200 strongly reduced OVA-induced lung accumulation of myeloid DCs, CD4(+) T cells, and T helper type 2 cells. This was associated with a strong reduction of OVA-induced IL-13 level and with an increase of IL-10 in supernatants of bronchoalveolar lavages. Lung eosinophilia and draining lymph node accumulation of myeloid DCs and T cells were not affected by rCD200. Overall, these data reveal that rCD200 can inhibit airway hyperresponsiveness in a model of asthma by a multistep mechanism associated with local alterations of the T cell response and the cytokine milieu.

Can we predict allergen-induced asthma in patients with allergic rhinitis?

BACKGROUND

A high percentage of patients with allergic rhinitis (AR) exhibit signs of bronchial hyperreactivity (BHR), and approximately 30% may develop asthma later in life.

OBJECTIVE

The aim of this study was to identify predictors for allergen-induced asthma in patients with AR.

METHODS

Hundred patients with AR selected by public posting and 20 healthy controls were enrolled. Twenty-three patients with concomitant physician-diagnosed asthma and four with a negative allergy test were excluded from further analysis. The remaining 73 subjects with AR underwent bronchial allergen provocation (BAP), which is considered the gold standard for the diagnosis of clinically relevant allergen-specific asthma. The following parameters were measured to explore predictors for an early and late asthmatic response (EAR and LAR): standardised questionnaire, skin prick test (SPT), total IgE, specific IgE to grass pollen, FEV1, PD20FEV1 methacholine, exhaled nitric oxide (eNO) and eosinophils.

RESULTS

Early asthmatic reaction was equally distributed between patients with and without signs of possible asthma by questionnaire (56.8% vs. 48.3%). The following cut-off values showed the best combination of sensitivity and specificity for an EAR: specific IgE grass pollen 18.5 kU/L (AUC 0.83), SPT 8.5 mm (AUC 0.76), total IgE 95.5 kU/L (AUC 0.73), FEV1 102.4% (AUC 0.69), PD20FEV1 methacholine 1.67 mg (AUC 0.74), eNO 18.05 ppB (AUC 0.64) and eosinophils 115/mm(3) (AUC 0.58).

CONCLUSIONS AND CLINICAL RELEVANCE

There is a considerable discordance between reported asthma signs and diagnosed disease by BAP. Simple measurement of allergen-specific IgE for grass pollen was the best predictor of allergen-induced asthma in patients with AR.

Nasobronchial interaction

Upper and lower airways can be considered as a unified morphofunctional unit. In this paper, nasobronchial interactions are evaluated based on literature.To discuss nasobronchial interactions, literature review from PubMed since 1982 is evaluated. Data base was including the terms “nasobronchial interaction, nasal and bronchial”. Asthma and rhinosinusitis may be associated with environmental factors and immunological predisposition. Treatment of rhinosinusitis may decrease asthma exacerbations. It was concluded that “one airway, one disease”-concept may be accepted when considering naso-bronchial interaction. Asthma treatment should also mean treating the nose as good as treating patients with nasal symptoms. To reach the succesful results ıt should be associated with evaluation of lung functions.

Evaluation of vascular endothelial growth factor-A and Endostatin levels in induced sputum and relationship to bronchial hyperreactivity in patients with persistent allergic rhinitis monosensitized to house dust

BACKGROUND

Studies about the pathogenesis of bronchial hyperreactivity (BHR) in patients with persistent allergic rhinitis (PAR) and its relationship with lower airway remodeling are extremely limited.

OBJECTIVE

This study evaluated bronchial vascular remodeling via the measurement of angiogenic factor, vascular endothelial growth factor-A (VEGF-A), and anti-angiogenic factor, Endostatin, and evaluated their relationship with BHR in patients with PAR.

METHODS

The study group consisted of 30 patients with PAR monosensitized to house dust mites and 14 non-allergic healthy controls. All subjects underwent induced sputum and methacholine (M) bronchial provocation tests. VEGF-A and Endostatin levels were measured by ELISA in induced sputum supernatants.

RESULTS

The percentages of eosinophils in induced sputum were significantly increased in patients with PAR compared with healthy controls. There were no significant differences between patients with PAR and healthy controls in terms of levels of VEGF (37.9pg/ml, min-max: 5-373pg/ml vs. 24.9, min-max: 8-67pg/ml, p=0.8 respectively), Endostatin (532.5pg/ml, min-max: 150-2125pg/ml vs. 644, min-max: 223-1123pg/ml, p=0.2 respectively) and VEGF/Endostatin ratio (0.057 vs. 0.045, p=0.8 respectively). In addition, there were no significant differences between patients who are BHR positive (n=8), or negative to M (n=22) in terms of levels of VEGF, Endostatin and VEGF/Endostatin ratio and no correlations among value of PD20 to M and levels of VEGF, Endostatin and VEGF/Endostatin ratio.

CONCLUSION

We conclude that VEGF-A and Endostatin did not differ between patients with PAR and healthy controls regardless of BHR to M.

Full blood count parameters for the detection of asthma inflammatory phenotypes

BACKGROUND

In asthma, the airway inflammatory phenotype influences clinical characteristics and treatment response. Although induced sputum is the gold standard test for phenotyping asthma, a more accessible method is needed for clinical practice.

OBJECTIVE

To investigate whether white blood cell counts and/or their derived ratios can predict sputum eosinophils or neutrophils in uncontrolled asthma.

METHODS

This cross-sectional study evaluated 164 treated but uncontrolled asthmatic patients with sputum induction and blood collection. Receiver-operating characteristic (ROC) curves were used to assess the relationship between blood and sputum parameters.

RESULTS

There was a significant positive relationship between blood eosinophil parameters and the percentage of sputum eosinophil count. A weak but significant correlation was found between sputum neutrophil percentage and blood neutrophil percentage (r = 0.219, P = 0.005). ROC curve analysis identified that blood eosinophil percentage count was the best predictor for eosinophilic asthma, with an area under the curve (AUC) of 0.907 (P < 0.001). The optimum cut-point for blood eosinophil percentage was 2.7%, and this yielded a sensitivity of 92.2% and a specificity of 75.8%. The absolute blood eosinophil count was also highly predictive with an AUC of 0.898 (P < 0.0001) at a blood eosinophil cut-off of 0.26 × 10(9) /L. The blood eosinophil/lymphocyte ratio (ELR) and eosinophil/neutrophil ratio (ENR) were increased in eosinophilic asthma, and the neutrophil/lymphocyte ratio (NLR) was increased in neutrophilic asthma. Neutrophilic asthma could also be detected by blood neutrophil percentages and NLR, but with less accuracy.

CONCLUSIONS AND CLINICAL RELEVANCE

Blood eosinophil counts and derived ratios (ELR and ENR) can accurately predict eosinophilic asthma in patients with persistent uncontrolled asthma despite treatment. Blood neutrophil parameters are poor surrogates for the proportion of sputum neutrophils. Blood counts may be a useful aid in the monitoring of uncontrolled asthma.

Mannitol versus hypertonic saline

Eosinophilic asthma phenotype predicts good response to corticosteroids and associates to asthmatic exacerbations. Sputum induction by hypertonic saline (HS) inhalation is technically demanding. Bronchial hyperresponsiveness (BHR) to osmotic agents indirectly mirrors active airway inflammation. We compared the safety and ability of HS and mannitol to induce sputum and measure BHR. We evaluated the stability of inflammatory phenotypes. We studied 35 non-smoking asthmatics randomized to undergo HS and mannitol challenges on 2 days 1 week apart. Sputum was sampled for cell analysis and phenotyped as eosinophilic (≥3% eosinophils) and non-eosinophilic (<3%) asthma. Nineteen subjects had BHR to mannitol and nine of them also had BHR to HS. Drops in forced expiratory volume in 1 s were higher from HS challenge than from mannitol challenge. Adequate sputum samples were obtained from 80% subjects (68% mannitol and 71% HS). Eosinophils and macrophages from both challenges correlated. Neutrophils were higher in sputum from HS. Ninety percent samples were equally phenotyped with HS and mannitol. Fractional exhaled nitric oxide, sputum eosinophils and BHR correlated in both challenges. HS and mannitol showed similar capacity to produce valuable sputum samples. BHR to both osmotic stimuli partially resembled airway eosinophilic inflammation but mannitol was more sensitive than HS to assess BHR. Eosinophilic phenotype remained stable in most patients with both stimuli.

Bronchial inflammation in seasonal allergic rhinitis with or without asthma in relation to natural exposure to pollen allergens

BACKGROUND

Nasal inflammation in allergic rhinitis enhances bronchial Th2 driven inflammation and development of asthma. We assessed bronchial inflammation induced by natural allergen exposure during pollen season in patients with pollinosis with or without asthma to show the intensity of inflammation in asthma and rhinitis and possible persistence of inflammation in periods without allergen exposure.

METHODS

Sputum was induced in 52 patients with seasonal allergic rhinitis without asthma, 38 patients with seasonal allergic rhinitis and seasonal asthma and 23 healthy volunteers. Sampling was performed 6-8 weeks before the expected beginning of symptoms, during symptomatic period and 6-8 weeks after the end of symptoms. Sputum ECP was measured by means of chemi-luminiscent immunometric assay and sputum cell counts were assessed by classical staining and immunocytochemistry.

RESULTS

Sputum eosinophils were on the whole higher in both asthma and rhinitis compared to controls (p<0.001, p=0.003). The rise of eosinophils during pollen season compared with values out of pollen season was significant in asthma (classical staining) (p=0.014) and slightly apparent in rhinitis (immunocytochemistry) (p=0.073). The seasonal rise of sputum ECP was observed only in rhinitis (p=0.006).

CONCLUSIONS

Inflammation of the lower airway in patients with allergic rhinitis with and without asthma has been confirmed by means of both sputum eosinophil count and sputum ECP level. Persistent inflammation of lower airway in periods without allergen exposure was proven in seasonal asthma. This may have implications for the therapy of seasonal allergic rhinitis with and without asthma in terms of promoting long-term anti-inflammatory treatment.

Correlation of exhaled nitric oxide, nasal nitric oxide and atopic status: A cross-sectional study in bronchial asthma and allergic rhinitis

Objective:

Exhaled nitric oxide (FE_NO) and nasal nitric oxide (n NO) measurement is an area of ongoing research in the study of airway inflammation. The atopic status is known to influence the levels of FE_NO and n NO. This study was undertaken to study the relationship between nitric oxide measurements in bronchial asthma and allergic rhinitis along with their correlation with atopic profile of Indian population.

Materials and Methods:

Ninety subjects were recruited for the study comprising of 25 each of bronchial asthma (BA), allergic rhinitis (AR), bronchial asthma with allergic rhinitis (BA-AR) and 15 healthy controls. These were assessed for atopy and exhaled breath analysis of nitric oxide. The measurements of FE_NO and n NO levels were done using NIOX chemiluminescence analyzer. Atopy was assessed by skin prick testing (SPT) against 58 common aero-allergens and subjects with ≥1 positive SPT were labeled as atopic.

Results:

The BA-AR and BA groups had higher FE_NO levels in comparison to the control (P < 0.05) and AR group (P < 0.05). The AR and BA-AR groups had higher n NO levels compared to the control group (P < 0.05) and BA group (P < 0.05). The increasing FE_NO levels significantly correlated with the increase in the number of allergen sensitization in patients suffering from BA-AR (P < 0.05). However, the BA group showed a weaker positive correlation (P = 0.07).

Conclusion:

FE_NO is a non-invasive marker of airway inflammation. Also, FE_NO levels correlate with presence and degree of atopy in BA and AR. Simultaneously, n NO could be a surrogate marker of rhinitis.

The role of small airway disease in asthma

PURPOSE OF REVIEW

This review provides an update on the importance of the peripheral 'small' airways in asthma. As the small airways account for less than 10% of total airway resistance, thus having little impact on standard lung function measures such as forced expiratory volume and peak flow, they have been referred to as the 'silent zone'.

RECENT FINDINGS

The study has revealed that small airway involvement is present in all stages of asthmatic disease, being related to important clinical phenotypes such as nocturnal asthma, exercise-induced asthma, and difficult-to-control asthma, including those with the risk of repeated asthma exacerbations. Uncontrolled small airway inflammation is related to airway remodeling and progression of the disease, with a more rapid decline in the lung function. Moreover, studies on both children and adults have shown that the involvement of the small airways represents a crucial step in asthma development. New tools have been developed and old tools have been refined, providing an opportunity to better understand small airway inflammation and dysfunction.

SUMMARY

Small airway inflammation is present in all stages of asthmatic disease and plays an important role in many key clinical conditions/phenotypes. In order to control the disease, we need to target small airway inflammation, which is not only difficult to reach by standard inhaled medications but also to some extent different. A better understanding of the important role small airways are playing in asthma will show that the 'silent zone' is by far not silent at all.

Prevalence and clinical relevance of allergic rhinitis in patients with classic asthma and cough variant asthma

BACKGROUND

A clinically relevant relationship between classic asthma and allergic rhinitis has been reported. However, the possible link between cough variant asthma (CVA) and allergic rhinitis remains unknown.

OBJECTIVES

To clarify the prevalence and clinical relevance of perennial allergic rhinitis or seasonal allergic rhinitis in CVA patients compared to classic asthma patients.

METHODS

We retrospectively studied adult patients with classic asthma (n = 190) and those with CVA (n = 83). The prevalence of perennial allergic rhinitis or seasonal allergic rhinitis and associations of concomitant perennial or seasonal allergic rhinitis with asthma severity, forced expiratory volume in 1 s (% predicted), fractional exhaled nitric oxide (FeNO) levels, and eosinophil proportions in sputum and blood were analyzed in the two groups.

RESULTS

The prevalence of perennial allergic rhinitis and/or seasonal allergic rhinitis was significantly higher in classic asthma patients than in CVA patients (all p < 0.05). Concomitant perennial allergic rhinitis was associated with higher FeNO levels and eosinophil proportions in sputum and blood in classic asthma patients (p = 0.035, p = 0.036, and p = 0.008, respectively) and with higher asthma severity, FeNO levels, and sputum eosinophil proportions in CVA patients (p = 0.031, p = 0.007, and p = 0.010, respectively). Concomitant seasonal allergic rhinitis was only associated with higher sputum eosinophil proportions in CVA patients with active rhinitis symptoms during the sensitized pollen season (p = 0.025).

CONCLUSIONS

Perennial allergic rhinitis may be relevant for CVA patients as well as classic asthma patients by consistently augmenting eosinophilic lower airway inflammation.

Eosinophilic airway inflammation and airway hyperresponsiveness according to aeroallergen sensitization pattern in patients with lower airway symptoms

Purpose

Sensitization to specific allergens may be important in the development of allergic airway inflammation and airway hyperresponsiveness (AHR). We evaluated the effect of specific aeroallergen sensitization on eosinophilic airway inflammation and AHR.

Methods

We reviewed retrospectively the clinical data of subjects who underwent skin prick tests to aeroallergens, induced sputum analysis, and methacholine bronchial provocation tests to evaluate lower airway symptoms as well as analyzed the associations between the pattern of aeroallergen sensitization and sputum eosinophilia or AHR.

Results

Of the 1,202 subjects be enrolled, 534 (44.4%) were sensitized to at least one aeroallergen in skin tests. AHR was demonstrated in 23.5% and sputum eosinophilia in 38.8%. Sputum eosinophilia was significantly associated with sensitization to perennial allergens (OR, 1.9; 95% CI, 1.4-2.5), house dust mite (OR, 1.7; 95% CI, 1.3-2.3), dog (OR, 1.9; 95% CI, 1.1-3.3), and cat (OR, 2.1; 95% CI, 1.4-3.4). AHR was associated with sensitization to perennial allergens (OR, 2.7; 95% CI, 2.0-3.7), house dust mite (OR, 2.2; 95% CI, 1.6 3.2), Alternaria (OR, 2.3; 95% CI, 1.2-4.7), and cat (OR, 2.7; 95% CI, 1.7-4.3). Sensitization to more perennial allergens increased the risk for sputum eosinophilia and AHR. There was no relationship with individual seasonal allergens.

Conclusion

The development of airway eosinophilic inflammation and AHR in an adult Korean population was associated with sensitization to perennial allergens rather than seasonal allergens.

Rhinitis patients with sputum eosinophilia show decreased lung function in the absence of airway hyperresponsiveness

Purpose

Sputum eosinophilia is observed frequently in patients with rhinitis. Sputum eosinophilia in patients with non-asthmatic allergic rhinitis has been suggested to be related to nonspecific airway hyperresponsiveness (AHR). However, the clinical significance of sputum eosinophilia in patients with non-asthmatic rhinitis without AHR has not been determined. We conducted a retrospective study examining the influence of sputum eosinophilia in patients with non-asthmatic rhinitis without AHR on pulmonary function and expression of fibrosis-related mediators.

Methods

Eighty-nine patients with moderate-to-severe perennial rhinitis without AHR were included. All underwent lung function tests (forced expiratory volume in 1 second [FEV1] and forced vital capacity [FVC]), skin tests to inhalant allergens, methacholine bronchial challenge tests, and hypertonic saline-induced sputum to determine eosinophil counts. Sputum mRNA levels for transforming growth factor-β (TGF-β), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP-1) were also examined. Patients were divided into two groups according to the presence of sputum eosinophilia (≥3%, eosinophilia-positive [EP] and <3%, eosinophilia-negative [EN] groups).

Results

FEV1 was significantly lower (P=0.04) and FEV1/FVC tended to be lower (P=0.1) in the EP group than in the EN group. In sputum analyses, the MMP-9 mRNA level (P=0.005) and the ratio of MMP-9 to TIMP-1 expression (P=0.01) were significantly higher in the EP group than in the EN group. There was no significant difference in TGF-β mRNA expression between the two groups.

Conclusions

Sputum eosinophilia in patients with moderate-to-severe perennial rhinitis without AHR influenced FEV1 and the expression pattern of fibrosis-related mediators.

Evaluation of Vascular Endothelial Growth Factor A and Endostatin Levels in Induced Sputum and Relationship to Bronchial Hyperreactivity in Patients with Seasonal Allergic Rhinitis

Background

Studies about the pathogenesis of bronchial hyperreactivity (BHR) in patients with allergic rhinitis (AR) and its relationship with lower airway remodeling are extremely limited. In this study, bronchial vascular remodeling and its relationship with BHR were evaluated by measurement of vascular endothelial growth factor A (VEGF-A) and endostatin in patients with seasonal AR (SAR).

Methods

The study group consisted of 30 patients with SAR (positive skin test to grass pollens) and 14 healthy controls. Induced sputum and bronchial provocation test (BPT) to methacholine (M) were performed in season. VEGF-A and endostatin levels were measured by ELISA in induced sputum supernatant.

Results

The percentages of eosinophils in induced sputum were significantly increased in BHR+ patients (n = 10) with SAR compared with BHR– patients (n = 20) with SAR (p < 0.001). There was no correlation between eosinophils and provocative concentration of M required to produce a 20% decrease in forced expiratory volume in 1 second. The levels of VEGF-A were significantly higher in SAR patients with BHR than in SAR patients without BHR and healthy controls (respectively, p = 0.014 and p = 0.04). The levels of endostatin were significantly lower in SAR patients with BHR than in SAR patients without BHR and healthy controls (respectively, p = 0.020 and p = 0.014). The ratio of VEGF-A/endostatin was significantly higher in SAR patients with BHR than in SAR patients without BHR and healthy controls (respectively, p = 0.009 and p = 0.019).

Conclusion

In this first study comparing the VEGF-A and endostatin levels of patients with SAR in sputum supernatant, the presence of BHR was shown to be associated with the vascular component of remodeling “angiogenesis.”

Asthma and rhinitis: what is the relationship?

PURPOSE OF REVIEW

Asthma and rhinitis are commonly associated and they influence their respective control. New observations have contributed to better understand how to assess those conditions and how they influence each other.

RECENT FINDINGS

Recent studies found that not only the intensity, but also the duration of rhinitis could be correlated with the development of asthma and possibly its remission. The measure of exhaled nitric oxide (FeNO) has been used to show the presence of lower airway inflammation in rhinitic patients, with or without asthma. Furthermore, it has been shown that allergic rhinitis could affect asthma control in children as in adults, and consequently suggested that allergic rhinitis and asthma should be concomitantly approached in regard to their diagnosis and treatment. Additional observations showed improvements in various asthma outcomes with the treatment of rhinitis.

SUMMARY

These new data confirm the strong link between asthma and rhinitis, the importance of their interactions, and the need to identify and treat rhinitis adequately in asthmatic patients.

Spirometric parameters and levels of interferon gamma and IL-5 in induced sputum from patients with allergic rhinitis or asthma

BACKGROUND

This study was designed to analyze spirometric parameters and cytokine (interferon [IFN] gamma and IL-5) levels in induced sputum from patients with asthma or allergic rhinitis (AR) and nonatopic subjects.

METHODS

Thirty-three subjects aged 18-60 years were enrolled in the present study. Eight patients had asthma without AR symptoms, 16 had AR without asthma symptoms or history, and both groups had positive skin-prick test (SPT) to aeroallergens. The nine remaining subjects were healthy nonatopic subjects with negative SPT to aeroallergens. Spirometry was performed by evaluating the forced vital capacity (FVC), forced expiratory volume in the 1st second (FEV(1)), and forced expiratory flow between 25 and 75% (FEF(25-75)) of FVC before and after bronchodilator use. Induced sputum samples were also collected for measuring cytokine (IFN-gamma and IL-5) levels by enzyme-linked immunosorbent assay.

RESULTS

Significant pre- and postbronchodilator change was observed only for FEV(1) with higher variation values in asthmatic subjects compared with patients with AR (p < 0.05) and nonatopic subjects (p < 0.01). There was no significant difference in pre- and postbronchodilator spirometric parameters among the three groups, although asthmatic patients showed lower prebronchodilator FEF(25-75) values (p = 0.065). IL-5 levels were higher in induced sputum from patients with asthma and AR compared with nonatopic subjects (p = 0.020 and p = 0.032, respectively), but IFN-gamma levels showed no significant difference between the groups.

CONCLUSION

Spirometric measurements were not able to show any occurrence of bronchial constriction in patients with AR, but predominant IL-5 levels in induced sputum from these patients reinforce the role of Th2-type immune response in lower respiratory airways that could contribute to the concept of "one airway, one disease."

Asthma in patients with Japanese cedar pollinosis

Japanese cedar pollen is the most common causative allergen for seasonal allergic rhinitis (AR) in Japan. More commonly known as Japanese cedar pollinosis, it occurs in spring causing the typical symptoms of seasonal AR, such as sneezing, rhinorrhea, nasal obstruction, nasal itching, and itching of the eyes. Previous reports indicate that the prevalence of Japanese cedar pollinosis among Japanese was 26.5%. According to a more recent questionnaire-based survey, the prevalence of Japanese cedar pollinosis in patients with adult asthma might be up to 30% to 50%, suggesting higher rates than that previously reported. Moreover, 30% to 60% of adult asthmatic patients with concomitant pollinosis have exacerbations of their asthma symptoms during the Japanese cedar pollen season. These findings suggest that concomitant Japanese cedar pollinosis may be an aggravating factor in patients with asthma. As with other pollens, such as grass and birch, Japanese cedar pollen was shown to be a trigger factor for worsening asthma. In clinical practice, a number of Japanese patients with asthma are monosensitized to Japanese cedar pollen but not to other antigens. Further studies are needed to elucidate the mechanisms of Japanese cedar pollen in inducing and in exacerbating asthma. The presence of concomitant AR is often associated with the difficulty in asthma control. However, there has been a controversy whether treating concomitant AR by intranasal corticosteroid would produce better asthma-related outcomes in patients with asthma and AR. The effect of treating concomitant cedar pollinosis by intranasal corticosteroids on asthma control in patients with asthma and cedar pollinosis also remains unknown. Certain systemic treatments, such as leukotriene receptor antagonist and anti-IgE monoclonal antibody, are supposed to reduce the symptoms of both asthma and AR in patients with asthma and concomitant AR. In conclusion, Japanese cedar pollinosis is often associated with exacerbations of asthma. Further investigations are expected to elucidate the precise impact and mechanisms of Japanese cedar pollinosis in asthma.

Recent developments in United airways disease

The nose and lung are both part of the respiratory tract. Often the diseases affecting the nose and/or the bronchi are treated separately. However, in recent years, numerous studies have highlighted the fact that the respiratory system is a single entity and the concept of "united airway disease" has become more and more important. The unity of the respiratory tract is confirmed both from a morphological and from a functional point of view. Nevertheless, this concept is also confirmed for the respiratory immune system, innervation and vascularization interesting all along the tract, from the nose to the bronchioles. When treating rhinitis, it is often necessary to assess the presence of asthma. Patients with sinusitis should be evaluated for a possible concomitant asthma. Conversely, patients with asthma should always be evaluated for possible nasal disease. The medications that treat nasal diseases appear to be useful in improving control of asthma and in reducing bronchial hyperresponsiveness as well. Physicians should always keep these notions in mind, and evaluate and treat respiratory diseases taking into account the unity of the respiratory tract.

Alveolar mast cells shift to an FcεRI-expressing phenotype in mild atopic asthma: a novel feature in allergic asthma pathology

BACKGROUND

A unique feature of alveolar mast cells is their low high-affinity IgE receptor (FcεRI) expression. Recent discoveries in uncontrolled asthma suggest that the appearance of FcεRI-expressing alveolar mast cells may be a novel disease-specific feature of allergic asthma. This study investigates whether increased FcεRI-expressing alveolar mast cells are present in patients with mild allergic asthma or even in non-asthmatic allergic rhinitis patients (AR) who have developed bronchial hyperactivity (BHR).

METHODS

Bronchial and alveolar tissues were obtained from healthy controls, AR patients with or without BHR, and AR patients with concurrent asthma. Samples were processed for immunohistochemical identification of MC(T) and MC(TC) and expression of FcεRI and surface-bound IgE.

RESULTS

Bronchial mast cell expression of FcεRI was high in all groups. In contrast, in the alveolar tissue, the expression of FcεRI on mast cells was low in healthy controls and in the AR patient groups, whereas a high expression was present in AR patients with concurrent asthma (P = 0.006 compared to controls). The asthmatics had a 29-fold increase in numbers (P = 0.006) and a 19-fold increase in proportion (P = 0.007) of alveolar mast cells that expressed surface-bound IgE.

CONCLUSIONS

The present data show that alveolar mast cells in patients with mild atopic asthma, but not atopic patients with AR, have turned into a highly FcεRI- and IgE-expressing phenotype. These data support the hypothesis that increased FcεRI expression on alveolar mast cells is a novel disease-specific feature of allergic asthma that is important for understanding asthma phenotypes and designing new therapeutic strategies.

The association between fractional exhaled nitric oxide (FeNO) and cat dander in asthmatic children

BACKGROUND

The aim of our study was to assess risk factors of increased FeNO in asthmatic children with no cat at home.

METHODS

It was a retrospective, cross-sectional study. We evaluated data from medical documentation of children with asthma: FeNO results, allergen sensitization, seasonal allergen exposure, FEV(1), allergic rhinitis (AR) diagnosis and cat presence at home. We assessed asthma severity using mean doses of inhaled glucocorticosteroids and a management approach based on control according to the newest guidelines of Global Initiative for Asthma (GINA) throughout the last three months before the measurement of FeNO and spirometry.

RESULTS

316 patients (age 6-18) completed the study. Sensitization to cat dander was associated with the highest median value of FeNO concentration compared to other allergens in our patients (28,4ppb) and co-existing sensitization did not affect FeNO level. Median levels of FeNO increased linearly with patient's age. In asthmatics with AR, the levels of FeNO were increased significantly compared to asthmatics without AR (20.8 vs. 16.3, respectively). We showed that in patients without AR, sensitization to cat allergen was associated with more severe asthma in comparison to other perennial allergy (step 4 vs. other steps according to GINA treatment steps). The above relation was not observed in patients with AR. We did not observe correlation between allergy profile and FEV(1) among patients in neither subgroup nor in general population.

CONCLUSIONS

We revealed that sensitization to cat dander was associated with the highest increase of FeNO concentration compared to other allergens in patients not having any cat at home ever. We also observed that in patients without allergic rhinitis, sensitization to cat allergen, compared to other perennial allergy, was associated with more severe asthma.

The role of inhaled and/or nasal corticosteroids on the bronchodilator response

PURPOSE

To compare the profiles of the bronchodilator response (BDR) among children with asthma and/or allergic rhinitis (AR) and to determine whether BDR in these children is reduced by treatment with inhaled and/or nasal corticosteroid.

METHODS

Sixty-eight children with asthma (mean age, 10.9 years), 45 children with comorbid asthma and AR (mean age, 10.5 years), and 44 children with AR alone (mean age, 10.2 years) were investigated. After a 2-week baseline period, all children were treated with inhaled fluticasone propionate (either 100 or 250 µg b.i.d., tailored to asthma severity) or nasal fluticasone propionate (one spray b.i.d. in each nostril) or both, according to the condition. Before and 2 weeks after starting treatment, all children were evaluated with spirometry and bronchodilator testing. BDR was calculated as a percent change from the forced expiratory volume in 1 second (FEV(1)) at baseline.

RESULTS

The mean BDR was 10.3% [95% confidence interval (CI) 8.3-12.4%] in children with asthma, 9.0% (95% CI 7.3-10.9%) in subjects with asthma and AR, and 5.0% (95% CI 4.1-5.9%) in children with AR alone (P<0.001). After treatment, the mean BDR was reduced to 5.2% (95% CI 4.2-6.3%) (P<0.001) in children with asthma and to 4.5% (95% CI 3.5-5.5%) (P<0.001) in children with asthma and AR. However, children with rhinitis showed no significant change in BDR after treatment, with the mean value being 4.7% (95% CI 3.7-5.8%) (P=0.597).

CONCLUSION

The findings of this study imply that an elevated BDR in children with AR cannot be attributed to nasal inflammation alone and highlights the close relationship between the upper and lower airways.

Alveolar macrophages reduce airway hyperresponsiveness and modulate cytokine levels

The authors have recently demonstrated that alveolar macrophages (AMs) are important in protecting against early phase reactions and airway hyperresponsiveness following allergen challenge. To further understand the mechanisms involved, the authors investigated the capacity of AMs to modulate airway inflammation and cytokine levels in bronchoalveolar lavage (BAL). AMs from allergy-susceptible Brown Norway (BN) rats or allergy-resistant Sprague-Dawley (SD) rats were transferred into AM-depleted BN rats 24 hours prior to allergen challenge. Methacholine-induced airway hyperresponsiveness was examined 24 hours following ovalbumin challenge. Total cells, cell types, and cytokine levels (tumor necrosis factor [TNF], interleukin [IL]-4, IL-10, IL-12 and IL-13) in BAL were measured 24 hours after allergen challenge. The transfer of AMs from SD rats into AM-depleted BN rats 24 hours before allergen challenge eliminated methacholine-induced airway hyperresponsiveness, but did not modify the number and the type of inflammatory cells in BAL. Levels of IL-13 and TNF were significantly higher in BAL of BN rats compared with SD rats. Interestingly, IL-13 and TNF levels were significantly increased and inhibited, respectively, in BN rats that received AMs from SD rats compared with BN rats. Our data suggest that AM modulation of cytokine milieu is involved in the reduction of airway hyperresponsiveness.

The link between allergic rhinitis and asthma: the united airways disease

Rhinitis and asthma are often associated and the two disorders interact at various levels. Rhinitis typically precedes the development of asthma and can contribute to unsatisfactory asthma control. The presence and type of asthma is influenced by sensitization, and the duration and severity of allergic rhinitis. Nasal symptoms, airflow and markers of inflammation directly correlate with lower airway involvement. Local tissue factors, such as microbial stimuli and systemic inflammatory mechanisms, play a role in the clinical expression of the allergic airway syndrome. There is increasing evidence that suggests a major involvement of airway epithelial cells in the pathogenesis of both asthma and allergic rhinitis. Even in patients with rhinitis who do not have asthma, subclinical changes in the lower airways and inflammatory mediators can be detected. The pathogenic role of paranasal sinus infections in respiratory allergy has been better elucidated but there remains a need for further research. Treatment of established rhinitis may affect asthma control and could have some impact on airway obstruction, but a direct effect of rhinitis therapy on lower airway inflammation remains to be clearly established.

Emerging roles of T helper subsets in the pathogenesis of asthma

The cardinal features of asthma include pulmonary inflammation and airway hyperresponsiveness (AHR). Classically, asthma, specifically allergic asthma, has been attributed to a hyperactive Th2 cell immune response. However, the Th2 cell-mediated inflammation model has failed to adequately explain many of the clinical and molecular aspects of asthma. In addition, the outcomes of Th2-targeted therapeutic trials have been disappointing. Thus, asthma is now believed to be a complex and heterogeneous disorder, with several molecular mechanisms underlying the airway inflammation and AHR that is associated with asthma. The original classification of Th1 and Th2 pathways has recently been expanded to include additional effector Th cell subsets. These include Th17, Th9 and Treg cells. Emerging data highlight the involvement of these new Th cell subsets in the initiation and augmentation of airway inflammation and asthmatic responses. We now review the roles of these recently classified effector Th cell subsets in asthmatic inflammation and the insights they may provide in addition to the traditional Th2 paradigm. The hope is that a clearer understanding of the inflammatory pathways involved and the mediators of inflammation will yield better targeted therapeutics.

Associations of airway inflammation and responsiveness markers in non asthmatic subjects at start of apprenticeship

Background

Bronchial Hyperresponsiveness (BHR) is considered a hallmark of asthma. Other methods are helpful in epidemiological respiratory health studies including Fractional Exhaled Nitric Oxide (FENO) and Eosinophils Percentage (EP) in nasal lavage fluid measuring markers for airway inflammation along with the Forced Oscillatory Technique measuring Airway resistance (AR). Can their outcomes discriminate profiles of respiratory health in healthy subjects starting apprenticeship in occupations with a risk of asthma?

Methods

Rhinoconjunctivitis, asthma-like symptoms, FEV1 and AR post-Methacholine Bronchial Challenge (MBC) test results, FENO measurements and EP were all investigated in apprentice bakers, pastry-makers and hairdressers not suffering from asthma. Multiple Correspondence Analysis (MCA) was simultaneously conducted in relation to these groups and this generated a synthetic partition (EI). Associations between groups of subjects based on BHR and EI respectively, as well as risk factors, symptoms and investigations were also assessed.

Results

Among the 441 apprentice subjects, 45 (10%) declared rhinoconjunctivitis-like symptoms, 18 (4%) declared asthma-like symptoms and 26 (6%) suffered from BHR. The mean increase in AR post-MBC test was 21% (sd = 20.8%). The median of FENO values was 12.6 ppb (2.6-132 range). Twenty-six subjects (6.7%) had EP exceeding 14%. BHR was associated with atopy (p < 0.01) and highest FENO values (p = 0.09). EI identified 39 subjects with eosinophilic inflammation (highest values of FENO and eosinophils), which was associated with BHR and atopy.

Conclusions

Are any of the identified markers predictive of increased inflammatory responsiveness or of development of symptoms caused by occupational exposures? Analysis of population follow-up will attempt to answer this question.

Relationship between fractional exhaled nitric oxide and nasal nitric oxide in airways disease

BACKGROUND

Invasive techniques show evidence of a unified allergic airway. Nitric oxide is measured noninvasively from the lungs (fractional exhaled nitric oxide [FeNO]) and nose (nasal nitric oxide [nNO]).

OBJECTIVE

To investigate the relationship between FeNO and nNO in different airway conditions.

METHODS

A total of 227 participants were assessed: 41 healthy volunteers (HVs), 33 patients with asthma, 52 patients with allergic rhinitis (AR), 63 with unified airway disease (UAD), and 38 with nasal polyposis (NP). Correlation and multiple linear regression analyses were performed.

RESULTS

Geometric means (95% confidence intervals) for FeNO were as follows: 14.7 (12.4-17.5) ppb for HVs, 29.0 (22.5-37.4) ppb for asthma patients, 23.1 (19.0-28.1) for AR patients, 27.2 (23.0-32.4) for UAD patients, and 28.5 (21.5-37.8) for NP patients. For nNO, the values were as follows: 878.1 (807.0-955.6) ppb for HVs, 674.1 (557.4-815.1) for asthma patients, 853.3 (778.8-934.8) ppb for AR patients, 763.4 (694.1-839.5) for UAD patients, and 388.6 (317.9-474.9) for NP patients. The nNO was lower in the NP group than the other groups (P < .001). The nNO and FeNO were correlated in the AR patients (r = 0.56; P < .0001) and HVs (r = 0.44; P = .004) but not significantly in the other groups. Multiple linear regression of the whole cohort demonstrated that after diagnosis, age, sex, and inhaled corticosteroids were taken into account nNO had a significant association with FeNO (P = .02).

CONCLUSION

Reduced nNO in NP patients is due to ostiomeatal complex obstruction. FeNO is sensitive to suppression by inhaled corticosteroids. The AR and HV groups have no such confounders; hence, correlation is most evident. Exclusion of confounders reveals a correlation between upper and lower airway inflammation with noninvasive techniques.

CysLT1-R expression following allergen provocation in asthma and allergic rhinitis

Cysteinyl leukotrienes (CysLTs) contribute to allergic and inflammatory diseases through CysLT(1)-R. We aimed to assess CysLT(1)-R mRNA expression in induced sputum of rhinitics with or without asthma before and following allergen challenges. Both groups underwent nasal and "low dose" lung allergen challenges. Asthmatics also underwent "standard" lung challenge. Sputum was obtained before and at different time-points following the challenges for CysLT(1)-R, 5-lipoxygenase (5-LO), and eotaxin mRNA assessments. At baseline, there was no difference in mediator levels between groups. An increase in CysLT(1)-R mRNA (p=0.04) and a trend towards an increase in 5-LO and eotaxin (p=0.06 for both) at 24 h post-nasal challenge were observed. Following "low dose" lung allergen challenge, there was a trend towards an increase in CysLT(1)-R (p=0.07). In conclusion, CysLT(1)-R gene expression changes can be detected in sputum following allergen challenges. No difference was observed between groups, suggesting that changes in CysLT(1)-R expression occur whether or not the subject has concurrent asthma.

Eosinophil progenitors in airway diseases: clinical implications

Asthma, allergic rhinitis, nasal polyposis, chronic rhinosinusitis, and related forms of upper and lower airway diseases are often characterized by eosinophilic and basophilic inflammation, involving systemic processes. Eosinophil/basophil (Eo/B) lineage-committed progenitor cells in cord blood, peripheral blood, bone marrow, lung tissue, and sputum are up-regulated in the above conditions, and respond to allergen and other stimuli with increased differentiative and migratory capacity. A considerable body of evidence now exists showing that activation of such Eo/B-selective hemopoietic processes is not only associated with the onset and maintenance of allergic inflammation in atopic adults, but also with the development of the allergic diathesis. Moreover, eosinophilopoietic processes within hemopoietic compartments and, importantly, at mucosal tissue sites during an allergic inflammatory response provide novel targets for the treatment of allergy as a systemic process and disease.

Lower airway disease in asthmatics with and without rhinitis

STUDY OBJECTIVES

The purpose of this study was to determine if asthma with rhinitis and asthma without rhinitis represent distinct forms of disease.

DESIGN

We performed a prospective cross-sectional study.

PARTICIPANTS

The study included healthy controls, participants with asthma without rhinitis, and participants with both asthma and rhinitis. Interventions We compared lung function and airway inflammation between the three groups of participants.

RESULTS

We recruited 32 participants: 12 normals, 8 asthmatics without rhinitis, and 12 with rhinitis. Compared to asthmatics with rhinitis, asthmatics without rhinitis had more severe airflow limitation (FEV(1)/FVC = 60.6% [IQR = 22.8] vs. 74.8% [IQR = 7.8] and fewer induced sputum eosinophils (2.8 [IQR = 5.8] and 9.6 [IQR = 23.8], respectively). Sputum interleukin-6 correlated inversely with lung function measured by postbronchodilator FEV(1) in the study cohort (Spearman correlation coefficient = -0.55, p < 0.01).

CONCLUSIONS

Asthmatics without rhinitis tend to have lower lung function and less eosinophilic inflammation in the lung. This small study suggests that asthmatics without rhinitis represent a distinct phenotype of asthma in which low lung function is dissociated from eosinophilic cellular inflammation, and it suggests that larger studies addressing this phenotype are warrented.

Indices of lower airway inflammation in children monosensitized to house dust mite after nasal allergen challenge

BACKGROUND

There are few available data assessing the united airway disease and its systemic aspects in children. With this study, we aimed to investigate the inflammation markers of upper and lower airways before and after nasal allergen challenge in mite sensitive children with different clinical expression of the allergic disease.

METHODS

Four study groups were formed: rhinitis only, without bronchial hyper-responsiveness (R, n = 10), rhinitis with asthma (R + A, n = 22), atopic asymptomatics (AA, n = 8) and nonallergic healthy controls (C, n = 10). Blood eosinophils, nasal and sputum eosinophils, sputum eosinophil cationic protein (ECP) and cys-LTs, and serum ECP levels were measured before and 24 h after nasal allergen challenge.

RESULTS

The groups were comparable in terms of age and gender. Cumulative symptom scores recorded during and 1 h after nasal challenge were not significantly different between patients with R, R + A and AA groups. At T(24), the children belonging to R, R + A and AA showed significant increases in nasal eosinophils (P < 0.01, P < 0.001, and P = 0.01, respectively), sputum eosinophils (P = 0.01, P < 0.001, and P < 0.05, respectively) and blood eosinophils (P < 0.01, P < 0.001, and P < 0.05, respectively). Similarly, increases in sputum ECP (P < 0.01, P < 0.001, and P = 0.07, respectively) and sputum cys-LT levels (P = 0.07, P < 0.001, and P < 0.05, respectively) were detected in children belonging to these three groups at T(24). Sputum eosinophils significantly correlated with blood eosinophils (r = 0.54, P < 0.001) and sputum ECP (r = 0.58, P < 0.001) at T(24).

CONCLUSIONS

This study showed that nasal allergen challenge increased markers of eosinophilic inflammation in both upper and lower airways of children monosensitized to mites, even before the onset of clinical symptoms.

Endotyping asthma: new insights into key pathogenic mechanisms in a complex, heterogeneous disease

Clinical asthma is very widely assumed to be the net result of excessive inflammation driven by aberrant T-helper-2 (Th2) immunity that leads to inflamed, remodelled airways and then functional derangement that, in turn, causes symptoms. This notion of disease is actually poorly supported by data, and there are substantial discrepancies and very poor correlation between inflammation, damage, functional impairment, and degree of symptoms. Furthermore, this problem is compounded by the poor understanding of the heterogeneity of clinical disease. Failure to recognise and discover the underlying mechanisms of these major variants or endotypes of asthma is, arguably, the major intellectual limitation to progress at present. Fortunately, both clinical research and animal models are very well suited to dissecting the cellular and molecular basis of disease endotypes. This approach is already suggesting entirely novel pathways to disease-eg, alternative macrophage specification, steroid refractory innate immunity, the interleukin-17-regulatory T-cell axis, epidermal growth factor receptor co-amplification, and Th2-mimicking but non-T-cell, interleukins 18 and 33 dependent processes that can offer unexpected therapeutic opportunities for specific patient endotypes.

Magnitude of late asthmatic response to allergen in relation to baseline and allergen-induced sputum eosinophilia in mild asthmatic patients

BACKGROUND

Late asthmatic response (LAR) to allergen challenge is a validated method for studying the pathogenesis of and new treatments for asthma in the laboratory.

OBJECTIVE

To evaluate the relationship between the magnitude of allergen-induced LAR and clinical and biological determinants, including sputum and blood eosinophil percentages and eosinophil cationic protein concentrations.

METHODS

Thirty-eight untreated mild asthmatic patients (mean age, 21.2 years) were selected for the presence of allergen-induced early asthmatic response (EAR) and LAR. Each patient measured methacholine responsiveness (provocation dose that caused a decrease in forced expiratory volume in 1 second of 20% [PD20FEV1]) at baseline, differential blood cell counts and eosinophil cationic protein levels in blood and induced sputum, and serum neutrophil chemotactic activity at baseline and 24 hours after allergen challenge.

RESULTS

A correlation was found between LAR (as area under the curve [AUC]) and sputum eosinophil percentages at baseline (r = 0.51; P = .001) and 24 hours after allergen challenge (r = 0.44; P < .007). Furthermore, we found significant correlations between AUC LAR and AUC EAR, baseline methacholine PD20FEV1, baseline blood eosinophil percentages, and baseline serum neutrophil chemotactic activity. A stepwise multiple regression analysis showed that the stronger determinants of AUC LAR were baseline sputum eosinophilia and AUC EAR.

CONCLUSION

Baseline sputum eosinophilia and functional findings are determinants of the magnitude of allergen-induced LAR.

Allergic rhinitis with hyper-responsiveness differ from asthma in degree of peripheral obstruction during metacholine challenge test

Allergic rhinitis (AR) is a risk factor for developing clinical asthma. Moreover, AR is often associated with bronchial hyper-responsiveness (BHR). The aim of this study was to compare the degree of involvement of the peripheral airways during metacholine (MCh) challenge test in asthmatics and patients with AR with or without BHR by using the impulse oscillometry (IOS) technique. Fifty-three patients with seasonal AR were investigated with MCh challenge test and IOS. Thirteen healthy non-reactive subjects served as controls. MCh challenge test was performed, cut-off value FEV1PD20 2000 microg. Linear regression analysis was used to calculate a MCh/FEV1 slope (Slope-FEV1MCh), which was used as an index of BHR. IOS was performed, measuring respiratory resistance and reactance during the MCh challenge test. Twenty-six subjects had both AR and asthma symptoms, 27 patients reported AR only, without asthma symptoms, 17 (63%) manifested BHR by spirometric criteria. Patients with AR and symptoms of asthma manifested greater peripheral airway obstruction compared to those with AR only with BHR. Increased peripheral obstruction in the asthmatic group compared to patients with AR and BHR may explain previous findings that asthmatics perceive greater airway obstruction during MCh challenge tests.

Systemic and local eosinophil inflammation during the birch pollen season in allergic patients with predominant rhinitis or asthma

Background

The aim of the study was to investigate inflammation during the birch pollen season in patients with rhinitis or asthma.

Methods

Subjects with birch pollen asthma (n = 7) or rhinitis (n = 9) and controls (n = 5) were studied before and during pollen seasons. Eosinophils (Eos), eosinophil cationic protein (ECP) and human neutrophil lipocalin were analysed.

Results

Allergic asthmatics had a larger decline in FEV1 after inhaling hypertonic saline than patients with rhinitis (median) (-7.0 vs.-0.4%, p = 0.02). The asthmatics had a lower sesonal PEFR than the rhinitis group. The seasonal increase in B-Eos was higher among patients with asthma (+0.17 × 109/L) and rhinitis (+0.27 × 109/L) than among controls (+0.01 × 109/L, p = 0.01). Allergic asthmatics and patients with rhinitis had a larger increase in sputum ECP (+2180 and +310 μg/L) than the controls (-146 μg/L, p = 0.02). No significant differences in inflammatory parameters were found between the two groups of allergic patients.

Conclusion

Patients with allergic asthma and rhinitis have the same degree of eosinophil inflammation. Despite this, only the asthmatic group experienced an impairment in lung function during the pollen season.

Cysteinyl-leukotriene levels in sputum differentiate asthma from rhinitis patients with or without bronchial hyperresponsiveness

BACKGROUND

We have previously reported that asthma differs from rhinitis with or without bronchial hyperresponsiveness in the perception and degree of lower airway inflammation.

OBJECTIVE

The aim of the present study was to investigate whether sputum levels of inflammatory markers could further distinguish these patient groups.

METHODS

Patients with seasonal allergic rhinitis with or without asthma or bronchial hyperresponsiveness to methacholine were investigated. Induced sputum was performed during as well as off season, and analysed for cysteinyl-leukotrienes, hyaluronan, eosinophilic cationic protein (ECP) and other inflammatory markers.

RESULTS

Asthmatic patients differentiated from those with rhinitis with or without bronchial hyperresponsiveness in levels of cysteinyl-leukotrienes [geometric mean: 3.3 (lower 95%-upper 95% confidence interval (CI) of geometric mean: 1.9-5.1) vs. 1.4 (0.9-2.2) and 0.7 (0.3-1.6) pg/microg total protein] and hyaluronan [0.30 (0.22-0.43) vs. 0.15 (0.10-0.20) and 0.20 (0.12-0.35) ng/microg total protein] in sputum. The levels of cysteinyl-leukotrienes decreased in sputum from the asthmatic patients, while the levels of hyaluronan remained elevated off-season. Furthermore, elevated levels of ECP were noticed among both the asthmatic and rhinitis patients with hyperresponsiveness compared with controls [0.022 (0.014-0.033) and 0.015 (0.011-0.021) compared with 0.010 (0.007-0.014) ng/microg total protein]. The level of ECP remained elevated off season.

CONCLUSION

Cysteinyl-leukotrienes are possibly more related to mast cell-mediated inflammation and remodelling, also indicated by increased levels of hyaluronan during and off season. This inflammation may be partly different from the eosinophil-driven inflammation.

Bronchial responsiveness to methacholine and adenosine 5'-monophosphate in young children with asthma: their relationship with blood eosinophils and serum eosinophil cationic protein

BACKGROUND

Bronchial hyperresponsiveness is a characteristic feature of asthma, and is usually measured by bronchial challenges using direct or indirect stimuli. Blood eosinophil numbers and serum levels of eosinophil cationic protein (ECP) are considered as indirect measures of airway inflammation in asthma. The aim of this study was to investigate whether bronchial responsiveness to adenosine 5'-monophosphate (AMP) is more closely associated with blood eosinophil markers, compared with that to methacholine, in young children with asthma.

METHODS

Methacholine and AMP bronchial challenges were performed in 4- to 6-year-old children with asthma (n = 77) and in healthy controls (n = 32), using a modified auscultation method. The end-point was defined as the appearance of wheezing and/or oxygen desaturation. The peripheral blood eosinophil counts and serum ECP concentrations were determined in each subject.

RESULTS

A positive response to methacholine (end-point concentration < or =8mg/ml) and to AMP (end-point concentration < or =200 mg/ml) was observed in 74 (96.1%) and 66 asthmatic children (85.7%), respectively. A majority of controls was unresponsive to both challenges. In the asthma group, there was no significant correlation between methacholine end-point concentration and the eosinophil counts (r = -0.111, P = 0.337) or serum ECP levels (r = -0.126, P = 0.274). In contrast, AMP end-point concentration correlated significantly with the eosinophil counts (r = -0.372, P = 0.001) and with serum ECP levels (r = -0.371, P = 0.001).

CONCLUSIONS

Our results suggest that bronchial responsiveness to AMP is more closely related to airway inflammation, compared with that to methacholine, and support the potential usefulness of AMP challenges in detecting inflammatory changes in young children with asthma.

Comparison of deltaFVC between patients with allergic rhinitis with airway hypersensitivity and patients with mild asthma

BACKGROUND

In asthmatic individuals, airway sensitivity and maximal airway response are increased. Airway sensitivity is usually evaluated by measuring the provocation concentration of inhaled methacholine or histamine that causes a decrease in forced expiratory volume in 1 second of 20% (PC20). The percentage decrease in forced vital capacity at the PC20 (deltaFVC) has been proposed as a surrogate marker for maximal airway response. Individuals with allergic rhinitis and no clinical evidence of asthma frequently exhibit airway hypersensitivity.

OBJECTIVE

To compare the deltaFVC between patients with allergic rhinitis and mild asthmatic patients with a similar degree of airway hypersensitivity.

METHODS

A retrospective analysis of methacholine challenge test data from 72 children with allergic rhinitis and airway hypersensitivity (methacholine PC20 < 16 mg/mL) (rhinitis group) and from 72 children with mild atopic asthma matched to the rhinitis group regarding the methacholine PC20 (asthma group). The deltaFVC was calculated on the concentration-response curve to methacholine.

RESULTS

The mean +/- SD deltaFVC was significantly lower in the rhinitis group (15.0% +/- 3.6%) vs the asthma group (17.4% +/- 5.3%) (P = .002). There was no significant correlation between the deltaFVC and PC20 in the rhinitis (r = -0.101; P = .41) and asthma (r = -0.023; P = .85) groups when 2 patients with PC20 less than 1 mg/mL were excluded from each group.

CONCLUSIONS

Patients with allergic rhinitis and airway hypersensitivity had a significantly lower deltaFVC than methacholine PC20-matched mild asthmatic patients, suggesting that the level of maximal airway response in patients with allergic rhinitis is lower than that in mild asthmatic patients with a similar degree of airway hypersensitivity.

Intercellular adhesion molecule 1 and tumor necrosis factor alpha in asthma and persistent allergic rhinitis: relationship with disease severity

BACKGROUND

Tumor necrosis factor alpha (TNF-alpha) is involved in the up-regulation of intercellular adhesion molecule 1 (ICAM-1). Allergic rhinitis is often associated with bronchial hyperresponsiveness.

OBJECTIVE

We investigated the relationship between allergic airway disease severity and serum concentrations of soluble ICAM-1 (sICAM-1) and TNF-alpha and nasal expression of ICAM-1.

METHODS

Serum concentrations of TNF-alpha and sICAM-1 were investigated in 85 adults with persistent rhinitis and 90 patients with asthma. Seventy patients with rhinitis were challenged with methacholine. Nasal biopsy for ICAM-1 expression was performed in 6 patients with moderate-severe rhinitis and in 6 patients with mild rhinitis.

RESULTS

In patients with rhinitis, serum sICAM-1 concentrations were as follows: group without bronchial hyperresponsiveness (n = 29), 206.85 ng/mL; group with bronchial hyperresponsiveness but without asthma symptoms (n = 20), 233.39 ng/mL; and group with newly recognized asthma (n = 21), 260.06 ng/mL. The sICAM-1 level was significantly lower in patients with mild rhinitis (216.21 ng/mL) than in patients with moderate-severe rhinitis (244.08 ng/mL). Nasal ICAM-1 expression was significantly higher in the moderate-severe rhinitis group than in the mild rhinitis group. In patients with asthma, serum concentrations of sICAM-1 were as follows: patients with mild asthma, 272.8 ng/mL; patients with moderate asthma, 340.16 ng/mL; patients with severe asthma without oral corticosteroids therapy, 426.74 ng/mL; and patients with severe asthma with oral corticosteroids therapy, 314 ng/mL. The serum TNF-alphaa concentration differed between patients with rhinitis (n = 15) (1.065 pg/mL) and patients with asthma (n = 12) (3.46 pg/mL). Among patients with asthma, TNF-alpha concentrations were similar in all groups classified according to the disease severity.

CONCLUSIONS

sICAM and ICAM-1 expression correlates with airways diseases severity.

Eosinophilic inflammation, remodeling of lower airway, bronchial responsiveness and cough reflex sensitivity in non-asthmatic subjects with nasal allergy

BACKGROUND

It has been reported that nasal allergy influences the lower airway inflammation and functions. We elucidated whether nasal allergy would contribute to lower airway inflammation and functions.

METHODS

266 subjects aged 21-39 years were interviewed with special emphasis on history of asthma and nasal allergies (perennial allergic rhinitis (PAR) and seasonal allergic rhinitis (Japanese cedar pollinosis; PO)). Symptomatic subject was defined when nasal symptoms were present during a 3-week study period. Pulmonary function, provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 s (PC20), capsaicin cough threshold defined as capsaicin concentration eliciting 5 or more coughs (C5) and eosinophil percentage in hypertonic saline-induced sputum were measured.

RESULTS

Based on the interview, 232 subjects without asthma were divided into symptomatic (n = 25) and asymptomatic (n = 22) PAR, PO on-season (n = 15) and off-season (n = 36), and non-nasal allergy subjects (control) (n = 134). Sputum eosinophils were significantly greater in symptomatic PAR than another four groups (p < 0.01). FEV1/FVC ratio was significantly lower in PAR than control (p < 0.05). Maximum mean expiratory flow was lower in PAR than control (asymptomatic: p < 0.05, symptomatic: p = 0.06). C5 was not different among groups. PAR tended to have a lower PC20 compared to control (symptomatic: p = 0.078; asymptomatic: p = 0.086).

CONCLUSIONS

These results suggest that eosinophilic inflammation occurred in symptomatic period of PAR may contribute to development of lower airway remodeling and bronchial hyperresponsiveness. Reversely, PO may not be associated with lower airway eosinophilic inflammation or abnormal bronchial functions. Nasal allergy dose not influence the cough reflex sensitivity.

Allergic rhinitis with or without concomitant asthma: difference in perception of dyspnoea and levels of fractional exhaled nitric oxide

BACKGROUND/AIM

Allergic rhinitis (AR) is a risk factor for developing clinical asthma. Moreover, AR is often associated with bronchial hyper-responsiveness (BHR). The aim of the present study was to investigate whether patients with AR and asthma differed from AR with or without BHR in degree of perception of dyspnoea and airway inflammation, measured as fractionated exhaled nitric oxide (NO).

MATERIALS

Twenty-nine patients with seasonal AR (timothy) were investigated with metacholine challenge test. Fourteen healthy non-reactive subjects served as controls.

METHODS

(1) Metacholine challenge test, cut-off value forced expiratory volume in 1 s (FEV(1)) PD20 2,000 microg. Slope value for metacholine was calculated as %fall in FEV(1)/mol metacholine. Dyspnoea during challenge was measured with a 10-graded modified Borg score. (2) Measurement of fractional-exhaled nitric oxide (FENO) at flow rate 50 mL/s.

RESULTS

Eighteen patients reported AR only, without asthma symptoms, and 12 (67%) were BHR. Eleven subjects had both rhinitis and asthma symptoms. Patients with rhinitis and asthma reported significantly more dyspnoea per percent fall in FEV(1) compared with those with rhinitis and BHR. Moreover, those with rhinitis and asthma had significantly higher NO values compared with those with rhinitis and BHR.

CONCLUSION

The difference between rhinitis patients with or without asthma symptoms seems to be mainly a question of perception of dyspnoea. However, FENO measurement indicates that dyspnoea may also be associated with increased inflammatory activity in the peripheral airways.