Specific IgE response to trichophyton and asthma severity

Fungal Sensitization and Human Allergic Disease

PURPOSE OF THE REVIEW

Fungal sensitizations have been associated with hypersensitivity reactions with variable levels of evidence available to link types of fungi with human disease. We conducted systematic reviews of the literature to identify the strength of evidence linking lesser-studied fungi for which there are commercially available extracts to identify populations in which they were useful in clinical practice.

RECENT FINDINGS

Excluding five fungi for which hundreds of articles were identified, there are 54 articles on the remaining fungi with clinical data. For 12 of the fungi, the prevalence of fungal sensitization varies in different hypersensitivity disorders due to factors related to geographic areas, age, and other underlying medical conditions. There were no studies linking seven genera to human disease. Most of the commercially available fungal extracts are uncommonly associated with hypersensitivity reactions in humans. Specific extracts may be useful in particular disease states such as allergic fungal sinusitis or allergic bronchopulmonary mycosis, or when routine testing fails to identify a cause of uncontrolled disease, such as in asthma.

Poorly controlled asthma - Easy wins and future prospects for addressing fungal allergy

Poorly controlled asthma is especially common in low resource countries. Aside from lack of access to, or poor technique with, inhaled beta-2 agonists and corticosteroids, the most problematic forms of asthma are frequently associated with both fungal allergy and exposure, especially in adults leading to more asthma exacerbations and worse asthma. The umbrella term 'fungal asthma' describes many disorders linked to fungal exposure and/or allergy to fungi. One fungal asthma endotype, ABPA, is usually marked by a very high IgE and its differential diagnosis is reviewed. Both ABPA and fungal bronchitis in bronchiectasis are marked by thick excess airway mucus production. Dermatophyte skin infection can worsen asthma and eradication of the skin infection improves asthma. Exposure to fungi in the workplace, home and schools, often in damp or water-damaged buildings worsens asthma, and remediation improves symptom control and reduces exacerbations. Antifungal therapy is beneficial for fungal asthma as demonstrated in nine of 13 randomised controlled studies, reducing symptoms, corticosteroid need and exacerbations while improving lung function. Other useful therapies include azithromycin and some biologics approved for the treatment of severe asthma. If all individuals with poorly controlled and severe asthma could be 'relieved' of their fungal allergy and infection through antifungal therapy without systemic corticosteroids, the health benefits would be enormous and relatively inexpensive, improving the long term health of over 20 million adults and many children. Antifungal therapy carries some toxicity, drug interactions and triazole resistance risks, and data are incomplete. Here we summarise what is known and what remains uncertain about this complex topic.

Sensitization pattern to environmental allergens in a Japanese population

Background

We previously described the prevalence of allergen-specific IgE in a general population of Japanese adults.

Objective

We sought to elucidate allergen sensitization patterns in this population.

Methods

Serum samples had been obtained from 800 blood donors aged 20 to 59 years and living in Tokyo, Japan, in 2005 and stored in the Japanese Red Cross Society. These samples were examined for IgE levels, total and specific for 23 allergens or allergen sources correlated with allergic airway diseases using the ImmunoCAP method. Exploratory and confirmatory factor analyses were performed to uncover the relationship among allergen-specific IgE based on their titers. Hierarchical cluster analysis was executed using Ward's method based on standardized factor scores identified through factor analysis.

Results

Exploratory factor analysis revealed 6 categories of allergen-specific IgE: specific to 2 types of animals (insects and Dermatophagoides pteronyssinus/animal dander), 2 types of pollens (group 1 [Japanese cedar and cypress] and group 2 [alder, grass, and weeds]), and 2 types of microorganisms (fungi and commensal microorganisms on the skin). The Japanese population was categorized into 3 clusters: (A) nonatopic type, (B) house dust mite-dominant sensitization type, and (C) panatopic type. The panatopic group could be further classified into 2 subclusters positive and negative for fungal sensitization.

Conclusions

This study demonstrated that a Japanese population could be divided into 3 clusters according to the sensitization pattern to 6 types of allergens.

Environment and Host-Genetic Determinants in Early Development of Allergic Asthma: Contribution of Fungi

Asthma is a chronic debilitating airway disease affecting millions of people worldwide. Although largely thought to be a disease of the first world, it is now clear that it is on the rise in many middle- and lower-income countries. The disease is complex, and its etiology is poorly understood, which explains failure of most treatment strategies. We know that in children, asthma is closely linked to poor lung function in the first 3-years of life, when the lung is still undergoing post-natal alveolarization phase. Epidemiological studies also suggest that environmental factors around that age do play a critical part in the establishment of early wheezing which persists until adulthood. Some of the factors that contribute to early development of asthma in children in Western world are clear, however, in low- to middle-income countries this is likely to differ significantly. The contribution of fungal species in the development of allergic diseases is known in adults and in experimental models. However, it is unclear whether early exposure during perinatal or post-natal lung development influences a protective or promotes allergic asthma. Host immune cells and responses will play a crucial part in early development of allergic asthma. How immune cells and their receptors may recognize fungi and promote allergic asthma or protect by tolerance among other immune mechanisms is not fully understood in this early lung development stage. The aim of this review is to discuss what fungal species are present during early exposure as well as their contribution to the development of allergic responses. We also discuss how the host has evolved to promote tolerance to limit hyper-responsiveness to innocuous fungi, and how host evasion by fungi during early development consequentially results in allergic diseases.

Update in Pediatric Asthma: Selected Issues

Asthma is a complex condition that affects 14% of the world's children and the approach to management includes both pharmacologic as well as non-pharmacologic strategies including attention to complex socioeconomic status phenomena. After an historical consideration of asthma, allergic and immunologic aspects of asthma in children and adolescents are presented. Concepts of socioeconomic aspects of asthma are considered along with environmental features and complications of asthma disparities. Also reviewed are links of asthma with mental health disorders, sleep disturbances and other comorbidities. A stepwise approach to asthma management is discussed that includes pharmacologic and non-pharmacologic strategies in the pediatric population. The role of immunotherapy and use of various immunomodulators are considered as well.

Recent Findings in Onychomycosis and Their Application for Appropriate Treatment

Onychomycosis is mainly caused by two dermatophyte species, Trichophyton rubrum and Trichophyton interdigitale. A study of nail invasion mechanisms revealed that the secreted subtilisin Sub6, which has never been detected under in vitro growth conditions, was the main protease secreted by T. rubrum and T. interdigitale during infection. In contrast, most of the proteases secreted during the digestion of keratin in vitro were not detected in infected nails. The hypothesis that proteases isolated from dermatophytes grown in a keratin medium are virulence factors is no longer supported. Non-dermatophyte fungi can also be infectious agents in nails. It is necessary to identify the infectious fungus in onychomycosis to prescribe adequate treatment, as moulds such as Fusarium spp. and Aspergillus spp. are insensitive to standard treatments with terbinafine or itraconazole, which are usually applied for dermatophytes. In these refractory cases, topical amphotericin B treatment has shown to be effective. Terbinafine treatment failure against dermatophytes is also possible, and is usually due to resistance caused by a missense mutation in the squalene epoxidase enzyme targeted by the drug. Trichophyton resistance to terbinafine treatment is an emerging problem, and a switch to azole-based treatment may be necessary to cure such cases of onychomycosis.

Diagnostic utility of fractional exhaled nitric oxide in prolonged and chronic cough according to atopic status

BACKGROUND

Cough-variant asthma (CVA) and cough-predominant asthma (CPA) are the major causes of persistent cough in Japan. The utility of fractional exhaled nitric oxide (FeNO) measurement in the differential diagnosis of persistent cough has been reported, but the influence of atopic status, which is associated with higher FeNO levels, on the diagnostic utility of FeNO has been unknown.

METHODS

We retrospectively analyzed 105 non-smoking patients with prolonged and chronic cough that were not treated with corticosteroids and anti-leukotrienes.

RESULTS

CPA was diagnosed in 37 patients, CVA in 40, and non-asthmatic cough (NAC) in 28. FeNO levels were significantly higher in the CPA [35.8 (7.0-317.9) ppb] and CVA [24.9 (3.1-156.0) ppb] groups than in the NAC group [18.2 (6.9-49.0) ppb] (p < 0.01 by Kruskal-Wallis test). The optimal cut-off for distinguishing asthmatic cough (AC; CPA and CVA) from NAC was 29.2 ppb [area under the curve (AUC) 0.74, p < 0.01]. Ninety-one percent of subjects with FeNO levels ≥29.2 ppb had AC. Meanwhile, 40% of AC patients had FeNO levels <29.2 ppb. Stratified cut-off levels were 31.1 ppb (AUC 0.83) in atopic subjects vs. 19.9 ppb (AUC 0.65) in non-atopic subjects (p = 0.03 for AUC).

CONCLUSIONS

Although high FeNO levels suggested the existence of AC, lower FeNO levels had limited diagnostic significance. Atopic status affects the utility of FeNO levels in the differential diagnosis of prolonged and chronic cough.

Is allergic sensitization relevant in severe asthma? Which allergens may be culprit?

Severe asthma is a major health concern. The allergic (IgE-mediated) form of asthma is well known from a pathogenic viewpoint. We searched the available literature to identify which allergens are most frequently associated with severe, refractory or life threatening asthma. According to the results, molds, pet dander, cockroach and ragweed were more frequently responsible for severe asthma. Thunderstorm asthma, in addition, represents a special association between allergic sensitization and an external climatic factor. A detailed knowledge of the most harmful allergens is mandatory for an appropriate diagnostic and preventive approach.

Sensitization and cross-reactions of dermatophyte and Candida albicans allergens in patients with chronic urticaria

BACKGROUND

Chronic fungal infections are known to exacerbate allergic symptoms, including those of asthma and chronic urticaria (CU). We applied four prepared fungal antigens of Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum, and Candida albicans to examine sensitization to each in subjects with CU and onychomycosis and in healthy subjects, and to evaluate the etiologic role of dermatophytic infection in CU and observe any cross-reactions among these four antigens.

METHODS

Participants were divided into four groups, including those with CU with onychomycosis (experiment group), those with onychomycosis without allergic diseases (control group 1), those with CU without fungal infections (control group 2), and a healthy group (control group 3). In all subjects, skin prick tests with the four fungal antigens were performed. Subjects in the experiment group and control group 1 were also submitted to mycologic investigations.

RESULTS

The experiment group showed significantly higher rates of positivity than the three control groups to T. rubrum, E. floccosum, and T. mentagrophytes antigens. Control group 1 showed rates higher than those in control groups 2 and 3; no significant difference emerged between control groups 2 and 3. Positivity to the C. albicans antigen did not differ among the four groups. In control group 1, rates of positivity to the three dermatophytic antigens did not differ significantly but did for C. albicans.

CONCLUSIONS

Fungal infection seems to be an important determinant of trichophyton hypersensitivity. Cross-reactions among T. mentagrophytes, T. rubrum, and E. floccosum antigens were obvious, but none emerged between the antigens of the three dermatophytes and that of C. albicans.

CT-assessed large airway involvement and lung function decline in eosinophilic asthma: The association between induced sputum eosinophil differential counts and airway remodeling

OBJECTIVES

Eosinophilic asthma (EA) is a distinct clinical phenotype characterized by eosinophilic airway inflammation and airway remodeling. Few studies have used computed tomography (CT) scanning to assess the association between sputum eosinophil differential counts and airway involvement. We aimed to investigate the clinical characteristics and airway involvement of EA, and to examine the correlation between induced sputum eosinophil differential counts and CT-assessed airway remodeling.

METHODS

We retrospectively divided 63 patients with stable asthma receiving inhaled corticosteroids into 2 groups: 26 patients with EA (sputum eosinophil >3%) and 37 patients with non-eosinophilic asthma (NEA). Clinical measurements such as spirometry, fractional exhaled nitric oxide levels (FeNO), and CT-assessed indices of airway involvement were compared between the groups. Multivariate analysis was performed to identify determinants of the percentage of wall area (WA%).

RESULTS

The EA group had significantly longer asthma duration, lower pulmonary function, and higher FeNO than the NEA group. Also, the EA group had higher WA% and smaller airway luminal area than the NEA group. Sputum eosinophil differential counts and WA% were positively correlated. The multivariate linear regression analysis showed that the factors associated with WA% included sputum eosinophil differential counts, age, and body mass index. However, asthma duration was not associated with WA%. Our CT-assessed findings demonstrated large airway involvement in EA, and we observed a positive association between induced sputum eosinophil differential counts and WA%.

CONCLUSIONS

The findings indicate that induced sputum eosinophil differential counts may be associated with airway remodeling in patients with stable asthma.

The spectrum of allergic fungal diseases of the upper and lower airways

Fungi cause a wide spectrum of fungal diseases of the upper and lower airways. There are three main phyla involved in allergic fungal disease: (1) Ascomycota (2) Basidiomycota (3) Zygomycota. Allergic fungal rhinosinusitis (AFRS) causes chronic rhinosinusitis symptoms and is caused predominantly by Aspergillus fumigatus in India and Bipolaris in the United States. The recommended treatment approach for AFRS is surgical intervention and systemic steroids. Allergic bronchopulmonary aspergillosis (APBA) is most commonly diagnosed in patients with asthma or cystic fibrosis. Long term systemic steroids are the mainstay treatment option for ABPA with the addition of an antifungal medication. Fungal sensitization or exposure increases a patient's risk of developing severe asthma and has been termed severe asthma associated with fungal sensitivity (SAFS). Investigating for triggers and causes of a patient's asthma should be sought to decrease worsening progression of the disease.

Sensitization to fungal allergens: Resolved and unresolved issues

Exposure and sensitization to fungal allergens can promote the development and worsening of allergic diseases. Although numerous species of fungi have been associated with allergic diseases in the literature, the significance of fungi from the genera Alternaria, Cladosporium, Penicillium, Aspergillus, and Malassezia has been well documented. However, it should be emphasized that the contribution of different fungal allergens to allergic diseases is not identical, but species-specific. Alternaria and Cladosporium species are considered to be important outdoor allergens, and sensitization and exposure to species of these genera is related to the development of asthma and rhinitis, as well as epidemics of asthma exacerbation, including life-threatening asthma exacerbation. In contrast, xerophilic species of Penicillium and Aspergillus, excluding Aspergillus fumigatus, are implicated in allergic diseases as indoor allergens. A. fumigatus has a high capacity to colonize the bronchial tract of asthmatic patients, causing severe persistent asthma and low lung function, and sometimes leading to allergic bronchopulmonary aspergillosis. Malassezia are common commensals of healthy skin, although they are also associated with atopic dermatitis, especially on the head and neck, but not with respiratory allergies. Despite its importance in the management of allergic diseases, precise recognition of species-specific IgE sensitization to fungal allergens is often challenging because the majority of fungal extracts exhibit broad cross-reactivity with taxonomically unrelated fungi. Recent progress in gene technology has contributed to the identification of specific and cross-reactive allergen components from different fungal sources. However, data demonstrating the clinical relevance of IgE reactivity to these allergen components are still insufficient.

Atopic cough and fungal allergy

We have shown that some patients presenting with chronic bronchodilator-resistant non-productive cough have a global atopic tendency and cough hypersensitivity without nonspecific bronchial hyperresponsiveness, abbreviated as atopic cough (AC). The cough can be treated successfully with histamine H1 antagonists and/or glucocorticoids. Eosinophilic tracheobronchitis and cough hypersensitivity are pathological and physiological characteristics of AC. Fungus-associated chronic cough (FACC) is defined as chronic cough associated with basidiomycetous (BM) fungi found in induced sputum, and recognition of FACC has provided the possibility of using antifungal drugs as new treatment strategies. Bjerkandera adusta is a wood decay BM fungus, which has attracted attention because of its potential role in enhancing the severity of cough symptoms in FACC patients by sensitization to this fungus. Before making a diagnosis of "idiopathic cough" in cases of chronic refractory cough, remaining intractable cough-related laryngeal sensations, such as "a sensation of mucus in the throat (SMIT)," which is correlated with fungal colonization, should be evaluated and treated appropriately in each patient. The new findings, i.e., the detection of environmental mushroom spores that should not be present in the human airways in addition to the good clinical response of patients to antifungal drugs, may lead to the development of novel strategies for treatment of chronic cough.

Pathophysiological characteristics of asthma in the elderly: a comprehensive study

BACKGROUND

Comprehensive studies of the pathophysiologic characteristics of elderly asthma, including predominant site of disease, airway inflammation profiles, and airway hyperresponsiveness, are scarce despite their clinical importance.

OBJECTIVE

To clarify the pathophysiologic characteristics of elderly patients with asthma.

METHODS

Patients older than 65 years (elderly; n = 45) vs those no older than 65 years (nonelderly; n = 67) were retrospectively analyzed by spirometry, computed tomographic indices of large airway wall thickness and small airway involvement (air trapping), impulse oscillation measurements, exhaled nitric oxide levels, blood and induced sputum cell differentials, methacholine airway responsiveness, and total and specific serum IgE levels.

RESULTS

Elderly patients with asthma had significantly lower values for forced expiration volume in 1 second, mid-forced expiratory flow (percentage predicted), and ratio of forced expiration volume in 1 second to forced vital capacity than nonelderly patients with asthma (median 81.2% vs 88.8%, P = .02; 50.9% vs 78.6%, P = .03; 0.72 vs 0.78, P = .001, respectively). In computed tomographic measurements, elderly patients with asthma had significantly greater airway wall thickening and air trapping than nonelderly patients. Impulse oscillation measurements indicated that elderly patients with asthma showed significantly greater resistance at 5 Hz (used as an index of total airway resistance), greater decrease in resistance from 5 to 20 Hz, a higher ratio of decrease in resistance from 5 to 20 Hz to resistance at 5 Hz, higher integrated area between 5 Hz and frequency of resonance, greater frequency of resonance, and lower reactance at a frequency of 5 Hz (potential markers of small airway disease) than nonelderly patients. There were no significant differences in blood or sputum cell differentials, exhaled nitric oxide, or methacholine airway responsiveness between the 2 groups. Total serum IgE levels and positive rates of specific IgE antibodies against several allergens were significantly lower in elderly than in nonelderly patients with asthma.

CONCLUSION

Based on spirometric, computed tomographic, and impulse oscillation analyses, elderly patients with asthma have greater involvement of small and large airways than nonelderly patients with asthma.

Comprehensive efficacy of omalizumab for severe refractory asthma: a time-series observational study

BACKGROUND

Omalizumab, a humanized anti-IgE monoclonal antibody, is reportedly an effective treatment for severe allergic asthma. However, there have been few comprehensive analyses of its efficacy, including assessments of small airways or airway remodeling.

OBJECTIVE

To comprehensively evaluate the efficacy of omalizumab, including its effects on small airways and airway remodeling, in adult patients with severe refractory asthma.

METHODS

In this prospective, time-series, single-arm observational study, 31 adult patients with severe refractory asthma despite the use of multiple controller medications, including high-dose inhaled corticosteroids (1,432 ± 581 μg/d of fluticasone propionate equivalent), were enrolled. Clinical variables, including Asthma Quality of Life Questionnaire, asthma exacerbations, exhaled nitric oxide, pulmonary function, methacholine airway responsiveness, induced sputum, and chest computed tomogram, were assessed at baseline and after 16 and 48 weeks of treatment with omalizumab.

RESULTS

Twenty-six of the 31 patients completed 48 weeks of treatment. For these patients, Asthma Quality of Life Questionnaire scores and peak expiratory flow values significantly and continuously improved throughout the 48 weeks (P < .001 for all comparisons). Unscheduled physician visits, asthma exacerbations requiring systemic corticosteroids, fractional exhaled nitric oxide at 50 mL/s and alveolar nitric oxide levels, sputum eosinophil proportions, and airway-wall thickness as assessed by computed tomography significantly decreased at 48 weeks (P < .05 for all comparisons).

CONCLUSION

Omalizumab was effective for adult patients with severe refractory asthma. Omalizumab may have anti-inflammatory effects on small airways and reverse airway remodeling.

TRIAL REGISTRATION

UMIN000002389.

Fungal allergy in asthma-state of the art and research needs

Sensitization to fungi and long term or uncontrolled fungal infection are associated with poor control of asthma, the likelihood of more severe disease and complications such as bronchiectasis and chronic pulmonary aspergillosis. Modelling suggests that >6.5 million people have severe asthma with fungal sensitizations (SAFS), up to 50% of adult asthmatics attending secondary care have fungal sensitization, and an estimated 4.8 million adults have allergic bronchopulmonary aspergillosis (ABPA). There is much uncertainty about which fungi and fungal allergens are relevant to asthma, the natural history of sensitisation to fungi, if there is an exposure response relationship for fungal allergy, and the pathogenesis and frequency of exacerbations and complications. Genetic associations have been described but only weakly linked to phenotypes. The evidence base for most management strategies in ABPA, SAFS and related conditions is weak. Yet straightforward clinical practice guidelines for management are required. The role of environmental monitoring and optimal means of controlling disease to prevent disability and complications are not yet clear. In this paper we set out the key evidence supporting the role of fungal exposure, sensitisation and infection in asthmatics, what is understood about pathogenesis and natural history and identify the numerous areas for research studies.

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.

Impact of Schizophyllum sensitization on decline of lung function in asthma

OBJECTIVE

There is increasing interest in the association between the severity of asthma and fungal sensitization, and lung function decline in relation to mold and dampness in the home has recently been reported. This study was performed to determine the correlation between sensitization to Schizophyllum commune and decline of lung function, and to elucidate the outcomes and risk factors, especially from Schizophyllum allergy.

METHODS

The medical records of 50 patients with asthma who satisfied the following inclusion criteria were collected and reviewed retrospectively: (1) at least 5 years of follow-up with five evaluations; (2) intradermal skin tests including S. commune performed at the initial assessment; and (3) severity ranging from mild-to-moderate. Lung function decline (evaluated as adjusted delta FEV1/year) was compared in a cross-sectional manner with regard to gender, age, BMI, smoking habit, allergological characteristics and exacerbation frequency.

RESULTS AND CONCLUSIONS

There were significant differences in lung function decline between females and males (p < 0.05), positive and negative results of late-phase skin reaction to S. commune (p < 0.001), and positive and negative late-phase skin reaction to Aspergillus (p < 0.05). Lung function decline was correlated with exacerbation frequency (r = 0.428, p = 0.002). On multiple regression analysis, the probability of lung function decline in asthma was found to be significantly associated with female gender and positive late-phase skin reaction against S. commune. Our results suggested that sensitization to S. commune may be one of the risk factors involved in lung function decline in asthmatic patients.

Correlation between fungal sIgE and bronchial asthma severity

Fungal sensitisation is closely associated with asthma; however, the correlation between fungi and asthma severity remains unclear. The aim of this study was to investigate the severity of asthma in 100 patients with asthma due to fungal and non-fungal allergens. A total of 100 outpatients and inpatients with asthma were selected from 2010 to 2011 and were divided into three groups (mild, moderate and severe) according to their clinical manifestations, lung function results and treatment situations. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of specific immunoglobulin E (sIgE) to five fungal allergens and seven non-fungal allergens in the serum of all patients. The levels of sIgE to Aspergillus, Penicillium and Candida albicans allergens in the severe group were significantly higher compared with those in the moderate and mild groups (P<0.001 and P<0.05, respectively); those of the moderate group were significantly higher compared with those of the mild group (P<0.05). No significant difference was observed for the levels of sIgE to Alternaria alternata among the three groups. sIgE to Cladosporium herbarum was not present for all three groups. No significant difference was observed for the levels of sIgE to non-fungal allergens among the three groups. Fungal allergens are closely correlated with the severity of asthma, whereas non-fungal allergens are not.

The role of allergy in severe asthma

The classification of asthma to identify forms which have different contributing causes is useful for all cases in which the disease requires regular treatment, but it is essential for the management of severe asthma. Many forms of the disease can occur, and complex mixtures are not uncommon; here we artificially separated the cases into four groups: (i) inhalant allergy, (ii) fungal sensitization with or without colonization (including ABPA); (iii) severe sinusitis with or without aspirin-exacerbated respiratory disease (AERD), and (iv) non-inflammatory cases, including those associated with severe obesity and vocal cord dysfunction (VCD). The reason for focusing on these groups is because they illustrate how much the specific management depends upon correct classification. Inhalant allergy can present as chronically severe asthma. However, severe attacks of asthma requiring hospital admission can occur in cases which are generally only mild or moderate. The best recognized and probably the most common cause of these acute episodes is acute infection with a rhinovirus. Recent evidence suggests that high titre IgE, particularly to dust mite, correlates to exacerbations of asthma related to rhinovirus infection. Although it is well recognized that the fungus Aspergillus can colonize the lungs and cause severe disease, it is less well recognized that those cases may not have full criteria for diagnosis of ABPA or may involve other fungi. Identifying fungal cases is important, because treatment with imidazole antifungals can provide significant benefit. Taken together, specific treatment using allergen avoidance, immunotherapy, anti-IgE, or antifungal treatment is an important part of the successful management of severe asthma, and each of these requires correctly identifying specific sensitization.

Current treatment of severe asthma

Severe asthma is considered a heterogeneous disease in which a variety of clinical, physiological and inflammatory markers determine disease severity. Pivotal studies in the last 5 years have led to substantial progress in many areas, ranging from a more accurate definition of truly severe, refractory asthma, to classification of the disease into distinct clinical phenotypes, and introduction of new therapies. This review focuses on three common clinical phenotypes of severe asthma in adults (early onset severe allergic asthma, late onset non-atopic eosinophilic asthma, late onset non-eosinophilic asthma with obesity), and provides an overview of recent developments regarding treatment options that are best suited for each of these phenotypes.

Severe asthma with fungal sensitization

A new phenotype of asthma has been described recently, namely severe asthma with fungal sensitization (SAFS). SAFS can be conceptualized as a continuum of fungal sensitization, with asthma at one end and allergic bronchopulmonary aspergillosis at the other. It is diagnosed by the presence of severe asthma, fungal sensitization, and exclusion of allergic bronchopulmonary aspergillosis. Because of the paucity of data and ambiguity in diagnostic criteria, SAFS is currently more of a diagnosis of exclusion than a specific entity. Treatment of SAFS initially should be similar to that of severe asthma, including the use of omalizumab. The potential role of itraconazole as a specific therapy in SAFS requires more evidence before it can be incorporated in routine practice. An urgent need exists for data regarding the prevalence, natural history, and clinical relevance of SAFS so that its exact characterization and importance as a specific subtype of asthma can be clearly defined. This review summarizes the current understanding of the pathogenesis, diagnosis, and management of SAFS.

The influence of Schizophyllum commune on asthma severity

BACKGROUND

The sensitization and exposure to fungal allergens have been reported to be associated with asthma. The aim of this study was to clarify the impact of sensitization to Schizophyllum commune (S. commune) on the severity and exacerbations of asthma.

METHODS

Ninety-two patients with asthma of various levels of severity [mild (n = 18), moderate (28), and severe (46)] and exacerbation severity [moderate (n = 43) and severe (6)] were retrospectively examined with regard to fungal sensitization such as specific IgE or intradermal skin reactions against S. commune and other common allergens. We also classified the patients into three groups: (1) three or more asthma attacks during the past year (F-BA) (n = 29),(2) one or two asthma attacks (NF-BA) (n = 20), and (3) no asthma attack (C-BA) (n = 43).

RESULTS

The positive rate of late cutaneous reactions to S. commune was higher in patients with severe asthma (41.2%) than with moderate (26.1%) or mild asthma (6.7%), and was significantly different among the three groups (P < 0.05). Although the ratio did not show a significant difference between the patients with severe (83.3%) or moderate (36.1%) exacerbation, it was higher in F-BA (60.9%) than in NF-BA (21.1%) and C-BA patients (10.0%), and it was significantly different among the three groups (P = 0.0002). Multivariate analysis identified positive results for late-phase skin reactions to S. commune and the age of the patients as an independent determinant of asthma severity, and the skin results and %FVC an independent determinant of exacerbation frequency.

CONCLUSION

This study demonstrated that S. commune is an environmental fungus that appears to enhance both the severity of asthma and the exacerbation frequency.

Two cases of Schizophyllum asthma: is this a new clinical entity or a precursor of ABPM?

BACKGROUND

There is a close link between fungal sensitization and asthma severity. Although Schizophyllum commune (S. commune, "suehirotake" in Japanese), one of the basidiomycetous (BM) fungi, is a fungus that can cause allergic bronchopulmonary mycosis (ABPM) and allergic fungal sinusitis (AFS), whether the fungus causes or sensitizes subjects to asthma is unclear.

METHODS

The bronchial provocation test using S. commune antigen was performed in two asthmatics who had demonstrated positive skin reactions to the S. commune antigen, and low dose of itraconazole (50 mg/day) was prescribed as an adjunctive therapy for 2 weeks. The allergological features and clinical manifestations of these patients are herein evaluated and discussed.

RESULTS

Case 1 was a 71-year-old female, and case 2 was a 69-year-old male. Both patients demonstrated positive reactions to the inhalation test. A diagnosis of AFS or ABPM was excluded in both patients because of the lack of a history of pulmonary infiltrates, central bronchiectasis, a history of expectoration of brown plugs or flecks, or sinusoidal findings. Although the efficacy of itraconazole in our cases was unclear, the elevated titer of the specific IgG-for S. commune in case 2 gradually decreased during the period of antifungal therapy.

CONCLUSIONS

The two patients described herein were diagnosed to have bronchial asthma caused by S. commune; so-called Schizophyllum asthma. S. commune may also be a causative fungal antigen of bronchial asthma.

The role of anti-infectives in the treatment of refractory asthma

Refractory asthma not only has a significant effect on quality of life, but also imposes an economic burden on society. Increasing evidence suggests that there is a pathophysiologic interaction between infection and allergic disease in patients with severe or refractory asthma. Therapeutic trials of macrolides and azoles are being utilized in some patients with refractory asthma who fail to respond to standard therapy. In this article we review the definition of refractory asthma and the potential pathophysiologic interactions between infection and allergic disease. Emerging data suggest that microorganisms and their byproducts may be a therapeutic target in the therapy of patients with severe or refractory asthma.

Infections and asthma: new insights into old ideas

A relationship between infections and allergic airway disease has long been recognized, and many reviews have been written on this topic. However, both clinical and basic science studies published in the last 3 years provide new insights into the relationship between infection and allergic conditions. In this review, we focus on these very recent studies, which address the role of infection in the development, maintenance, and exacerbation of asthma. Bacterial, viral, fungal, and parasitic infections have each been examined and provide a framework for these novel concepts.

Inflammatory subtypes in cough-variant asthma: association with maintenance doses of inhaled corticosteroids

BACKGROUND

Sputum cell-subtype profiles in cough-variant asthma (CVA) are unknown.

METHODS

Ninety-eight inhaled corticosteroid (ICS)-naive CVA patients were classified according to sputum eosinophil (eos)/neutrophil (neu) counts, as reported in subjects with asthma, as eosinophilic (E) (eos ≥ 1.0%, neu < 61%; n = 28), neutrophilic (N) (eos < 1.0%, neu ≥ 61%; n = 31), mixed granulocytic (M) (eos ≥ 1.0%, neu ≥ 61%; n = 12), and paucigranulocytic (P) (eos < 1.0%, neu < 61%; n = 27) subtypes. Patient characteristics; sputum levels of eosinophil cationic protein (ECP), IL-8, and neutrophil elastase (NE); and daily ICS doses required to maintain control during follow-up (6, 12, 18, and 24 months) were compared, retrospectively.

RESULTS

Subtype N patients, predominantly women, were marginally older than the other subtypes, but FEV(1), airway responsiveness, and total and specific IgE results did not differ. ECP levels were higher in M and E than in N and P subtypes, being similar between M and E or N and P subtypes. Levels of IL-8 and NE were higher in M than in other subtypes, being similar among the latter. ICS doses were initially similar in all subtypes (800 μg equivalent of beclomethasone) but were higher in M than in N and P subtypes throughout follow-up, with E being intermediate between M and N or P subtypes. ICS doses decreased (halved or quartered) in E, N, and P patients followed for 24 months (P < .0001 for all) but remained unchanged in M subjects. IL-8 and NE levels correlated positively with ECP levels.

CONCLUSIONS

In addition to eosinophils, neutrophils, which are possibly activated in the presence of eosinophils, may participate in the pathophysiology of CVA.

Severe asthma and fungi: current evidence

Bronchial asthma is an inflammatory disease of the airways which may be worsened due to numerous extrinsic factors. The most common trigger is continuous exposure to allergens of which fungal agents are important factors. There is overwhelming evidence for the presence of fungal sensitization in patients with asthma. The diagnosis of fungal sensitization can be made either with skin testing with antigens derived from fungi or measuring specific IgE levels. There is also a strong association between fungal sensitization and severity of asthma. Whether this relationship is causal or just casual remains to be investigated. A variety of fungi are known to cause sensitization in asthmatics, but the most important fungal agent(s) causing severe asthma with fungal sensitization (SAFS) are currently unknown. Aspergillus species seem to be the strongest candidates as only with Aspergillus spp. does one encounter two extreme immunologic phenomena, i.e., the Aspergillus-sensitive asthma and allergic bronchopulmonary aspergillosis. The initial clinical management of SAFS should be the same as asthmatics without fungal sensitization. There is some evidence of the role of itraconazole in the management of SAFS but its routine use in SAFS requires further evaluation. This review summarizes the current evidence on the link between fungi and severe asthma.

The importance of basidiomycetous fungi cultured from the sputum of chronic idiopathic cough: a study to determine the existence of recognizable clinical patterns to distinguish CIC from non-CIC

BACKGROUND

Recently we have reported 5 cases of allergic fungal cough (AFC), which is intractable and is characterized by sensitization to one of basidiomycetous fungus. Because AFC shows good clinical response to antifungal drugs, diagnosing AFC in patients with CIC may lead to the consequent management of CIC. Therefore, we determined the incidence of CIC among our hospital patients, and the frequency of BM fungi in sputum samples collected from patients with CIC. Furthermore we evaluated whether or not a recognizable clinical pattern that distinguishes CIC from non-CIC exists.

METHODS

The medical records of 70 patients complaining of chronic cough who were referred to our hospital for diagnosis and treatment were analyzed retrospectively.

RESULTS

The primary diagnoses were CIC (27.0%), cough-variant asthma (30.0%), atopic cough (24.3%), sinobronchial syndrome (8.6%), cough-predominant asthma (7.1%), gastro-esophageal reflux (1.4%), and others (1.4%). In CIC patients, the median age, proportion of females, and frequency of acute upper respiratory tract infection did not differ significantly from those in non-CIC patients. CIC patients had a longer median duration of cough (11.0 months vs. 3.5 months). The positive ratio of BM cultured from the sputa of CIC patients (62.5%) was significantly (p=0.0061) higher than that of non-CIC patients (16.7%).

CONCLUSION

The existence of BM fungi in induced sputum may be an important factor for distinguishing the clinical manifestation of CIC from that of non-CIC. The clinical approach from the aspect of fungal allergy may serve as a clue that may aid in the successful management of CIC.