Evaluation of the association between sensitization to common inhalant fungi and poor asthma control

Aeroallergen sensitization patterns among patients with chronic rhinitis with or without concomitant asthma

OBJECTIVES

The aim of this study was to explore the differences in the pattern of allergen sensitization in CR individuals without or with asthma, according to asthma severity.

METHODS

A total of 1066 adults were evaluated. Asthma and chronic⁄allergic rhinits were identified by specialists, questionnaries and skin-prick test. The phenotypic characterization was avaliable from skin-prick test to an aeroallergen extended panel, total IgE and pulmonary function. Using questionnaires and clinical evaluation, participants were classified into the groups: chronic rhinitis alone (CRA) and chronic rhinitis + asthma, the latter subdivided into CR + mild asthma (CRMA) and CR + moderate to severe asthma (CRMSA). Aerollergen sensitization was defined by a positive prick test to one or more allergens associated with nasal symptoms and/or asthma. The association between CR and asthma was evaluated by multivariable logistic regression. The evidence of effect modification of pattern of sensitization in CR on the association with asthma severity and outcomes was examined by introducing interactions terms in the logistic regression models adjusting for confounders.

RESULTS

Frequency of sensitization to aeroallergens was higher in association with asthma in comparison to CRA (CRMA 70.4%; CRMSA 65.0%; CRA 47.0%; p = 0.000). Similarly, the presence of asthma was associated to aeroallergen multiple sensitization (51.5%) (OR = 2.10, 95% CI 1.27-3.50). Additionally, the sensitization to mites, cockroaches, animal epithelium, grasses, and molds, were higher in asthma (56.8%, 24.3%, 12%, 7.13% and 10.3%, respectively). Sensitization to Alternaria alternata, Cladosporium herbarum and dog epithelium was exclusive in asthma groups. A concomitant asthma diagnosis was directly associated with a positive allergen sensitization at least one allergen (62.7%, OR = 2.45, 95% CI 1.80-3.34) and polissensitization (51.5%, OR = 2.10, 95% CI 1.27-3.50).

CONCLUSION

Asthma is associated with multiple allergen sensitization among patients with CR. Some unique profiles of aeroallergen sensitization were observed in patients with CR and asthma. Nevertheless, no difference was found in the sensitization in relation to asthma severity, which suggest atopy is not the main underlying mechanism for asthma severity among patients with CR.

LEVEL OF EVIDENCE

Level 3.

Fungal allergen sensitization: Prevalence, risk factors, and geographic variation in the United States

BACKGROUND

Many fungal species are associated with the pathogenesis of allergic disease, yet most epidemiologic studies on IgE-mediated fungal sensitization have only included a few species.

OBJECTIVE

We investigated fungal allergen sensitization prevalence, risk factors, and geographic variation in the United States.

METHODS

From 2014 to 2019, a total of 7,912,504 serum-specific IgE (sIgE) test results for 17 fungal species were measured in 1,651,203 patients aged 0-85 years by a US-wide clinical laboratory. Fungal sensitization prevalence, patterns, and relationship with demographic characteristics, clinical diagnoses, and geographic regions were analyzed.

RESULTS

Twenty-two percent of patients were positive (sIgE > 0.10 kUA/L) to at least 1 fungal allergen; 13.7% were positive to >2 fungal allergens. Fungal species-specific positivity rates ranged 7.4-18.6% and were highest for Candida albicans (18.6%), Alternaria alternata (16.6%), Stemphylium herbarum (14.9%), and Aspergillus fumigatus (14.2%). Other fungi that were frequently tested had relatively low positivity rates (eg, Cladosporium herbarum 11.1%, Penicillium chrysogenum 10.7%). Independent risk factors for test positivity for all fungal species included male sex, teen age (highest in those aged 10-19 years), atopic dermatitis, and asthma. Fungal sensitization was generally higher in urban areas and ecoregions composed predominantly of grasslands and prairies compared to woodlands and forest, although there was greater variation in sensitization risk to different fungi in different ecoregions.

CONCLUSION

Independent risk factors for fungal sensitization include male sex, teen ages, atopic dermatitis, asthma, and ecoregion.

Allergy to fungi: Advances in the understanding of fungal allergens

Allergic diseases are a major health problem due to their increasing incidence and high prevalence worldwide. Asthma has several aetiologies, and allergy plays an important role in its development in approximately 60% of adults and 80% of children and adolescents. Although the link between aeroallergen sensitization and asthma exacerbations has been long recognized, the investigations of the triggering allergens may be superficial in many asthma cases. The main allergenic sources related to asthma, and other allergic diseases, are pollens, mites, fungi, and animal epithelia. Fungi are considered the third most frequent cause of respiratory pathologies. Asthma caused by several fungi species may have a bad prognosis in some cases due to its severity and difficulty in avoidance methods. Despite the recognised relevance of fungi in respiratory allergies, the knowledge about fungal allergens seems to be scarce, with few descriptions of new allergens, compared to other allergenic sources. The study of major, minor, and cross-reactive fungal allergens, and their relevance in the allergic disease, might be crucial, not only to accurately diagnose these allergies, but also to predict exacerbations and responses to therapies, as well as for the development of personalized treatment plans in a fast-changing climate scenario.

Prevalence of Aspergillus Sensitization and Allergic Bronchopulmonary Aspergillosis in Adults With Bronchial Asthma: A Systematic Review of Global Data

BACKGROUND

The prevalence of allergic bronchopulmonary aspergillosis (ABPA) in asthmatic patients remains unclear and is likely different across geographic locales.

OBJECTIVE

To systematically review the literature for estimating the prevalence of Aspergillus sensitization (AS) and ABPA in adults with bronchial asthma.

METHODS

We searched the PubMed and Embase databases for studies reporting the prevalence of AS or ABPA in at least 50 asthmatic subjects. The primary outcome was to assess the prevalence of ABPA. The secondary outcome was to evaluate the prevalence of AS in asthma and that of ABPA in asthma with AS. We pooled the prevalence estimates using a random-effects model and examined the factors influencing the prevalence using multivariate meta-regression.

RESULTS

Of the 11,801 records retrieved, 86 studies with 25,770 asthmatic subjects met the inclusion criteria. Most of the studies were from tertiary care centers. The pooled prevalence of ABPA in asthma (47 studies; 9822 asthmatic subjects) was 11.3% (95% CI, 8.7-14.2). The pooled prevalence of AS in asthma (73 studies; 23,003 asthmatic subjects) was 25.1% (95% CI, 20.5-30.0), whereas the prevalence of ABPA in AS (36 studies; 2954 asthmatic subjects) was 37.0% (95% CI, 27.9-46.6). Multivariate meta-regression identified studies published from India (odds ratio, 1.11; 95% CI, 1.01-1.23) as the only factor associated with higher ABPA prevalence. There was presence of significant statistical heterogeneity and publication bias.

CONCLUSIONS

We found a high prevalence of ABPA in adult asthmatic subjects, underscoring the need for screening for ABPA in all asthmatic subjects seeking tertiary care.

The Mediating Effect of Cytokines on the Association between Fungal Sensitization and Poor Clinical Outcome in Asthma

Sensitization to fungal allergens is one of the proposed phenotypes in asthma. An association between fungal sensitization and worse clinical outcomes is apparent. Moreover, fungal sensitization in asthma that is associated with different type of immunological mechanism has been reported. How the role of cytokines mediates the association between fungal sensitization and poorer asthmatic outcomes remains unclear. We aimed to determine role of cytokines in the relationship between fungal sensitization and worse clinical outcomes in asthma.

METHOD

We conducted a prospective study to recruit adult patients with asthma. Data including age, sex, height, weight, smoking history, medication, emergency visit and admission, pulmonary function testing result, and Asthma Control Test (ACT) scores were collected. We used the automated BioIC method to measure fungal allergen sIgE in sera. Serum levels of Interleukin (IL) -4, IL-13, IL-6, IL-9, IL-10, IL-17 A, IL-22, Interferon (IFN) -γ, Immunoglobulin E (IgE), Tumor necrosis factor-α (TNF-α), and Transforming growth factor-β (TGF-β) were measured using ELISA.

RESULT

IL-6 and IL-17A had a significant positive correlation between sensitization and most fungi species compared to IgE. Sensitization to Candida albicans had strongly positive association both with IL-6 and IL-17A. However, only IL-17A had significant relationship with ED visit times. The mediation analysis result indicates that IL-17A had a significant positively mediating effect (ME) on the association between Candida albicans and ED visit times.

CONCLUSION

IL-17A is a potential mediator to link Candida albicans sensitization and ED visits for asthma. We suggest that patients with fungal sensitization, such as Candida albicans, have poorer outcomes associated with Th17-mediated immune response rather than Th2.

Association between house dust mites sensitization and level of asthma control and severity in children attending Mansoura University Children’s Hospital

Background

House dust mites (HDM) are considered as a major source of indoor aeroallergen all over the world that precipitate allergic reactions including rhinoconjunctivitis, food allergy, atopic dermatitis, and allergic asthma. In this study, we aimed to assess the clinical and laboratory profile of some Egyptian asthmatic children who are sensitized to house dust mites and determine the association of HDM sensitization and severity of asthma according to recent GINA guidelines.

Results

The most frequent clinical phenotype among the HDM-positive group was a cough (96.7%), while the clinical phenotypic wheeze was frequent in HDM negative group (96.7%). There is a statistically significant difference between studied cases classified according to sensitivity to HDM regarding level of asthma control (50.0% were uncontrolled among cases sensitive to HDM and 56.7% of cases non-sensitive to HDM were controlled (p = 0.001*). Severity according to treatment results was significantly higher among cases sensitive to HDM (26.7% of cases sensitive to HDM versus 3.3% of cases non-sensitive to HDM), p = 0.017.

Conclusions

HDM sensitization is associated mainly with cough asthma phenotype and allergic rhinitis in our studied cases. HDM sensitization increases asthma severity and decreases the ability to control asthma symptoms.

Trial registration

ClinicalTrial.gov, NCT04958616.

Allergic fungal airways disease (AFAD): an under-recognised asthma endotype

The term allergic fungal airways disease has a liberal definition based on IgE sensitisation to thermotolerant fungi and evidence of fungal-related lung damage. It arose from a body of work looking into the role of fungi in asthma. Historically fungi were considered a rare complication of asthma, exemplified by allergic bronchopulmonary aspergillosis; however, there is a significant proportion of individuals with Aspergillus fumigatus sensitisation who do not meet these criteria, who are at high risk for the development of lung damage. The fungi that play a role in asthma can be divided into two groups; those that can grow at body temperature referred to as thermotolerant, which are capable of both infection and allergy, and those that cannot but can still act as allergens in IgE sensitised individuals. Sensitisation to thermotolerant filamentous fungi (Aspergillus and Penicillium), and not non-thermotolerant fungi (Alternaria and Cladosporium) is associated with lower lung function and radiological abnormalities (bronchiectasis, tree-in-bud, fleeting shadows, collapse/consolidation and fibrosis). For antifungals to play a role in treatment, the focus should be on fungi capable of growing in the airways thereby causing a persistent chronic allergenic stimulus and releasing tissue damaging proteases and other enzymes which may disrupt the airway epithelial barrier and cause mucosal damage and airway remodelling. All patients with IgE sensitisation to thermotolerant fungi in the context of asthma and other airway disease are at risk of progressive lung damage, and as such should be monitored closely.

Moulds and Staphylococcus aureus enterotoxins are relevant allergens to affect Type 2 inflammation and clinical outcomes in chronic rhinosinusitis patients

Background

Sensitisation to moulds and Staphylococcus aureus enterotoxins (SEs) is associated with the pathophysiology of both asthma and chronic rhinosinusitis (CRS). The purpose of this study was to clarify the contribution of sensitisation to these allergens to Type 2 inflammation in the blood, nose and the lower airways, and clinical outcomes in CRS patients.

Methods

We prospectively enrolled 56 CRS patients who underwent endoscopic sinus surgery (ESS) (20 with comorbid asthma) and 28 healthy controls between October 2015 and December 2017. CRS patients were followed up for 12 months after surgery. Type 2 inflammation-related biomarkers were analysed using blood, resected tissue samples and sputum. 10 allergens including Alternaria, Aspergillus and SEs were measured. Type 2 inflammation-related biomarkers and clinical outcomes were compared in the stratification with the presence or absence of allergen sensitisation.

Results

Sensitisation rate to moulds and SEs in asthmatic patients was increased when changing the cut-off value of specific IgE titre from 0.35 UA·mL⁻¹ to 0.10 UA·mL⁻¹ (1.7- and 4.5-fold, respectively). Moulds and SEs affected the prevalence of asthma and eosinophilic CRS by interacting with each other. All Type 2 inflammation-related biomarkers except for eosinophils in sinus tissue were significantly higher in patients with mould or SE (mould/SE) sensitisation (≥0.10 UA·mL⁻¹) (n=19) than in those without (n=37) and healthy subjects (all p<0.05). Meanwhile, mould/SE sensitisation did not affect longitudinal changes in clinical outcomes after ESS. Changes in serum mould/SE-IgE levels after ESS remained unclear.

Conclusion

Mould/SE sensitisation (≥0.10 UA·mL⁻¹) may affect the development of Type 2 inflammation and clinical outcomes in CRS patients.

Alternaria,Aspergillusand S. aureus enterotoxins are important allergens affecting Type 2 inflammation and clinical outcomes in CRS patients. Sensitisation to moulds/SEs (≥0.10 UA·mL⁻¹) would be meaningful in the pathophysiology of CRS.https://bit.ly/3bUG8ZT

Kids, Difficult Asthma and Fungus

Fungi have many potential roles in paediatric asthma, predominantly by being a source of allergens (severe asthma with fungal sensitization, SAFS), and also directly damaging the epithelial barrier and underlying tissue by releasing proteolytic enzymes (fungal bronchitis). The umbrella term ‘fungal asthma’ is proposed for these manifestations. Allergic bronchopulmonary aspergillosis (ABPA) is not a feature of childhood asthma, for unclear reasons. Diagnostic criteria for SAFS are based on sensitivity to fungal allergen(s) demonstrated either by skin prick test or specific IgE. In children, there are no exclusion criteria on total IgE levels or IgG precipitins because of the rarity of ABPA. Diagnostic criteria for fungal bronchitis are much less well established. Data in adults and children suggest SAFS is associated with worse asthma control and greater susceptibility to asthma attacks than non-sensitized patients. The data on whether anti-fungal therapy is beneficial are conflicting. The pathophysiology of SAFS is unclear, but the epithelial alarmin interleukin-33 is implicated. However, whether individual fungi have different pathobiologies is unclear. There are many unanswered questions needing further research, including how fungi interact with other allergens, bacteria, and viruses, and what optimal therapy should be, including whether anti-neutrophilic strategies, such as macrolides, should be used. Considerable further research is needed to unravel the complex roles of different fungi in severe asthma.

The Pathogenesis of Fungal-Related Diseases and Allergies in the African Population: The State of the Evidence and Knowledge Gaps

The prevalence of allergic diseases in the African continent has received limited attention with the allergic diseases due to fungal allergens being among the least studied. This lead to the opinion being that the prevalence of allergic disease is low in Africa. Recent reports from different African countries indicate that this is not the case as allergic conditions are common and some; particularly those due to fungal allergens are increasing in prevalence. Thus, there is need to understand both the aetiology and pathogenies of these diseases, particularly the neglected fungal allergic diseases. This review addresses currently available knowledge of fungal-induced allergy, disease pathogenesis comparing findings from human versus experimental mouse studies of fungal allergy. The review discusses the potential role of the gut mycobiome and the extent to which this is relevant to fungal allergy, diagnosis and human health.

Long-term effect of antifungal therapy for the treatment of severe resistant asthma: an active comparator clinical trial

Background and Purpose:

Itraconazole therapy has been reported to control asthma in severe therapy-resistant asthma with fungal sensitization. The aim of this study was to investigate the impact of anti-fungal therapy on the treatment of severe asthma, irrespective of sensitization.

Materials and Methods:

This active comparator clinical trial was performed on 110 therapy-resistant asthmatic patients who were randomly assigned into two groups of case and control. The patients in the case group were administered 200 mg itraconazole twice a day and the control group received 10 mg prednisolone after breakfast for 4 months. The asthma control test (ACT) which was used as a marker for the global evaluation of treatment effectiveness (GETE) was applied as the primary endpoint parameter. Cough, dyspnea, and sleep disturbance were measured on a scale of 1-4, with 1 representing no symptom and 4 indicating severe exhausting disturbance.

Results:

Based on the obtained results, 71% of the itraconazole group demonstrated a marked improvement in the GETE score after a four-month treatment. Itraconazole was able to suppress clinical symptoms, including cough, dyspnea, and night symptoms, and their physical exam was indicative of normalization in 60% of the patients. On the other hand, the patients in the parallel group "prednisolone" were only able to control dyspnea. The ACT score represented a notable improvement with itraconazole (mean: 14 before the trial and >20 after the trial) and spirometry parameters underwent a considerable change from obstructive pattern to normal. Furthermore, adverse effects were only detected in 6% of itraconazole users.

Conclusion:

The results of this clinical trial indicted the effectiveness of antifungal therapy for the control of the clinical condition of a subgroup of patients with severe steroid-refractory asthma.

The Impact of Ambient Environmental Exposures to Microbial Products on Asthma Outcomes from Birth to Childhood

Purpose of Review

Asthma is a chronic respiratory condition with increasing domestic and worldwide prevalence that burdens individuals and the healthcare system with high costs associated with long-term treatments and acute emergency room (ER) visits. It can be triggered by ambient microbes, including bacteria, viruses, and fungi. In this review, we examine the outcomes of asthma patients in relation to environmental exposures to ambient microbe products, focusing on whether exposure leads to asthma development from birth to childhood and if particular microbes are associated with worsened asthma exacerbations.

Recent Findings

Bacterial endotoxin is more prominent in homes with pets and may cause cytokine cascades that lead to asthma exacerbation. However, some studies have demonstrated a protective effect with early exposure. Patients with positive Aspergillus skin testing are more prone to moderate-severe or severe-uncontrolled asthma. Fungal sensitization is also associated with earlier onset of asthma and demonstrates a dose-dependent relationship of symptom severity and duration. Among viruses, rhinovirus has the greatest association with decreased lung function, severe asthma, and asthma-related hospital admissions. Distribution of microbial products and associated asthma symptoms depends on the geographical climate. Genetic variations among individuals also mitigate the effects of microbial products on asthma development and symptom severity.

Summary

Microbial products of bacteria, fungi, and viruses are associated with the development of asthma, more severe asthma symptoms, and worse outcomes. However, some early exposure studies have also demonstrated a protective effect. Bacterial and fungal products are related to decreased lung function and earlier onset of asthma. Viral products are related to asthma-associated hospital admissions; and the climate and patient genetics can also temper or intensify the relationships between microbial products, asthma development, and asthma symptom severity. Further research should focus on the effects of early microbe exposure and its interaction with human immune systems and asthma-related outcomes.

[Allergic respiratory diseases related to mould in the home]

Exposure to mould is a potential risk factor for asthma in both adults and children. In adult, the relation between exposure, sensitization and symptoms has been demonstrated in severe asthmatics sensitized to Alternaria. For children, exposure to mould in childhood is a risk factor for asthma in both atopic and non-atopic individuals. Exposure or sensitization to moulds are a risk factor for severe asthma and/or exacerbations in children. There appears to be a causal relationship between exposure and asthma. This link seems less significant in adults. However, in adults mould sensitive asthma seems to determine a phenotype of severe asthma associated with more marked obstructive lung disease. Moulds can stimulate either innate or the acquired immunity. They are responsible for a marked Th2 inflammation leading to more severe asthma. Besides the immunological mechanisms, toxic mechanisms can also intervene. It is therefore not correct to reduce the effect of moulds, particularly in respiratory symptoms, to only allergic mechanisms.

The effect of temperature on airborne filamentous fungi in the indoor and outdoor space of a hospital

Fungi are one of the bioaerosols in indoor air of hospitals. They have adverse effects on staff and patients. The aim of this study was to investigate the effects of three incubation temperature on the density and composition of airborne fungi in an indoor and outdoor space of hospital. Sabouraud dextrose agar was used for culture the fungi. For improvement of aseptic properties, chloramphenicol was added to this medium. The density of airborne fungi was less than 282 CFU/m³. The highest density was detected in emergency room and the lowest of them was in neonatal intensive care unit (NICU) and operation room (OR). Results showed that fungi levels at 25 °C were higher than 37 and 15 °C (p = 0.006). In addition, ten different genera of fungi were identified in all departments. The predominant fungi were Fusarium spp., Penicillium spp., Paecilomyces spp., and Aspergillus niger. Moreover, the density and trend of distribution of Fusaruim spp. in the indoor space was directivity to outdoor space by ventilation system. The present study has provided that incubation temperature had effect on airborne fungi remarkably. We are suggested that more studies would be conducted on incubation temperature and other ambient factors on airborne fungi.

Severe asthma in Japan

The characteristic phenotype of severe asthma in Japan seems to be distilled into the following two features: low incidence of obesity and high prevalence of patients with type 2 inflammation. Only 5-7% of Japanese severe asthma patients had a body mass index (BMI) ≥30 kg/m², and more than 80% of patients with severe asthma exhibited type 2 inflammation. Although the relationship between obesity and non-type 2 inflammation is complex, the low incidence of obesity might explain the prevalence of type 2 inflammation. Some asthma cohorts in Japan have investigated the roles of type 2 biomarkers extensively, including periostin, to identify a severe phenotype, suggesting the utility of combining biomarkers to identify an exacerbation-prone subgroup. Although the prevalence of severe asthma is comparable to Western countries, the rate of asthma death and disease burden seems to be lower in Japan. These trends might be due to the system of public health insurance for the whole nation, leading to good access to hospital and asthma specialists due to the geographically narrow country. In this review article, we will discuss the definition, epidemiology, comorbidities, biomarkers, specific phenotype, and current treatment for severe asthma in Japan.

Mold burden in house dust and its relationship with asthma control

OBJECTIVE

Some evidences indicate that exposure to molds or their products can be relevant for the loss of asthma control. Thus, we measured the mold burden present inside houses of subjects with asthma, and evaluated its relationship with asthma control.

METHODS

Markers of asthma control in adult patients residing in Mexico City were evaluated through questionnaires and spirometry. Dust was collected from the patients' houses and its fungal content was determined by mold specific quantitative PCR (MSQPCR) for 36 fungal species.

RESULTS

Forty-two patients with asthma (12 males, 30 females) with a mean age of 45 years (18-76 years) were included in the study. The level of asthma control measured through the Asthma Control Test ranged from 9 to 25 (mean 20.9). The FEV₁/FVC ratio fluctuated from 38 to 106 %predicted (mean, 87.4 %predicted). Associations between mold burden and asthma control differed between males and females. Thus, concentrations of some molds, particularly Aspergillus fumigatus, Aureobasidium pullulans, Stachybotrys chartarum, Alternaria alternata, Cladosporium cladosporioides 2, Cladosporium herbarum, and Epicoccum nigrum, were negatively associated with parameters of asthma control in male subjects, but not in female patients.

CONCLUSION

Our results showed that potential indoor exposure to some molds is associated with less asthma control in male subjects.

The sensitization pattern differs according to rhinitis and asthma multimorbidity in adults: the EGEA study

BACKGROUND

Mono- and polysensitization are different IgE-mediated allergic phenotypes in children. Allergic sensitization is associated with both allergic asthma and allergic rhinitis, however, associations between the sensitization pattern and particularly polysensitization with asthma and rhinitis remains poorly studied in adults.

AIM

The aim of this study was to assess how the allergic sensitization pattern associates with asthma, rhinitis and their multimorbidity.

METHODS

1199 adults from the EGEA study, with extensive phenotypic characterization and all data available on skin prick tests to 10 allergens, total IgE and blood eosinophils were included. Using questionnaires only, participants were classified into 6 groups: asymptomatic (no asthma, no rhinitis), non-allergic rhinitis alone, allergic rhinitis alone, asthma alone, asthma+non-allergic rhinitis and asthma+allergic rhinitis. Mono- and polysensitization were defined by a positive skin prick test to one or more than one allergen respectively.

RESULTS

Asymptomatic participants and those with non-allergic rhinitis alone were mostly non-sensitized (around 72%) while around 12% were polysensitized. Between 32% and 43% of participants with allergic rhinitis alone, asthma alone and asthma+non-allergic rhinitis were non-sensitized and between 37% and 46% of them were polysensitized. 65% of the participants with asthma+allergic rhinitis were polysensitized. The level of total IgE followed a similar trend to that of allergic sensitization. Eosinophils were increased in asthma, especially when associated with rhinitis. Nasal symptoms were more severe and eczema more common in participants with both asthma and allergic rhinitis than in the other groups.

CONCLUSIONS

Allergic sensitization and particularly polysensitization rates widely differ according to asthma and rhinitis status. This study emphasized the importance of taking into account multimorbidity between asthma and rhinitis and showed that allergic sensitization is not a dichotomic variable.

Fungal Sensitization Is Associated with Increased Risk of Life-Threatening Asthma

BACKGROUND

Fungal sensitization in patients with asthma has been associated with severe asthma and worse asthma outcomes.

OBJECTIVE

The purpose of this study was to determine the relationship between fungal and nonfungal sensitization, asthma severity, and clinical outcomes.

METHODS

A retrospective review of patients with asthma evaluated in an urban pulmonary subspecialty clinic in the United States was performed. Patients with fungal and nonfungal allergen sensitization were identified based on serum-specific immunoglobulin E (sIgE) testing. Demographic, clinical, laboratory, and spirometric data were obtained. The relationship between fungal sensitization and asthma outcomes was examined.

RESULTS

Of 390 patients with asthma identified, 307 had sIgE testing, of whom 53 (17.3%) had fungal sensitization, 117 (38.1%) had nonfungal sensitization, and 137 (44.6%) had no sensitization. Patients with fungal sensitization were more likely to be sensitized to ≥5 allergens than patients with nonfungal sensitization (66% for fungal vs 29% for nonfungal, P < .001). Serum IgE concentrations were highest in patients with fungal sensitization compared with patients with no sensitization or nonfungal sensitization (median, 825, 42, and 203 IU/mL, respectively, P < .001). Fungal sensitized patients were more likely to require intensive care unit (ICU) admission and mechanical ventilation than those with no sensitization or nonfungal sensitization (13.2%, 3.7%, and 3.4%, respectively, for ICU admission, P = .02; 11.3%, 1.5%, and 0.9%, respectively, for ventilation, P < .001).

CONCLUSIONS

Fungal sensitization is common in patients with asthma in an urban setting and is associated with greater sensitization to nonfungal allergens and increased risk of life-threatening asthma.