The Impact of Climate Change on the Sporulation of Atmospheric Fungi

The U.S. Global Change Research Program, Fourth National Climate Assessment reports that it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century. There are no convincing alternative explanations supported by observational evidence.

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 Clinical Implications of Aspergillus Fumigatus Sensitization in Difficult-To-Treat Asthma Patients

BACKGROUND

Fungal sensitivity has been associated with severe asthma outcomes. However, the clinical implication of Aspergillus fumigatus sensitization in difficult-to-treat (or difficult) asthma is unclear.

OBJECTIVES

To characterize the clinical implications of A fumigatus sensitization in a large difficult asthma cohort.

METHODS

Participants who underwent both skin prick and specific IgE testing to A fumigatus (n = 318) from the longitudinal real-life Wessex AsThma CoHort of difficult asthma, United Kingdom, were characterized by A fumigatus sensitization (either positive skin prick test result or specific IgE) and allergic bronchopulmonary aspergillosis status using clinical/pathophysiological disease measures.

RESULTS

A fumigatus sensitization was found in 23.9% (76 of 318) of patients with difficult asthma. Compared with A fumigatus nonsensitized subjects, those with sensitization were significantly more often male (50% vs 31%), older (58 years) with longer asthma duration (33 years), higher maintenance oral corticosteroid (39.7%) and asthma biologic use (27.6%), raised current/maximum log₁₀ total IgE+1 (2.43/2.72 IU/L), worse prebronchodilator airflow obstruction (FEV₁ 62.2% predicted, FEV₁/forced vital capacity 61.2%, forced expiratory flow between 25% and 75% exhalation 30.9% predicted), and frequent radiological bronchiectasis (40%), but had less psychophysiologic comorbidities. Allergic bronchopulmonary aspergillosis diagnosis was associated with higher treatment needs and stronger eosinophilic signals. Factors independently associated with A fumigatus sensitization in difficult asthma included maintenance oral corticosteroid use (odds ratio [OR], 3.34) and maximum log₁₀ total IgE+1 (OR, 4.30), whereas for allergic bronchopulmonary aspergillosis included maintenance oral corticosteroid use (OR, 6.98), maximum log₁₀ total IgE+1 (OR, 4.65), and radiological bronchiectasis (OR, 4.08).

CONCLUSIONS

A fumigatus sensitization in difficult asthma identifies a more severe form of airways disease associated with greater morbidity, treatment need, and airways dysfunction/damage, but fewer psychophysiologic comorbidities. Screening of A fumigatus status should be an early element in the comprehensive assessment of patients with difficult asthma.

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.

Diagnostic Cutoffs and Clinical Utility of Recombinant Aspergillus fumigatus Antigens in the Diagnosis of Allergic Bronchopulmonary Aspergillosis

BACKGROUND

The clinical utility of IgE against recombinant Aspergillus fumigatus (rAsp)-specific antigens in allergic bronchopulmonary aspergillosis (ABPA) remains unclear.

OBJECTIVE

To identify the optimal diagnostic cutoffs of rAsp-specific IgE in differentiating ABPA from A fumigatus-sensitized asthma (ASA), and define their utility in the diagnosis of ABPA.

METHODS

We enrolled consecutive subjects with ASA and ABPA. IgE against rAsp f1, f2, f3, f4, and f6 was assayed in all the subjects. We evaluated 3 fixed cutoffs (0.35, 0.5, and 1.0 kU_A/L) for their diagnostic performance in the entire cohort. We also divided the study population into derivation and validation cohorts. Cutoffs for rAsp-specific IgE were obtained using the receiver-operating characteristic analysis in the derivation cohort. We then evaluated the diagnostic performance of these cutoffs in the validation cohort. We further correlated rAsp-specific IgE levels in ABPA with asthma control, spirometry, imaging, and immunologic markers.

RESULTS

We included 194 subjects (123 ABPA and 71 ASA). The statistically derived cutoffs proved superior to fixed cutoffs. IgE against rAsp f1 yielded the best combination of sensitivity (89%) and specificity (100%). The sensitivity and specificity of IgE against either rAsp f1 (cutoff, 4.465 kU_A/L) or f2 (cutoff, 1.300 kU_A/L) for diagnosing ABPA were 100% and 81%, respectively. The correlation between rAsp-specific IgE and most clinical parameters of ABPA was weak.

CONCLUSIONS

IgE against rAsp f1 and f2 (using receiver-operating characteristic-derived cutoffs) were found to be the most useful in differentiating ABPA from ASA. Because this study was conducted at a single center, our results require further validation.