Prospective observational study of respiratory Aspergillus colonization or disease in patients with various stages of chronic obstructive pulmonary disease utilizing culture versus nonculture techniques

Infection, Allergy, and Inflammation: The Role of Aspergillus fumigatus in Cystic Fibrosis

Aspergillus fumigatus (Af) is a mold frequently detected in airway samples from people with cystic fibrosis (pwCF). Abnormal airway mucus may allow Af to germinate, resulting in airway infection or an allergic response. While Af is known to increase morbidity in pwCF, individual responses and the degree of impact on lung disease vary. Improved approaches to diagnosis, treatment, and prevention of Af, particularly the persistent Af infection, are needed. This update highlights our current understanding of Af pathophysiology in the CF airway, the effects of Af on pwCF, and areas of research needed to improve clinical outcomes.

The clinical spectrum of aspergillosis in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. In this review, we present the clinical spectrum and pathogenesis of syndromes caused by Aspergillus in COPD namely invasive aspergillosis (IA), community-acquired Aspergillus pneumonia, chronic pulmonary Aspergillosis and Aspergillus sensitisation. Some of these entities are clearly linked to COPD, while others may coexist, but are less clearly liked directly to COPD. We discuss current uncertainties as these pertain to IA in COPD cohorts and explore areas for future research in this field.

Invasive Pulmonary Aspergillosis in Patients with and without SARS-CoV-2 Infection

The recent European Confederation of Medical Mycology (ECMM) and the International Society for Human and Animal Mycology (ISHAM) 2020 consensus classification proposes criteria to define coronavirus 2019 (COVID-19)-associated invasive pulmonary aspergillosis (CAPA), including mycological evidence obtained via non-bronchoscopic lavage. Given the low specificity of radiological findings in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, this criterion makes it difficult to differentiate between invasive pulmonary aspergillosis (IPA) and colonization. This unicenter and retrospective study includes 240 patients with isolates of any Aspergillus species in any respiratory samples during a 20-month study (140 IPA and 100 colonization). Mortality was high in the IPA and colonization groups (37.1% and 34.0%, respectively; p = 0.61), especially in patients with SARS-CoV-2 infection, where mortality was higher in colonized patients (40.7% vs. 66.6.%; p: 0.021). Multivariate analysis confirmed the following variables to be independently associated with increased mortality: age > 65 years, acute or chronic renal failure at diagnosis, thrombocytopenia (<100,000 platelets/µL) at admission, inotrope requirement, and SARS-CoV-2 infection, but not the presence of IPA. This series shows that the isolation of Aspergillus spp. in respiratory samples, whether associated with disease criteria or not, is associated with high mortality, especially in patients with SARS-CoV-2 infection, and suggests an early initiation of treatment given its high mortality rate.

Impact of Lung Microbiota on COPD

There is a fine balance in maintaining healthy microbiota composition, and its alterations due to genetic, lifestyle, and environmental factors can lead to the onset of respiratory dysfunctions such as chronic obstructive pulmonary disease (COPD). The relationship between lung microbiota and COPD is currently under study. Little is known about the role of the microbiota in patients with stable or exacerbated COPD. Inflammation in COPD disorders appears to be characterised by dysbiosis, reduced lung activity, and an imbalance between the innate and adaptive immune systems. Lung microbiota intervention could ameliorate these disorders. The microbiota’s anti-inflammatory action could be decisive in the onset of pathologies. In this review, we highlight the feedback loop between microbiota dysfunction, immune response, inflammation, and lung damage in relation to COPD status in order to encourage the development of innovative therapeutic goals for the prevention and management of this disease.

de la Pedrosa E, López-Campos JL, Máiz L, del Campo R, Martínez-García MÁ. The Human Mycobiome in Chronic Respiratory Diseases: Current Situation and Future Perspectives

Microbes play an important role in the pathogenesis of chronic lung diseases, such as chronic obstructive pulmonary disease, cystic fibrosis, non-cystic fibrosis bronchiectasis, and asthma. While the role of bacterial pathogens has been extensively studied, the contribution of fungal species to the pathogenesis of chronic lung diseases is much less understood. The recent introduction of next-generation sequencing techniques has revealed the existence of complex microbial lung communities in healthy individuals and patients with chronic respiratory disorders, with fungi being an important part of these communities' structure (mycobiome). There is growing evidence that the components of the lung mycobiome influence the clinical course of chronic respiratory diseases, not only by direct pathogenesis but also by interacting with bacterial species and with the host's physiology. In this article, we review the current knowledge on the role of fungi in chronic respiratory diseases, which was obtained by conventional culture and next-generation sequencing, highlighting the limitations of both techniques and exploring future research areas.

Pulmonary aspergillosis and cryptococcosis as a complication of COVID-19

Invasive fungal infections may complicate infection by SARS-CoV-2 and increase morbidity and mortality. A 59-year-old man with multiple medical comorbidities was transferred to our hospital for worsening hypoxic respiratory failure due to COVID-19 and received high-dose corticosteroids and 2 doses of cyclophosphamide. He was diagnosed with pulmonary aspergillosis and cryptococcosis by culture of a bronchoalveolar lavage sample. This patient's secondary infections were likely due to treatment with immunosuppressants, his comorbidities, and his prolonged critical illness.

HIGH FREQUENCY OF ALLERGIC BRONCHOPULMONARY ASPERGILLOSIS IN BRONCHIECTASIS-COPD OVERLAP

BACKGROUND

Allergic bronchopulmonary aspergillosis (ABPA) is associated with frequent exacerbations and poor outcomes in chronic respiratory disease but remains underdiagnosed. The role of fungal sensitization in bronchiectasis-COPD overlap (BCO) is unknown.

RESEARCH QUESTION

What is the occurrence and clinical relevance of Aspergillus sensitization and ABPA in BCO when compared to individuals with COPD or bronchiectasis without overlap?

STUDY DESIGN

Prospective, observational and cross-sectional.

METHODS

We prospectively recruited n=280 patients during periods of clinical stability with bronchiectasis (n=183), COPD (n=50) and BCO (n=47) from six hospitals across three countries (Singapore, Malaysia, and Scotland). We assessed sensitization responses (as specific IgE) to a panel of recombinant Aspergillus fumigatus (rAsp f) allergens and the occurrence of ABPA (ABPA) in relation to clinical outcomes.

RESULTS

Individuals with BCO illustrate an increased frequency and clinical severity of ABPA compared to COPD and bronchiectasis without overlap. BCO-associated ABPA demonstrates more severe disease, higher exacerbation rates and lower lung function when compared to ABPA occurring in the absence of overlap. BCO with a severe bronchiectasis severity index (BSI) (>9) significantly associates with the occurrence of ABPA that is unrelated to underlying COPD severity.

CONCLUSIONS

BCO demonstrates a high frequency of ABPA that associates with a severe BSI (>9) and poor clinical outcomes. Clinicians should maintain a high index of suspicion for the potential development of ABPA in BCO patients with high BSI.

Increased Incidence and Associated Risk Factors of Aspergillosis in Patients with Bronchiectasis

There are insufficient data regarding the relationship between non-cystic fibrosis bronchiectasis and incident aspergillosis. We performed a population-based, matched cohort study using data from the Korean National Health Insurance database between 2003 and 2013. The incidence of aspergillosis was 50/100,000 person-years in the bronchiectasis cohort and 11/100,000 person-years in the matched cohort (subdistribution hazard ratio, 4.53; 95% confidence interval (CI), 3.25–6.32). Among the bronchiectasis cohort, chronic obstructive pulmonary disease (adjusted HR, 1.95; 95% CI, 1.07–3.57), previous pulmonary tuberculosis (adjusted HR, 3.67; 95% CI, 2.03–6.64), and non-tuberculous mycobacterial pulmonary disease (adjusted HR, 11.25; 95% CI, 1.49–85.18) increased the risk of incident aspergillosis. The incidence of aspergillosis in patients with bronchiectasis was approximately 4.5-fold that in those without bronchiectasis. Comorbid pulmonary diseases—chronic obstructive pulmonary disease, previous pulmonary tuberculosis, and non-tuberculous mycobacterial pulmonary disease—significantly increased the risk of aspergillosis in patients with bronchiectasis. Our study indicates that close monitoring is warranted for aspergillosis in patients with bronchiectasis.

Respiratory Mycoses in COPD and Bronchiectasis

Chronic obstructive pulmonary disease (COPD) and bronchiectasis represent chronic airway diseases associated with significant morbidity and mortality. Bacteria and viruses are commonly implicated in acute exacerbations; however the significance of fungi in these airways remains poorly defined. While COPD and bronchiectasis remain recognized risk factors for the occurrence of Aspergillus-associated disease including chronic and invasive aspergillosis, underlying mechanisms that lead to the progression from colonization to invasive disease remain uncertain. Nonetheless, advances in molecular technologies have improved our detection, identification and understanding of resident fungi characterizing these airways. Mycobiome sequencing has revealed the complex varied and myriad profile of airway fungi in COPD and bronchiectasis, including their association with disease presentation, progression, and mortality. In this review, we outline the emerging evidence for the clinical importance of fungi in COPD and bronchiectasis, available diagnostic modalities, mycobiome sequencing approaches and association with clinical outcomes.