Aspergillus and bronchiectasis: understanding risks to improve outcomes

New research has explored how a common environmental fungus called Aspergillus affects people with bronchiectasis. The findings show that some people have an allergic reaction to Aspergillus, which can make their lung problems worse and breathing more difficult. This can also increase the likelihood of flare-ups, where symptoms worsen over a period of time.

Background 

Bronchiectasis is a long-term lung condition where the airways become damaged, unusually wide and blocked with thick, sticky mucus that can be difficult to clear from the airways. This can lead to a persistent cough and frequent chest infections that make breathing more difficult.  

Aspergillus is a type of fungus found in the environment, and it can affect people with bronchiectasis in different ways: 

• Some people develop a condition called Allergic Bronchopulmonary Aspergillosis (ABPA), caused by an allergic reaction to Aspergillus. 

• Others have a milder allergic reaction, known as Aspergillus sensitisation (AS), where their body becomes sensitive to the fungus, but they do not develop ABPA.  

• Some people show signs of past or current exposure through higher-than-normal levels of antibodies that specifically target Aspergillus within their blood. Antibodies are substances made by the immune system to help fight off infections. When antibody levels are higher than normal, it can signal that the body is reacting to something harmful in a way that could make lung problems worse. 

 Until now, it has not been clear how these conditions affect people with bronchiectasis.

What did the study find?  

This study looked at data from almost 10,000 patients with bronchiectasis to understand how many patients showed signs of Aspergillus-related conditions based on markers in their blood and how these conditions affect their health. The data was collected from patients in countries around the world between 2015 and 2022. The key findings include: 

• Around 1 in 16 people had ABPA, a condition driven by an allergic reaction towards Aspergillus. 

• About 1 in 17 had AS, meaning they showed signs of an allergic immune response towards Aspergillus, but not strongly enough to cause ABPA. 

• 1 in 12 had raised Aspergillus-specific antibodies in their blood, suggesting past or ongoing exposure to the fungus. 

• A smaller group had both AS and raised antibody levels. 

• Most patients showed no signs of Aspergillus-related disease.  

People with ABPA, AS or raised Aspergillus-specific antibodies tended to have worse symptoms, reduced lung function and more frequent flare-ups. Those with raised antibody levels were more likely to experience a higher amount of serious chest infections needing hospital treatment. People with AS, who were not using inhaled steroid treatments, were also more likely to have flare-ups and need hospital care.

Why is this important? 

This research shows that Aspergillus-related lung disease is common in people with bronchiectasis and can make their symptoms worse. The study suggests ways to improve diagnosis and treatment, including: 

• Better testing so more people are checked for Aspergillus-related conditions and get the right diagnosis and treatment sooner. 

• Developing clinical trials to test whether inhaled steroids help people with AS and lower their risk of flare-ups. 

• Exploring antifungal treatments for people with high Aspergillus antibody levels, as these medicines may help treat serious Aspergillus infections. 
• Developing better long-term support to help people with bronchiectasis and Aspergillus-related conditions manage their health.

This paper is part of the European Bronchiectasis Registry’s efforts to improve research and treatment for people with long-term lung conditions. The Registry was created by EMBARC, the European Multicentre Bronchiectasis Audit and Research Collaboration, which was established in 2012 to facilitate multidisciplinary collaborative research in non-CF bronchiectasis.  

Read the full paper: Aspergillus Serologic Findings and Clinical Outcomes in Patients with Bronchiectasis. CHEST, 2024.