Aspergillus Bronchitis

Key points

  • Aspergillus bronchitis is a chronic infection of the large airways (bronchi) caused by Aspergillus fungi.

  • It usually occurs in people with damaged or abnormal airways, such as those with bronchiectasis or cystic fibrosis.

  • It is not an allergic condition like allergic bronchopulmonary aspergillosis (ABPA).

  • Symptoms often resemble a persistent chest infection that does not respond to antibiotics.

  • Diagnosis typically involves repeated detection of Aspergillus in sputum, compatible symptoms, and exclusion of other forms of aspergillosis.

  • Antifungal treatment can significantly improve symptoms in many patients.

What is Aspergillus bronchitis?

Aspergillus bronchitis is a chronic fungal infection of the bronchi, the larger airways that carry air into the lungs.

Aspergillus is a group of moulds that produce microscopic spores. These spores are present everywhere in the environment, particularly in:

  • soil and compost

  • damp buildings

  • decaying vegetation

  • dust

Most people breathe in Aspergillus spores daily without becoming ill because their lungs and immune system remove them efficiently.

However, in some individuals the fungus can persist in the airways and cause chronic infection, leading to Aspergillus bronchitis.

Where does Aspergillus bronchitis fit among Aspergillus diseases?

Aspergillus can cause several different lung diseases depending on a person’s immune system and lung health.

Disease Main mechanism Typical patients
Allergic bronchopulmonary aspergillosis (ABPA) Allergic immune reaction to Aspergillus Asthma, cystic fibrosis
Aspergillus bronchitis Chronic infection of the bronchi Bronchiectasis, airway disease
Chronic pulmonary aspergillosis (CPA) Progressive lung infection with cavities COPD, prior TB, lung damage
Invasive aspergillosis Aggressive infection spreading through tissues Severely immunocompromised

Aspergillus bronchitis often occurs between colonisation and invasive infection — the fungus is actively causing symptoms but has not invaded lung tissue deeply.

Who is at risk?

Aspergillus bronchitis most commonly occurs in people who already have structural lung disease, including:

  • Bronchiectasis

  • Cystic fibrosis

  • Severe COPD

  • Chronic airway inflammation

It may also occur in people with mild immune suppression, for example from:

  • inhaled corticosteroids

  • oral corticosteroids

  • certain immune-modifying medications

  • advanced age

Exposure to large numbers of spores — for example during gardening or in mould-contaminated buildings — may also increase risk.

Importantly, Aspergillus bronchitis is not contagious and cannot be passed from one person to another.

Symptoms

Symptoms are usually chronic and persistent, and may resemble a long-lasting chest infection.

Common symptoms include:

  • Persistent cough

  • Production of sputum (phlegm)

  • Thick or sticky mucus

  • Increased sputum volume

  • Breathlessness

  • Wheezing

  • Recurrent “chest infections” that do not improve with antibiotics

Some patients notice brown plugs of mucus or worsening bronchiectasis symptoms.

Symptoms often continue for months before diagnosis.

How is Aspergillus bronchitis diagnosed?

Diagnosis can be challenging because Aspergillus can sometimes be present in sputum without causing disease. Doctors therefore combine several pieces of information.

Typical diagnostic features include:

Clinical features

  • Chronic lower airway symptoms lasting more than 4 weeks

  • Symptoms not improving with antibiotics

Microbiology

  • Repeated detection of Aspergillus in sputum cultures or PCR

Blood tests

Supportive findings may include:

  • Elevated Aspergillus IgG antibodies

  • Usually normal or only mildly raised IgE levels (unlike ABPA)

Imaging

Chest CT scans usually show:

  • underlying bronchiectasis

  • airway inflammation

  • mucus plugging

But they do not show lung cavities, which are typical of chronic pulmonary aspergillosis.

Bronchoscopy (occasionally)

In some cases a bronchoscopy may reveal:

  • fungal plaques lining the bronchi

  • thick mucus plugs containing fungal material

Response to treatment

A clear improvement with antifungal therapy also supports the diagnosis.

Treatment

The main treatment for Aspergillus bronchitis is oral antifungal medication.

Antifungal therapy

The most commonly used medication is:

  • Itraconazole

Other antifungal drugs may be used if itraconazole is not suitable, such as:

  • voriconazole

  • posaconazole

Treatment often continues for several months depending on response.

Patients frequently notice improvement in symptoms within 4–8 weeks, particularly:

  • reduced cough

  • less sputum

  • improved breathing

Monitoring treatment

Antifungal medicines require monitoring to ensure they are safe and effective.

Doctors may arrange:

  • blood tests to check drug levels

  • liver function tests

  • review of drug interactions

Itraconazole can interact with many medications, so clinicians usually review all current treatments before starting therapy.

Airway clearance

People with bronchiectasis or chronic mucus production benefit from:

  • physiotherapy techniques to clear mucus

  • breathing exercises

  • airway clearance devices

These help remove mucus where fungi can grow.

Managing underlying lung disease

Treatment of other lung conditions remains important, including:

  • bronchiectasis management

  • inhaler treatment for asthma or COPD

  • vaccination against respiratory infections

Common questions

Is Aspergillus bronchitis the same as ABPA?

No.
ABPA is an allergic reaction to Aspergillus, whereas Aspergillus bronchitis is a chronic infection of the airways.

The treatments and immune mechanisms are different.

Is Aspergillus bronchitis the same as colonisation?

Not exactly.

Sometimes Aspergillus can be present in sputum without causing disease, which is called colonisation.

In Aspergillus bronchitis:

  • the fungus is actively contributing to symptoms

  • antifungal treatment often improves the condition.

Can Aspergillus bronchitis turn into chronic pulmonary aspergillosis?

Usually not.

However, both conditions occur in people with damaged lungs, so occasionally patients may develop more than one form of aspergillosis over time.

Regular follow-up helps monitor for this.

Do patients always need antifungal treatment?

Not always.

Doctors may consider treatment if:

  • symptoms are significant

  • Aspergillus is repeatedly detected

  • other causes have been excluded

Treatment decisions are often individualised.

When to seek medical advice

You should speak to your doctor if you have:

  • a chronic cough lasting more than 4–8 weeks

  • repeated chest infections that do not improve with antibiotics

  • bronchiectasis with worsening sputum production

  • persistent fungal growth reported in sputum cultures

Early diagnosis can help prevent long periods of untreated symptoms.

References

  1. Chotirmall SH, Al-Alawi M, Mirkovic B, Lavelle G, Logan PM, Greene CM, McElvaney NG. Aspergillus-associated airway disease, inflammation, and the innate immune response. Biomed Res Int. 2013;2013:723129. doi: 10.1155/2013/723129. Epub 2013 Jul 21. PMID: 23971044; PMCID: PMC3736487.

  2. Denning DW. Chronic forms of pulmonary aspergillosis. Clin Microbiol Infect. 2001;7 Suppl 2:25-31. doi: 10.1111/j.1469-0691.2001.tb00006.x. PMID: 11525215.

Author and review information

Author: National Aspergillosis Centre team
Audience: Patients, carers, and non-specialist clinicians
Last reviewed: March 2026