Asthma and Aspergillosis

How fungal spores interact with asthma and other lung diseases

Every day we inhale thousands of microscopic fungal spores from the environment. One of the most common fungi in the air is Aspergillus fumigatus. In healthy lungs these spores are removed quickly by the lungs’ natural defence systems and cause no illness.

However, in people with asthma—particularly severe asthma—the interaction between the lungs and Aspergillus can be very different. The fungus may trigger allergic inflammation, grow in mucus within the airways, or occasionally contribute to chronic lung disease.

Understanding this relationship helps explain several important conditions including:

Aspergillus sensitisation
Severe Asthma with Fungal Sensitisation (SAFS)
Allergic Bronchopulmonary Aspergillosis (ABPA)
Aspergillus bronchitis
Chronic Pulmonary Aspergillosis (CPA)

Although asthma is the most common condition linked to Aspergillus allergy, other lung diseases such as bronchiectasis, Chronic Obstructive Pulmonary Disease (COPD), and tuberculosis-related lung damage can also create environments where the fungus becomes important.

Why Asthma Creates a Favourable Environment for Aspergillus

Asthma is a disease of airway inflammation and hyper-reactivity. The bronchi narrow during attacks because the airway wall becomes swollen and the surrounding smooth muscle contracts.

Several features of asthma make it easier for Aspergillus spores to remain in the lungs.

Mucus production

Asthma often causes increased production of thick airway mucus.

Normally mucus traps inhaled particles and moves them upward toward the throat via the mucociliary escalator.

In asthma:

mucus becomes thicker
clearance becomes less efficient
spores remain trapped

This trapped environment allows fungal spores to persist in the airway mucus.

Allergic immune responses

Many asthma patients have Type-2 (T2) inflammation (50-70%), involving immune pathways driven by:

Immunoglobulin E (IgE)
Interleukin-4
Interleukin-5
Interleukin-13
eosinophils

These pathways respond strongly to fungal allergens. When the immune system recognises Aspergillus proteins it may trigger allergic inflammation in the airways.

Fungal sensitisation is increasingly recognised as an important contributor to severe asthma (PMID: 24735832).

Aspergillus Sensitisation

Many people with asthma develop allergic sensitisation to Aspergillus.

Sensitisation means the immune system produces antibodies against fungal proteins.

Features include:

positive Aspergillus skin test or IgE blood test
worsening asthma symptoms
increased exacerbations

Studies suggest 10–25% of patients attending severe asthma clinics show Aspergillus sensitisation (PMID: 24735832).

However, sensitisation alone does not necessarily cause lung damage.

Severe Asthma with Fungal Sensitisation (SAFS)

Some patients with severe asthma have fungal sensitisation but do not meet the criteria for ABPA.

This condition is known as Severe Asthma with Fungal Sensitisation (SAFS).

Typical features include:

severe or poorly controlled asthma
fungal allergy
moderate IgE elevation

A randomised controlled trial demonstrated that antifungal therapy may improve symptoms in some SAFS patients (PMID: 18948425).

Allergic Bronchopulmonary Aspergillosis (ABPA)

Allergic Bronchopulmonary Aspergillosis is the most important Aspergillus-related disease associated with asthma.

ABPA occurs when Aspergillus grows within airway mucus and triggers a strong allergic immune response.

Typical findings include:

very high total IgE levels
Aspergillus-specific IgE and IgG antibodies
eosinophilia
mucus plugs containing fungal hyphae
central bronchiectasis

ABPA occurs in approximately:

1–2% of all asthma patients
up to 10–15% of severe asthma patients

These figures come from global prevalence estimates of ABPA in asthma populations (PMID: 23210682/.

Modern diagnostic criteria for ABPA were updated by the International Society for Human and Animal Mycology (ISHAM) in 2024 (PMID: 38423624).

Asthma and Aspergillus Disease Pathway

Possible interactions between asthma and Aspergillus. Some patients develop allergic disease (ABPA) which may lead to airway damage such as bronchiectasis (NB Progression to CPA is very rare).

When ABPA Causes Bronchiectasis

Repeated inflammation from ABPA may damage airway walls and lead to bronchiectasis.

Bronchiectasis occurs when airways become:

permanently widened
distorted
unable to clear mucus effectively

Instead of being cleared from the lungs, mucus pools in the airways.

This retained mucus creates an environment where microorganisms—including fungi—can grow.

Aspergillus Bronchitis

In some patients with bronchiectasis or chronic lung disease, Aspergillus may persist in airway mucus and cause chronic airway infection rather than allergy.

Symptoms may include:

chronic cough
sputum production
repeated positive Aspergillus cultures

IgE levels are usually lower than in ABPA.

Chronic Pulmonary Aspergillosis (CPA)

Chronic Pulmonary Aspergillosis is a slowly progressive fungal infection of damaged lung tissue.

CPA usually develops in lungs containing:

cavities
severe structural damage

Common underlying diseases include:

tuberculosis
sarcoidosis
severe COPD

Globally, the most common cause of CPA is previous tuberculosis infection (PMID: 22271943).

Asthma alone rarely causes CPA, but severe bronchiectasis or ABPA-related lung damage may occasionally lead to it.

Aspergillosis and Immune Competence

Different forms of aspergillosis occur depending on lung damage and immune function.

Key Messages

Asthma is one of the most important diseases associated with Aspergillus-related lung conditions.
Many asthma patients develop fungal sensitisation.
A smaller proportion develop Allergic Bronchopulmonary Aspergillosis (ABPA).
Repeated inflammation from ABPA can lead to bronchiectasis.
Chronic pulmonary aspergillosis is rare in asthma alone but may occur if significant lung damage develops.

Understanding these interactions helps guide diagnosis and treatment for people living with asthma and Aspergillus-related disease.

Looking further into the future - could we control lung damage, preserve healthy lung tissue better?

Can Lungs Repair Themselves?

What New Research Means for People with CPA (and Other Aspergillosis)

A recent scientific discovery has helped researchers understand how certain lung cells decide whether to focus on repairing damage or defending against infection. The work, highlighted by the Mayo Clinic and published in Nature Communications, describes a molecular “switch” inside specialised lung cells that influences this balance.

For people living with Chronic Pulmonary Aspergillosis (CPA) — and also those with Allergic Bronchopulmonary Aspergillosis (ABPA) — this kind of research is relevant. But it needs careful explanation.

This is not about rebuilding destroyed lungs.
It is about understanding how to better protect and preserve the lung tissue that remains.

The Discovery: A “Repair vs Defence” Switch

Researchers identified a regulatory circuit in alveolar type II (AT2) cells — specialised cells that:

Produce surfactant (which keeps air sacs open)
Act as a reserve “repair” population in the lung
Can regenerate other essential lung cells after injury

The study showed that these cells operate under tight control. When infection is present, they prioritise defence. When injury needs healing, they can switch into repair mode.

The key insight is that this switch is biologically regulated. It is not random. That means, in theory, it may one day be possible to influence it.

What “Repair” Means — and What It Does Not Mean

When we talk about lung repair in this context, we must be very clear.

It does not mean:

Lung cavities caused by CPA will close in the foreseeable future
Established fibrosis will melt away
Bronchiectasis will reverse
Severely distorted lung architecture will rebuild

CPA cavities represent major structural remodelling — destruction of alveoli, scarring, altered blood supply, and thickened pleura. Reconstructing that complex architecture is biologically extremely challenging and not currently realistic within the next decade.

What repair does realistically mean

In chronic lung disease, “repair” is more likely to mean:

Supporting survival of remaining alveoli
Preventing excessive fibrotic signalling
Helping lung lining cells recover more efficiently after inflammation
Reducing cumulative injury from repeated infection
Slowing progression of structural change

In other words:

Not rebuilding what is gone — but better protecting what remains.

For many people with CPA, this is a crucial distinction.

Why Preservation Is a Major Goal in CPA

CPA usually develops in lungs already weakened by conditions such as tuberculosis, non-tuberculous mycobacteria, chronic obstructive pulmonary disease, or severe pneumonia.

Over time, CPA can lead to:

Expanding cavities
Progressive scarring
Reduced gas exchange
Reduced exercise tolerance

Many patients have limited lung reserve. Even small additional losses of functioning lung tissue can significantly increase breathlessness or fatigue.

If future therapies could slow the rate of progression — even modestly — that would meaningfully affect long-term outcomes.

Flattening the decline curve is not trivial. It changes quality of life.

Why This Also Matters in ABPA

In ABPA, repeated inflammatory episodes can lead to:

Airway remodelling
Mucus plugging
Development or progression of bronchiectasis

Better control of inflammatory signalling — combined with improved epithelial recovery — could reduce long-term airway damage.

Again, this is about preservation rather than reversal.

Where Development Has Reached

The current research is still laboratory-based. It used advanced techniques such as:

Single-cell sequencing
Imaging of lung tissue
Preclinical models of injury

No human treatments based on this discovery are yet available.

However, the significance lies in identifying:

A defined molecular pathway
A controllable regulatory mechanism
A clearer understanding of why repair fails in chronic inflammation

That foundational knowledge is what eventually allows targeted drug development.

The Balance Challenge in Aspergillosis

There is an additional complexity in fungal lung disease.

Any attempt to promote repair must not weaken antifungal defence.

The immune system must:

Control Aspergillus
Avoid causing excessive inflammatory damage

Future therapies would need to strike that balance carefully.

What This Means for Patients Now

This discovery does not change current treatment.

The most effective preservation strategies today remain:

Consistent antifungal therapy when indicated
Careful inflammatory control
Biologic therapies where appropriate
Airway clearance
Vaccination and infection prevention
Avoiding damp and mould exposure
Pulmonary rehabilitation

These measures are already forms of lung preservation.

A Realistic and Hopeful Perspective

It is unlikely that cavities from CPA will be repaired in the near future.

It is realistic that within the next 5–10 years we may see improved strategies aimed at:

Slowing structural progression
Supporting endogenous repair cells
Reducing fibrotic signalling
Improving recovery after exacerbations

For people living long-term with CPA or ABPA, even incremental preservation could significantly affect independence and quality of life.

The science is still early — but understanding how the lung decides to repair itself is an important step forward.

Reference

Sawhney, A.S., Deskin, B.J., Cai, J. et al. A molecular circuit regulates fate plasticity in emerging and adult AT2 cells. Nat Commun 16, 8924 (2025). https://doi.org/10.1038/s41467-025-64224-1

by GAtherton

🧬 Could Antibody-Driven Dissolving of Charcot–Leyden Crystals Help ABPA?

Researchers have recently discovered that Charcot–Leyden crystals (CLCs) — the needle-shaped structures formed from the eosinophil protein galectin-10 — are not just debris.

In laboratory studies, specially designed antibodies can dissolve these crystals.

This has raised two important questions:

Could dissolving the crystals reduce airway inflammation?
Could dissolving them make mucus plugs easier to clear?

Here is what we currently know.

1️⃣ Could dissolving crystals reduce airway inflammation?

What we know

Laboratory and animal studies have shown:

Charcot–Leyden crystals can activate immune cells (especially macrophages).
They can stimulate inflammatory pathways (including inflammasome signalling).
In mouse models, antibodies targeting galectin-10 dissolved the crystals.
When crystals were dissolved, airway inflammation decreased.

This suggests that the crystals themselves may amplify inflammation, rather than simply mark it.

What this means biologically

In ABPA and eosinophilic asthma:

Eosinophils release galectin-10.
Galectin-10 crystallises.
Crystals may trigger further immune activation.
That leads to more inflammation → more eosinophils → more crystals.

Dissolving the crystals could theoretically interrupt this feedback loop.

How likely is this to help inflammation in humans?

Moderately plausible, but not yet proven.

The biological mechanism is strong.
The animal data are encouraging.
But no human clinical trials have yet shown reduced inflammation through crystal dissolution.

If developed successfully, this approach could:

Reduce airway immune activation
Lower exacerbation risk
Potentially reduce steroid dependence

But at present, it remains investigational.

2️⃣ Could dissolving crystals make mucus plugs easier to cough up?

This is more speculative — but still biologically reasonable.

Why mucus plugs are so thick in ABPA

ABPA mucus plugs contain:

Gel-forming mucins
DNA from inflammatory cells
Dead cells
Fungal fragments
Eosinophil proteins
Charcot–Leyden crystals

The crystals are:

Rigid
Needle-shaped
Structurally stable

When embedded in mucus, they likely increase:

Mechanical stiffness
Plug density
Resistance to deformation

From a physics perspective:

Removing rigid crystalline structures from a gel should reduce stiffness and improve flow.

Do we have direct evidence?

No.

There are currently:

No human studies measuring mucus clearance after crystal dissolution
No trials showing improved plug expectoration from crystal-targeting therapy

So while it is plausible that dissolving crystals could soften plugs, this has not yet been demonstrated in patients.

3️⃣ How strong is the overall case?

Outcome	Evidence strength	Likelihood
Reduced inflammation	Strong biological rationale + animal data	Moderately promising
Easier mucus clearance	Biophysical plausibility only	Possible but unproven

Inflammation reduction is the more evidence-supported target.
Improved plug clearance is plausible but currently theoretical.

4️⃣ How does this compare to existing treatments?

Current therapies (e.g., anti-IL-5 biologics) reduce eosinophils upstream.

That leads to:

Less galectin-10 release
Fewer crystals forming
Reduced inflammation
Often improved mucus plugging

So biologics already indirectly reduce crystal burden.

A crystal-dissolving antibody would act downstream, targeting the structural product directly.

This could theoretically:

Accelerate resolution of existing plugs
Reduce residual inflammatory signalling

But again, this remains in early research stages.

5️⃣ Practical take-home message

At present:

Dissolving Charcot–Leyden crystals reduces inflammation in animal models.
It is biologically plausible that this could also soften mucus plugs.
There is no human clinical proof yet.
No approved therapy currently targets the crystals directly.

The concept is scientifically credible — but still under development.

🔭 The Bigger Picture

ABPA is increasingly understood as a condition driven by:

Eosinophils
Allergic immune signalling
Abnormal mucus biology
Structural plug formation

Crystal-targeting therapies may eventually become part of a more precise approach to treating eosinophilic airway disease.

But for now, they remain a promising research direction rather than a clinical option.

by GAtherton

🔬 Charcot–Leyden Crystals in ABPA and Asthma

What are they? Why do they form? Do they matter?

If you live with Allergic Bronchopulmonary Aspergillosis (ABPA) or severe asthma, you may see the term Charcot–Leyden crystals in a sputum or pathology report.

They can sound worrying.

They are:

Not fungus
Not infection
Not cancer

They are a sign of a particular type of allergic inflammation in the airways.

🧬 What Are Charcot–Leyden Crystals?

Charcot–Leyden crystals are microscopic, needle-shaped structures found in mucus.

They are made from a protein called galectin-10, which is stored inside a type of white blood cell called an eosinophil.

Eosinophils are immune cells involved in:

Allergic asthma
ABPA
Severe asthma with fungal sensitisation
Parasitic infections

When eosinophils are activated and break down, they release galectin-10.
If enough of this protein accumulates in thick airway mucus, it crystallises into visible crystals.

So the crystals are made from your immune cells, not from Aspergillus.

🫁 Why Do They Appear in ABPA?

In ABPA:

The immune system overreacts to Aspergillus fumigatus.
This triggers a strong allergic (Type 2) immune response.
Large numbers of eosinophils move into the airways.
Eosinophils break down and release galectin-10.
The protein crystallises inside mucus plugs.

The crystals are therefore a footprint of intense allergic inflammation, not fungal invasion.

🌡 Is Most ABPA Eosinophilic?

Yes — almost all classical ABPA is eosinophilic.

ABPA is fundamentally a Type 2 allergic condition, driven by immune pathways involving:

IL-4
IL-5
IL-13
IgE
Eosinophils

IL-5 in particular stimulates eosinophil production and survival.
Because of this, eosinophils are central to the disease process.

Historically, raised blood eosinophils have been part of diagnostic criteria.

However:

Eosinophil counts can fluctuate
Steroids can suppress blood levels
Eosinophils may still be present in airway mucus even if blood counts appear normal

So ABPA is biologically eosinophilic — even if a single blood test does not show a high count.

True non-eosinophilic ABPA would be unusual and would prompt clinicians to reconsider the diagnosis.

❓ Are Crystals Caused by Aspergillus Infection?

No.

They are caused by the immune reaction to Aspergillus — not by the fungus itself.

They can also be seen in:

Severe eosinophilic asthma
Parasitic infections
Other allergic lung conditions

They reflect eosinophil activity, not fungal growth.

🧠 Why Don’t All People with Asthma Develop These Crystals?

Asthma is not one single disease. It has different inflammatory patterns.

Type 2 (Eosinophilic) Asthma

This involves high eosinophils and allergic pathways.

Common in:

Allergic asthma
ABPA
Severe eosinophilic asthma

These patients can develop Charcot–Leyden crystals.

Non–Type 2 (Non-Eosinophilic) Asthma

This includes:

Neutrophilic asthma

Driven by neutrophils rather than eosinophils.

Paucigranulocytic asthma

Very few inflammatory cells present.

In these forms:

Eosinophils are low
Galectin-10 is not released in large amounts
Crystals are unlikely to form

🧱 Do Charcot–Leyden Crystals Make Mucus Plugs Worse?

Possibly.

Research suggests they may:

Increase mucus thickness
Contribute mechanically to airway blockage
Stimulate further inflammation

For many years they were thought to be harmless debris.
Modern studies suggest they may actively amplify inflammation when present in large amounts.

🎯 Do They Have a Purpose?

Eosinophils evolved mainly to help fight parasitic infections.

Galectin-10 probably has immune signalling roles inside cells.

However, when large amounts are released into thick airway mucus, crystallisation appears to be a by-product of excessive immune activity rather than a useful defence.

In ABPA and allergic asthma, they are more likely part of the problem than part of the solution.

💧 Can Their Formation Be Reduced?

Hydration alone does not stop them forming.

Drinking fluids helps:

Keep mucus less sticky
Support airway clearance

But it does not prevent eosinophils releasing galectin-10.

What reduces crystal formation?

Reducing eosinophilic inflammation:

Corticosteroids
Anti-IL-5 biologics
Anti-IL-4/IL-13 biologics

When eosinophil numbers fall:

→ Less galectin-10 is released
→ Fewer crystals form

Antifungal treatment in ABPA may indirectly help by reducing allergic stimulation, but the main driver is the immune response.

📊 Do They Change Treatment?

Not directly.

Doctors base treatment on:

Symptoms
Blood eosinophils
Total IgE
Imaging
Lung function
Exacerbation history

Crystals support the diagnosis of eosinophilic inflammation but do not determine treatment alone.

🔎 What Do They Tell Us?

Charcot–Leyden crystals tell us:

The airway inflammation is eosinophilic.
The immune response is strongly allergic.
Mucus plugging risk may be higher.

They are a marker of immune overreaction, not infection severity.

🧠 Key Points to Remember

They are made from proteins released by eosinophils.
They are not Aspergillus.
They do not mean invasive fungal infection.
Most classical ABPA is eosinophilic.
They are unlikely in non-eosinophilic asthma.
Reducing eosinophils reduces their formation.
Hydration helps clearance but does not prevent formation.

In simple terms:

Charcot–Leyden crystals are microscopic signs that the immune system is working too hard in the airways.

by GAtherton

Airways mucus and aspergillosis

A clear, patient-friendly explainer

People living with aspergillosis often say that mucus is one of the hardest symptoms to manage — thick sputum, coughing fits, plugs that feel “stuck”, and flare-ups that seem to come out of nowhere. This explainer brings everything together in one place: what mucus is for, why aspergillosis causes so much of it, why it becomes abnormal, and what current and future treatments aim to do.

1. What is airway mucus and why do we need it?

Mucus is normal, healthy, and essential. Everyone produces it all the time.

Its main roles are to:

Trap inhaled particles (dust, spores, bacteria, pollution)
Protect the airway lining from drying and irritation
Support the immune system
Clear the lungs, using tiny moving hairs (cilia) that sweep mucus upwards so it can be swallowed or coughed out
(this clearance system is called the mucociliary escalator)

In healthy lungs:

Mucus is thin
Produced in small amounts
Cleared without you noticing it

2. Why aspergillosis causes excessive mucus

In aspergillosis, the lungs are under ongoing stress. Several factors combine:

Persistent immune activation

The immune system keeps reacting to Aspergillus material in the airways. Even when the fungus is controlled, inflammation can persist.

Allergic-type inflammation (especially in ABPA)

Allergic immune responses strongly stimulate mucus-producing cells, leading to:

Large volumes of mucus
Very sticky or rubbery sputum

Airway damage

Conditions commonly associated with aspergillosis (such as bronchiectasis or long-standing asthma) cause:

Widened or damaged airways
Poor mucus clearance
Pools of mucus that are hard to shift

Slowed clearance

Inflammation and infection impair cilia, so mucus:

Moves more slowly
Sits in the lungs longer
Becomes thicker and harder to clear

➡️ What starts as a protective response becomes a self-perpetuating problem.

3. Why thick mucus causes symptoms

Excess or abnormal mucus can:

Block airways → breathlessness and wheeze
Trigger coughing → especially overnight or on waking
Trap infection → repeated flare-ups
Reduce oxygen exchange
Increase fatigue and chest discomfort

Many patients describe it as:

“Glue-like”, “stringy”, “rubbery”, or “impossible to move”

4. Mucus plugs and crystals – why some mucus is so hard to clear

Mucus plugs

When mucus becomes very thick, it can:

Form plugs that partially or completely block airways
Show up on CT scans
Worsen breathlessness suddenly

Charcot–Leyden crystals

In allergic and eosinophilic airway disease (including allergic bronchopulmonary aspergillosis):

Breakdown products of allergic immune cells can form microscopic crystals
These crystals make mucus:
- Stiffer
- More irritating
- Harder to clear

Their presence is a sign of ongoing allergic inflammation, not infection alone.

5. Why managing mucus really matters

Mucus is not just an inconvenience. Poor mucus control can:

Increase infection risk
Drive repeated exacerbations
Worsen lung damage over time
Reduce quality of life and sleep
Increase hospital admissions

For aspergillosis, mucus management is core treatment, not optional.

6. What helps now (current approaches)

A. Thin the mucus

Good hydration
Nebulised saline (normal or hypertonic)
Selected mucolytic medicines (used carefully)

B. Move it out

Regular airway clearance physiotherapy
Breathing techniques (e.g. active cycle breathing)
Oscillating devices (flutter, Acapella, Aerobika)
Gentle, regular physical activity where possible

C. Reduce inflammation

Inhaled corticosteroids (when appropriate)
Oral steroids (used cautiously)
Biologic therapies for selected allergic or eosinophilic disease
Antifungal treatment when fungal burden is contributing

D. Treat infections early

Bacterial infections thicken mucus further
Prompt treatment reduces long-term damage

7. What research is doing differently (emerging therapies)

Research is moving beyond simply “loosening mucus”.

1. Reducing mucus production at source

Scientists are developing drugs that aim to:

Switch off excessive mucus secretion
Preserve normal protective mucus

This targets the mucus-producing cells directly.

2. Blocking the signals that drive over-production

Inflammation sends chemical signals telling airways to make more mucus. New treatments aim to:

Calm allergic and immune pathways
Prevent expansion of mucus-producing cells

Some current biologic therapies already reduce mucus indirectly; future drugs will be more precise.

3. Changing mucus structure

Instead of thinning everything, researchers are studying ways to:

Loosen the internal “mesh” of mucus
Prevent dense plugs from forming
Restore normal movement by cilia

4. Targeting mucus crystals

In allergic aspergillosis, research is exploring how to:

Reduce crystal formation
Calm the specific immune responses that create them

5. New inhaled and physical approaches

Early trials are testing:

Inhaled therapies designed to mobilise secretions
Treatments that improve airflow behind mucus plugs

6. Precision medicine

Future mucus treatments are likely to be:

Personalised
Based on inflammation type, fungal involvement, airway damage, and immune markers

Two people with aspergillosis may have very different mucus drivers — and need different solutions.

8. What this means for patients today

There is no single “anti-mucus cure” yet
Promising therapies are in research and early trials
Safety and long-term effects must be proven first

For now:

Regular airway clearance remains essential
Treating inflammation and infection promptly is crucial
Understanding why your mucus behaves as it does helps guide treatment

Key messages to remember

Mucus is normally protective
Aspergillosis turns a helpful system into a problem
Thick, sticky mucus reflects ongoing inflammation and airway damage
Crystals signal allergic involvement, not just infection
Research is moving toward preventing abnormal mucus formation, not just thinning it

by GAtherton

When discharge from a specialist service is being discussed

A reassuring explanation for people with long-standing Aspergillus bronchitis

This page is for people who have lived for many years with a diagnosis of Aspergillus bronchitis, and who are now hearing that discharge from a specialist or tertiary service may be discussed, or is being gently considered.

Many patients tell us this brings up worries such as:

“Does this mean I’m less safe?”
“Does this mean they’re not sure anymore?”
“What if things get worse later?”

These feelings are very common, and they make sense.

First — nothing has been decided yet

If discharge is being discussed, it usually means:

Your team is reviewing your care carefully
They are looking at whether regular specialist follow-up is still helping right now
They are not withdrawing care, and not closing doors

Discussion is part of good medicine — especially with conditions that can change slowly over time.

Why might discharge even come up after many years?

This can feel surprising, but it is usually because:

Your condition has been stable for a long time
There has been no clear progression
Specialist treatments are not currently being changed
Ongoing follow-up may not be adding extra benefit at this stage

This is often a sign of relative stability, not doubt or disbelief.

Does this mean they think you never had Aspergillus bronchitis?

No — not at all.

What it usually means is:

Aspergillus bronchitis was a reasonable and helpful way to understand your symptoms at the time
Over time, the balance has shifted
Aspergillus may now be less active or less central to how you are feeling

Medical understanding evolves, and long-term conditions often change their shape rather than disappear or suddenly become “wrong”.

Does discharge mean Aspergillus is no longer important?

Not exactly.

It usually means:

“We don’t think Aspergillus is the main thing driving your symptoms right now.”

It does not mean:

“Aspergillus will never matter again.”

Your specialists know that Aspergillus-related problems can:

Fluctuate
Become more relevant during periods of illness or change
Need revisiting later on

That possibility is built into discharge planning, even if it is not always said clearly.

Why does this still feel unsettling?

Because specialist care often feels like a safety net.

You may have felt:

Known and understood by the team
Reassured by specialist oversight
Protected by regular review

Thinking about discharge can feel like losing that protection — even when nothing is actually changing day to day.

That emotional response is completely understandable.

What discharge from a specialist service usually does mean

If discharge does happen, it usually means:

Your care continues with your GP or respiratory team
Your history does not disappear
You are not starting from scratch
Re-referral is expected if things change

Specialist teams rarely intend discharge to be permanent or final.

What about being re-referred if things worsen?

This is one of the most important points — and a reassuring one.

In most cases:

Re-referral is anticipated
Patients previously known to the service are often reviewed more quickly
You do not need to “prove” everything again

Discharge usually comes with an open door, even if that door is not labelled as such.

What helps patients feel safer at this stage

It is reasonable to want:

A clear explanation of why discharge is being discussed
Reassurance that this is about now, not forever
Clarity about what would prompt a return
Confidence that your GP knows your history

These are normal needs — not demands.

What you might gently ask your team

You could ask:

“If my symptoms change, would re-referral be straightforward?”
“What sort of changes should prompt a review?”
“Will my GP have clear guidance from you?”
“Is discharge something we can review over time?”

These questions often help turn uncertainty into reassurance.

Key things to hold onto

Discussion of discharge usually reflects stability, not dismissal
It does not mean your past diagnosis was wrong
It does not mean you are being left unsupported
Re-referral is part of good planning, not failure
Feeling unsure or vulnerable at this point is very common

In gentle terms

Talking about discharge usually means “you are doing well enough not to need us right now” — not “you never needed us” and not “you’re on your own”.

by GAtherton

⭐ Aspergillus Bronchitis: The Overlooked Condition Hiding in Plain Sight

Estimated prevalence 1–2% in bronchiectasis and chronic airway disease clinics.

Aspergillus Bronchitis (AB) is a chronic, symptomatic infection of the airways caused by Aspergillus species in people with underlying lung disease. It sits between simple colonisation and chronic pulmonary aspergillosis (CPA), and is frequently overlooked or mislabelled as “recurrent infection,” “post-viral symptoms,” or uncontrolled bronchiectasis.

Unlike CPA, Aspergillus Bronchitis does not require cavities or major structural destruction — which makes it both easier to miss and surprisingly common among people with chronic airway disease.

When recognised and treated (usually with antifungal therapy for several months), symptoms often improve significantly. But because awareness remains low, most patients cycle through unnecessary antibiotics, repeated exacerbations, and worsening airway disease before the real cause is identified.

⭐ What Exactly Is Aspergillus Bronchitis?

Aspergillus Bronchitis is defined by:

chronic productive cough
sputum growing Aspergillus species repeatedly
airway inflammation
symptoms lasting over 3 months
underlying airway disease (bronchiectasis, CF, COPD, prior TB, ABPA)
response to antifungal therapy

Unlike ABPA:

there is no allergic response,
IgE is usually normal,
eosinophils are normal or mildly elevated.

Unlike CPA:

there are no cavities on imaging,
IgG may be normal or only slightly elevated,
disease is confined to the airways, not lung tissue.

This places AB in a “grey zone” — often invisible unless specifically looked for.

⭐ Why Aspergillus Bronchitis Is Missed

1. Symptoms mimic common chronic airway disease

Typical AB symptoms include:

daily productive cough
worsening sputum thickness
breathlessness
fatigue
repeated “chest infections”
slow-to-clear mucus
crackles or wheeze

These resemble:

bronchiectasis exacerbations
COPD flare-ups
chronic infection with Pseudomonas or NTM
post-viral cough
uncontrolled asthma

Without fungal awareness, clinicians default to bacterial explanations.

2. Sputum grows multiple organisms — Aspergillus is dismissed

In bronchiectasis, sputum frequently grows:

Haemophilus
Pseudomonas
Staphylococcus
Streptococcus
NTM

When Aspergillus appears, it’s often labelled:

“colonisation”
“contaminant”
“not clinically relevant”

But repeated isolation with persistent symptoms is highly suggestive of AB.

3. IgE/IgG results may be normal

Many clinicians expect high IgE or IgG to “confirm Aspergillus disease.”
But in Aspergillus Bronchitis:

IgE is usually normal
IgG can be normal or borderline

This leads to false reassurance.

4. Radiology rarely shows overt features

CT scans in AB may show:

mucus plugging
mild bronchial wall thickening
small nodules
progression of bronchiectasis

But they do not show the cavities of CPA or classic features of ABPA.

Therefore radiologists often report scans as “no significant change” or “stable bronchiectasis.”

5. Antibiotics appear to help — temporarily

Patients often improve slightly with:

amoxicillin
doxycycline
macrolides
ciprofloxacin

This gives clinicians the impression of bacterial disease, but symptoms soon return.

6. Lack of awareness

Many specialists (even in respiratory clinics) are unaware that Aspergillus Bronchitis:

exists as a distinct clinical entity
can be disabling
responds to antifungals
predicts progression to CPA if untreated

This leads to significant diagnostic delay.

⭐ Who Is at Highest Risk?

1. Bronchiectasis

The largest risk group.
Aspergillus Bronchitis may account for 1–2% of all bronchiectasis patients, and up to 5–10% in severe or frequent exacerbator groups.

2. Cystic Fibrosis (CF)

These patients frequently grow Aspergillus but not all have ABPA — some have Aspergillus Bronchitis.

3. COPD and chronic productive cough

Especially those with:

frequent mucus plugging
repeated “infective exacerbations”
progressive sputum production

4. Post-TB airway damage

Chronic airway deformity, scarring, and bronchiectasis from old TB predispose to fungal infection.

5. Post-COVID structural disease

A new and growing risk group, especially after prolonged ICU ventilation.

6. ABPA patients

Some patients develop Aspergillus Bronchitis during steroid-dominated treatment or after stopping antifungals.

⭐ Which Specialities Need Greater Awareness?

Respiratory medicine
(especially bronchiectasis clinicians and severe asthma teams)
Infectious Diseases
(frequent respiratory presentations with chronic airway infection)
Radiology
(to recognise subtle but progressive airway changes)
Primary care
(“recurrent chest infection” or “persistent cough” patients)
Physiotherapy & airway clearance teams
(excessive sputum with fungal elements)
Cystic Fibrosis services

The National Aspergillosis Centre is the ideal referral destination when diagnosis is uncertain or symptoms persist despite typical management.

⭐ Red Flags Suggesting Aspergillus Bronchitis

1. Chronic (>3 months) productive cough + repeated Aspergillus in sputum

Even 2 positive sputums in the right clinical context should raise suspicion.

2. Bronchiectasis patient not improving on repeated antibiotics

3. Thick, tenacious mucus with black, grey, or brown plugs

4. Worsening CT bronchiectasis or mucus plugging

5. Absence of features typical for ABPA (normal IgE, no fleeting infiltrates)

6. Asthma or COPD patient with new persistent sputum

7. Partial response to antibiotics but rapid relapse

8. Unexplained fatigue and breathlessness in someone with airway disease

⭐ The Cost of Missed Aspergillus Bronchitis

If AB is not recognised early, consequences include:

repeated exacerbations
accelerating bronchiectasis
long-term airway damage
chronic inflammation
steroid overuse
unnecessary antibiotics
repeated hospitalisations
progression to CPA in some patients

For health systems, missed diagnosis leads to:

higher admission rates
inappropriate long-term antibiotic use
avoidable CT scans and investigations
greater long-term burden of CPA

But antifungal therapy — when appropriately used — can offer marked symptom improvement and reduce exacerbation frequency.

⭐ Conclusion

Aspergillus Bronchitis is a distinct, treatable form of chronic airway disease seen in people with bronchiectasis, asthma, COPD, CF, and post-TB lung damage. Yet lack of awareness means many patients are repeatedly misdiagnosed with bacterial infections or unexplained chronic cough.

Recognising red flags, reviewing sputum results carefully, and considering antifungal therapy can dramatically improve outcomes. Early referral to specialist centres such as the National Aspergillosis Centre is recommended for complex cases or uncertain diagnosis.

Early identification prevents airway deterioration — and reduces the likelihood of progression to CPA.

by GAtherton

🟣 Aspergillus Bronchitis: A Patient Guide

If you've been diagnosed with bronchiectasis, COPD, or other chronic lung problems, and keep getting infections or mucus that tests positive for Aspergillus, you might be told you have Aspergillus bronchitis. But what does that mean? And how is it different from ABPA (Allergic Bronchopulmonary Aspergillosis)?

This guide explains what Aspergillus bronchitis is, how it’s diagnosed, how common it is, and how it differs from ABPA.

🌬️ What Is Aspergillus Bronchitis?

Aspergillus bronchitis is a chronic fungal infection of the airways caused by Aspergillus fumigatus. It happens in people with damaged or scarred airways, such as:

Bronchiectasis
COPD
Cystic fibrosis
Occasionally asthma (if structural damage exists)

It’s a low-grade infection, not an allergy and not an invasive disease. The fungus lives in the mucus lining the airways, causing persistent inflammation, infection, and symptoms.

🔍 What Are the Symptoms?

Common symptoms	What to know
Persistent cough	Often brings up sticky or brown mucus
Worsening breathlessness	Not always explained by asthma or infection alone
Fatigue or low energy	Common in chronic fungal infections
Frequent infections	May keep returning despite antibiotics
Wheeze	Sometimes, especially in asthma or ABPA overlap
Weight loss or low-grade fever	Possible in long-standing infection

📊 How Common Is It?

Aspergillus bronchitis is underdiagnosed but increasingly recognised — especially in patients referred to specialist centres.

Estimated frequency in different conditions:

Underlying condition	Estimated rate of Aspergillus bronchitis
Bronchiectasis	~5–15%, higher in referral centres
COPD	~1–5%, especially with steroid use
Cystic fibrosis	5–10% (non-allergic cases)
Asthma (alone)	Rare unless bronchiectasis is also present

It may be mistaken for a flare-up or chronic bacterial infection. Many people are told it’s “just colonisation” — but if symptoms persist and Aspergillus keeps growing in sputum, Aspergillus bronchitis should be considered.

🧪 How Is It Diagnosed?

There’s no single test. Diagnosis is based on clinical features plus evidence of fungal growth and a non-allergic immune pattern.

Test	What it shows
Sputum culture / PCR	Repeated detection of Aspergillus
Aspergillus IgG (blood)	Often raised, shows chronic exposure
Aspergillus IgE & eosinophils	Usually normal — helps exclude ABPA
CT scan	Shows bronchiectasis, mucus plugging, but no cavitation
Response to antifungals	Clinical improvement supports diagnosis

🔄 How Is It Different from ABPA?

ABPA is an allergic reaction to Aspergillus that mainly affects people with asthma or cystic fibrosis.
Aspergillus bronchitis, on the other hand, is a fungal infection in damaged airways, not an allergy.

Feature	Aspergillus Bronchitis	ABPA
Type of disease	Chronic fungal infection	Allergic lung disease
Immune markers	High IgG, normal IgE	High IgE and eosinophils
Sputum	Repeated growth of Aspergillus	May or may not grow
CT findings	Bronchiectasis, mucus	Central bronchiectasis, mucus plugs
Treatment	Antifungals only	Steroids ± antifungals
Typical patient	Bronchiectasis, COPD	Asthma (often severe), sometimes CF

Some patients can have both conditions at once, especially those with asthma and bronchiectasis — so testing is important.

💊 Treatment Options

Treatment	Purpose
Oral antifungals (itraconazole, voriconazole)	Main treatment — often for several months
Inhaled antifungals (e.g. nebulised amphotericin)	Alternative if oral drugs not tolerated
Airway clearance physiotherapy	Helps remove mucus and fungal load
Regular sputum testing	To monitor treatment response
Steroids	Not used unless there’s overlapping ABPA or asthma

🧠 Summary

Question	Answer
Is it an infection?	✅ Yes — fungal infection in the airways
Is it an allergy?	❌ No — that’s ABPA
Can it coexist with ABPA?	✅ Yes, in some cases
How is it diagnosed?	Repeated Aspergillus in sputum + high IgG + symptoms
How is it treated?	Antifungal medication (oral or nebulised)
Will it go away?	Often improves with treatment, but monitoring is essential

💬 What to Ask Your Doctor

Could my symptoms be from Aspergillus bronchitis?
Have I had sputum cultures and Aspergillus blood tests (IgG, IgE)?
Would antifungal treatment help me?
Should I be referred to a specialist centre (e.g. for CPA, ABPA, bronchiectasis)?
Am I on the best airway clearance and physiotherapy plan?

by GAtherton

Aspergillus Tracheobronchitis (ATB) for Expert patients and non-Specialist Clinicians

Expert Information for Patients, GPs, and Specialist Nurses

🔎 What Is Aspergillus Tracheobronchitis?

Aspergillus tracheobronchitis (ATB) is a rare but serious form of airway-invasive aspergillosis that primarily affects the trachea and large bronchi, rather than the lung parenchyma. It occurs predominantly in immunocompromised patients and may present with obstructive airway symptoms or respiratory failure.

ATB can exist on a spectrum from superficial colonisation to ulcerative or pseudomembranous invasion of the bronchial wall.

🧬 Pathophysiology

Inhaled Aspergillus spores adhere to and invade damaged airway mucosa.
Occurs more commonly when local airway immunity is impaired (e.g. in transplant recipients or critical illness).
May co-exist with invasive pulmonary aspergillosis (IPA) or appear in isolation.

👥 Who Is at Risk?

High-risk groups include:

Lung transplant recipients
Hematopoietic stem cell transplant patients
Severe COPD or structural airway disease
Patients with prolonged corticosteroid use
Critically ill or mechanically ventilated patients
COVID-19 or influenza patients (sometimes overlapping with CAPA/IAPA)

⚠️ Clinical Presentation

Symptoms depend on the degree of airway obstruction and depth of invasion:

Cough (dry or productive)
Worsening breathlessness
Stridor or wheeze
Hoarseness or vocal changes
Fever unresponsive to antibiotics
Haemoptysis (may be life-threatening)
Airway obstruction or collapse in advanced cases

ATB may be mistaken for tracheobronchial malignancy, infection, or stenosis.

🧪 Diagnosis

Bronchoscopy is essential for diagnosis:

Direct visualisation of:
- Ulceration
- Pseudomembranes
- Plaques
- Necrotic debris
Biopsies may reveal fungal hyphae invading mucosa.

Microbiological Investigations:

Culture and PCR for Aspergillus from BAL or brushings
BAL galactomannan
Serum galactomannan or β-D-glucan may be supportive
CT chest may be normal or show airway thickening, bronchial wall invasion, or tree-in-bud opacities

💊 Treatment

Systemic Antifungals:

Voriconazole is first-line
Isavuconazole or liposomal amphotericin B if azole intolerant or resistant

Airway Management:

Debridement or bronchoscopic removal of pseudomembranes in severe obstruction
Airway stenting in refractory strictures
Nebulised antifungals (e.g. amphotericin B) may be used as adjunct in selected cases

Prompt initiation of antifungal therapy is vital. Delays can lead to respiratory failure or death.

🧾 Monitoring

Clinical response: breathlessness, cough, fever
Repeat bronchoscopy in some cases
CT imaging of airways
Antifungal drug levels
Liver and renal function

📚 More Information

ATB is under-recognised, especially in non-neutropenic or critically ill patients.
Should be considered in transplant recipients or ICU patients with persistent respiratory symptoms and negative bacterial cultures.
Referral to respiratory, infectious diseases, and ICU teams is essential.
Resources: aspergillosis.org ; BTS Statement on aspergillosis

by GAtherton

Aspergillus Bronchitis for Expert Patients and non-Specialist Clinicians

Expert Information for Patients, GPs, and Specialist Nurses

🔎 What Is Aspergillus Bronchitis?

Aspergillus bronchitis is a chronic fungal infection of the airways by Aspergillus fumigatus (or rarely other Aspergillus species), seen in individuals with structural lung disease or impaired mucociliary clearance. Unlike ABPA, it is not allergic in origin and does not involve systemic invasion, but is characterised by persistent fungal colonisation with active infection.

🧬 Pathophysiology

Chronic colonisation of the conducting airways by Aspergillus
Local immune dysfunction (but not systemic immunosuppression)
Low-grade inflammation and increased mucus production
Often coexists with bronchiectasis, COPD, or CF

👥 Who Is at Risk?

Most commonly seen in patients with:

Bronchiectasis (non-ABPA)
Cystic fibrosis
COPD or asthma with sputum production
Post-viral or structural airway damage
Chronic antibiotic or corticosteroid use

Not typically seen in severely immunocompromised hosts (in whom invasive aspergillosis is more likely).

⚠️ Common Symptoms

Persistent productive cough
Thick sputum often yellow or green
Worsening breathlessness or wheeze
Chronic sputum positivity for Aspergillus
Mild fever or malaise (but often afebrile)
Poor response to antibiotics alone

Symptoms may resemble chronic bacterial bronchitis or overlap with infective exacerbations of bronchiectasis.

🧪 Diagnosis

Diagnosis requires a combination of clinical and microbiological evidence, with exclusion of ABPA and CPA.

Diagnostic Features:

Chronic productive cough (>4 weeks)
Repeated isolation of Aspergillus from sputum or BAL
Elevated Aspergillus IgG (typically present)
Normal or mildly elevated total IgE (typically <1000 IU/mL)
Absence of cavitary lesions or ABPA features on CT
Response to antifungal treatment supports diagnosis

🛑 Exclude:

ABPA (IgE >1000, eosinophilia, central bronchiectasis)
CPA (cavities, weight loss, radiological progression)

💊 Treatment

First-Line:

Oral antifungals (usually for 3–6 months)
- Itraconazole (first choice)
- Voriconazole or posaconazole (if resistant/intolerant)
Monitor drug levels and LFTs

Adjuncts:

Physiotherapy and airway clearance techniques
Nebulised saline or mucolytics
Treat co-infections (e.g. Pseudomonas) where relevant

In patients with CF, consider co-management with a specialist CF team.

🧾 Monitoring

Sputum cultures to monitor persistence or clearance
Aspergillus IgG levels
Symptoms (sputum, breathlessness)
Liver function and drug monitoring
Periodic CT imaging if symptoms worsen or haemoptysis occurs

📚 More Information

Aspergillus bronchitis is often underdiagnosed in patients with recurrent "non-resolving chest infections".
Patients benefit from coordinated care between respiratory, microbiology, and infectious disease specialists.
Referral to the National Aspergillosis Centre is appropriate for refractory or complex cases.
Resources: aspergillosis.org, Review: Pulmonary Aspergillosis: Spectrum of Disease;

Aspergillus bronchitis without significant immunocompromise
BTS Statement on aspergillosis

by GAtherton

How fungal spores interact with asthma and other lung diseases

Why Asthma Creates a Favourable Environment for Aspergillus

Mucus production

Allergic immune responses

Aspergillus Sensitisation

Severe Asthma with Fungal Sensitisation (SAFS)

Allergic Bronchopulmonary Aspergillosis (ABPA)

Asthma and Aspergillus Disease Pathway

When ABPA Causes Bronchiectasis

Aspergillus Bronchitis

Chronic Pulmonary Aspergillosis (CPA)

Aspergillosis and Immune Competence

Other Lung Diseases Linked to Aspergillus

Bronchiectasis

COPD

Tuberculosis

Key Messages

Further reading

Can Lungs Repair Themselves?

What New Research Means for People with CPA (and Other Aspergillosis)

The Discovery: A “Repair vs Defence” Switch

What “Repair” Means — and What It Does Not Mean

It does not mean:

What repair does realistically mean

Why Preservation Is a Major Goal in CPA

Why This Also Matters in ABPA

Where Development Has Reached

The Balance Challenge in Aspergillosis

What This Means for Patients Now

A Realistic and Hopeful Perspective

Reference

1️⃣ Could dissolving crystals reduce airway inflammation?

What we know

What this means biologically

How likely is this to help inflammation in humans?

2️⃣ Could dissolving crystals make mucus plugs easier to cough up?

Why mucus plugs are so thick in ABPA

Do we have direct evidence?

3️⃣ How strong is the overall case?

4️⃣ How does this compare to existing treatments?

5️⃣ Practical take-home message

🔭 The Bigger Picture

What are they? Why do they form? Do they matter?

🧬 What Are Charcot–Leyden Crystals?

🫁 Why Do They Appear in ABPA?

🌡 Is Most ABPA Eosinophilic?

❓ Are Crystals Caused by Aspergillus Infection?

🧠 Why Don’t All People with Asthma Develop These Crystals?

Type 2 (Eosinophilic) Asthma

Non–Type 2 (Non-Eosinophilic) Asthma

Neutrophilic asthma

Paucigranulocytic asthma

🧱 Do Charcot–Leyden Crystals Make Mucus Plugs Worse?

🎯 Do They Have a Purpose?

💧 Can Their Formation Be Reduced?

What reduces crystal formation?

📊 Do They Change Treatment?

🔎 What Do They Tell Us?

🧠 Key Points to Remember

A clear, patient-friendly explainer

1. What is airway mucus and why do we need it?

2. Why aspergillosis causes excessive mucus

Persistent immune activation

Allergic-type inflammation (especially in ABPA)

Airway damage

Slowed clearance

3. Why thick mucus causes symptoms

4. Mucus plugs and crystals – why some mucus is so hard to clear

Mucus plugs

Charcot–Leyden crystals

5. Why managing mucus really matters

6. What helps now (current approaches)

A. Thin the mucus

B. Move it out

C. Reduce inflammation

D. Treat infections early

7. What research is doing differently (emerging therapies)

1. Reducing mucus production at source

2. Blocking the signals that drive over-production

3. Changing mucus structure