Other types of aspergillosis: Allergic Fungal Rhinosinusitis (AFRS)

(Also called Allergic Fungal Sinusitis, Allergic Aspergillus Sinusitis, Allergic Aspergillosis of the sinuses)

What is AFRS?

AFRS is a type of chronic sinus disease caused by an allergic reaction to fungi such as Aspergillus. It mainly affects adolescents and young adults, especially in warm and humid climates. AFRS accounts for about 5–10% of all cases of chronic sinusitis.

Unlike some other forms of fungal sinus disease, AFRS occurs in people with a normal immune system. It is not the same as an invasive fungal infection.

Symptoms

Common symptoms include:

• Blocked or congested nose

• Nasal polyps (soft swellings inside the nose)

• Post-nasal drip (mucus running down the back of the throat)

• Loss of smell or taste

• Recurrent sinus infections

• Headache or facial pressure

Pain is not typical — if severe pain is present, bacterial sinusitis may also be involved. Some people may have more dramatic problems such as worsening eye symptoms, changes in facial appearance, or very severe nasal blockage.

Diagnosis

Doctors may use a combination of:

• CT scans showing thickened sinuses with “allergic mucin” (thick mucus mixed with fungal debris).

• Nasal endoscopy to look for polyps and mucus.

• Laboratory tests for raised IgE (allergy antibody) or specific IgE against fungi.

• Biopsy or mucus samples, which sometimes show fungal filaments (though not always).

The diagnosis is sometimes difficult, as not every laboratory can reliably detect fungi in mucus.

Causes

AFRS is caused by an overactive immune response to fungi in the sinuses.

• The most common fungi are Aspergillus (especially A. flavus), Alternaria, and Curvularia.

• People with allergies, asthma, or nasal polyps are at higher risk.

Treatment

Treatment usually combines surgery and medical therapy.

• Surgery: Performed using an endoscope through the nose. The aims are to:

  1. Remove thick mucus and fungal debris.

  2. Improve drainage and ventilation of the sinuses.

  3. Allow future cleaning and access if disease comes back.

• Steroids: Corticosteroids are used to control inflammation and prevent relapse. These may be:

  • Tablets (short or long courses depending on severity)

  • Nasal steroid sprays or rinses (usually long-term)

• Other treatments:

  • Antifungal medicines are not clearly proven to help but may be tried in some cases.

  • Immunotherapy (allergy desensitisation) may help reduce recurrence.

  • Antibiotics such as azithromycin are occasionally added if bacteria are thought to play a role.

Despite treatment, recurrence is common. Many patients need repeat surgery or ongoing medical therapy.

Link with ABPA (Allergic Bronchopulmonary Aspergillosis)

AFRS affects the sinuses, while ABPA affects the lungs, but both are caused by an allergic reaction to Aspergillus and have many similarities.

• Some patients develop both AFRS and ABPA, sometimes called “sinobronchial allergic mycosis syndrome.”

• If you have AFRS and also develop asthma, persistent cough, or changes on a lung scan, your doctor may check for ABPA.

• Likewise, people with ABPA and severe sinus symptoms may be assessed for AFRS.

• If there is concern, your doctors may refer you to the National Aspergillosis Centre (NAC) in Manchester for specialist advice.

Key points for patients

• AFRS is not a dangerous invasive infection, but it is long-lasting and tends to come back.

• Surgery plus steroid treatment is the main approach.

• Ongoing follow-up is important because relapse is common.

• AFRS and ABPA can sometimes occur together, so chest symptoms should always be discussed with your doctor.