According to a study, two highly common respiratory conditions, allergic rhinitis and asthma, are caused by different fungi. Researchers conducting a study in Portugal revealed that people with allergic rhinitis and asthma have different fungi, or mycobiomes, in their noses than healthy individuals.

Allergic rhinitis is a condition that causes sneezing, itching and runny nose, affecting about one in four adults in Portugal. This common respiratory problem, often associated with asthma, is caused by an overreaction of the immune system to allergens such as dust, pollen or fungus.

Asthma is a long-term condition that affects the airways in the lungs, causing them to swell and narrow. This makes breathing difficult and may cause coughing, wheezing, or chest tightness, especially during a flare-up.

The findings, led by Dr. Luis Delgado of the University of Porto, share new clues about how these conditions develop and possible ways to treat them.

What did the study find?

The study, published in Frontiers in Microbiology, involved 214 participants, including children and young adults, from an immunology and asthma clinic in Porto.

Of these, 155 had both allergic rhinitis and asthma, 47 had rhinitis only, and 12 had asthma. The researchers also included 125 healthy individuals for comparison.

Using nasal swabs, the team analyzed the fungi in participants’ noses and found that people with allergic rhinitis had more diverse fungal communities than healthy individuals.

“Allergic rhinitis samples showed significantly greater fungal diversity and a different fungal composition,” Dr. Delgado said. This suggests that allergic rhinitis not only alters the nasal microbiome but may also play a role in inflammation and airway disease.

Fungal and Disease Infections

The study found that certain fungi commonly found in the nasal passages may act as allergens or even contribute to disease progression.

In patients with both allergic rhinitis and asthma, fungal communities were more interconnected, indicating that fungi may influence the nasal immune environment.

Additionally, the researchers identified three metabolic pathways associated with DNA and RNA production that were more active in patients with allergic rhinitis and asthma. These pathways may become targets for future therapies.

More research is needed

Dr. Delgado said the study provides an important first step in understanding the connection between nasal fungus and respiratory diseases. However, they stressed the need for long-term studies to determine how fungal communities change over time and whether they directly contribute to these conditions.

“Our findings open the door to further research, and we hope others will build on this work to develop treatments that will improve patients’ lives,” he said.