Researchers from the University of California in San Francisco recently performed a study of the microbiome of the human nose, which provided clues to the cause of a chronic sinus condition, as well as a potential strategy for a cure.
The condition, which is known as chronic rhinosinusitis (CRS), is characterized by inflammation of the nasal and paranasal sinuses, usually lasting over 12 weeks. Patients who suffer from this disease experience a variety of symptoms, such as congestion, fatigue, and even depression. It can also lead to other conditions, like asthma, meningitis, and aneurysms. The condition is estimated to be responsible for as many as 22 million office visits every year, and more than 500,000 emergency department visits.
Understanding Our Sinuses
Our sinuses consist of small chambers in the face and skull bones, next to the nasal cavity that have narrow openings into the nasal cavity. That, in turn, allows drainage of mucous out of the sinuses. Since healthy sinuses assist in clearing excess mucus, a sinus blockage from a viral upper respiratory infection or nasal allergies can lead to fluid accumulation, increasing the probability of a bacterial infection.
While the causes of chronic rhinosinusitis are not completely understood, it is commonly defined as a group of disorders characterized by inflammation of the mucosa of the nose and paranasal sinuses of at least 12 weeks duration. We have come to realize that it is really a spectrum of diseases; there are a number of disorders that cause chronic inflammation of the nose and paranasal sinus.
Clues to the Cause of Chronic Sinusitis
Unfortunately, the causes of chronic rhinosinusitis are not completely understood. This has, in turn, hampered development of long-lasting, definitive treatments.
The researchers knew that the fast-growing body of literature that demonstrates associations between the human microbiome composition and several diseases, such as asthma and obesity, which is why they hypothesized that a nasal microbiome exists, and plays a role in chronic rhinosinusitis development.
For the study, the researchers from the University of California compared the nasal microbial communities of ten chronic rhinosinusitis patients and ten healthy individuals. They found that patients with chronic rhinosinusitis had a depleted nasal microbiome, which is characterized by a significant reduction in bacterial diversity, as well as an overgrowth of one type of bacteria, identified as Corynebacterium spp.
The researchers investigated their hypothesis using a mouse model. To recreate a depleted microbiome, mice were administered antibiotics for seven days, and then infected with C. tuberculostearicum. Mice who were given the antibiotic before exposure displayed symptoms of sinusitis. Mice that were not first treated with antibiotics but exposed to the bacteria did not.
The researchers noted that lactic acid bacteria were significantly depleted in patients with chronic rhinosinusitis, which suggests that his bacterium may have a protective role against chronic rhinosinusitis development.
These findings suggest that manipulation of microbial communities to restore colonization by beneficial species identified in this study may represent a novel and efficacious approach for prevention or management of chronic rhinosinusitis.
While the findings certainly are interesting, and eventually may lead to the prevention of management of chronic rhinosinusitis, more research is needed.
If you are suffering from sinus related conditions and are actively seeking treatment, schedule a consultation with Beverly Hills sinus expert Dr. Larian by calling 310.461.0300 today!