Allergic Fungal Sinusitis
What Is A Fungus?
Fungi are organisms with plant-like attributes but do not have chlorophyll. Without chlorophyll, fungi survive by absorbing materials from deceased organic matter. Like bacteria, Fungi can break down almost any type of organic substances and plays a major role in the life cycle. Although Fungi are meant to feed off dead material, there are times when they start absorbing off organisms that are alive. When this happens, it is called a Fungal Infection. Treatment for this consists of eliminating the fungus and all of its sources.
Fungal Infections have seen a significant increase in the previous 30 years. Some causes of this may have come from immunosuppressive therapies, overuse of antibiotics, and overall increased awareness of such infections. When the immune system becomes suppressed, fungi discover openings to infect the body. Fungi do not need light and tend to live in moist and dark environments. With its damp conditions and dark cavities, the sinuses are a natural home for entering fungi. When Fungi invade the sinuses, it causes a condition known as Fungal Sinusitis.
There Are Four Types Of Fungal Sinusitis:
Mycetoma Fungal Sinusitis – Fugal balls or clumps of spores produce within the sinus cavity, often times occurring in the maxillary sinuses. This type of fungal sinusitis may occur while patient’s immune systems are fully effective. Causes of this may be due to an injury or trauma to the affected area. Symptoms may not show signs of inflammation but patients fell discomfort in the infected sinus area. Treatment for noninvasive Mycetoma Fungal Sinusitis consists of scrapping the infected sinus. Generally, anti-fungal therapy is not prescribed.
Allergic Fungal Sinusitis (ASF) – occurs when patients suffer allergic reactions to finely dispersed environmental fungus in the air. Patients that suffer from this condition are usually immunocompetent hosts (Able to incite a normal immune system response). ASF causes mucin and thick fungal debris to develop in the sinus cavities. Treatment requires the removal of such debris, in addition to the causing allergens. AFS recurrence is common but prescribed immunotherapy and anti-inflammatory medical therapies are preventative measures towards recurrence.
Note: During a Mayo Clinic Proceedings published in 1999, Allergic fungal sinusitis where present in subjects diagnosed with Chronic Rhinosinusitis. Cultures of nasal secretion from 96 percent of subjects with Chronic Rhinosinusitis showed to have fungus. For individuals who are sensitive to fungus, the immune system releases eosinophils that attack the fungus and causes irritation to nasal membrane. This irritation will last as long as the fungi infection exists.
Chronis Indolent Sinusitis – invasive form of Fungal Sinusitis that occur in people lacking a recognizable immune deficiency. This type of Fungal Sinusitis is most common in northern India and Sudan. Symptoms include facial swelling, chronic headaches, and visual impairment. This disease may advance from months to years. On a microscopic level, a granulomatous inflammatory infiltrate is the main characteristic of Chronic Indolent Sinusitis. Patients with a decreased immune system are at risk for this invasive disease.
Fulminant Sinusitis – A disease that may lead to an ongoing sinus destruction and may continue to the hone cavities that contain the brain and eyes. This type of Sinusitis is most commonly found in immunocompromised patients. These are individuals with a deficient immunologic mechanism due to immunosuppressive agents or immunodeficiency disorder.
Treatment for both the Chronic Indolent Sinusitis and Fulminant Sinusitis consists of surgery (for fungal removal) and anti-fungal therapy.
Content courtesy of AAO American Academy of Otolaryngology