The Cause of Sinusitis
There are many variables that can be the cause of sinusitis.
In a healthy state, sinuses contain no infection or other microorganism and is considered to be a sterile location. The opening in which the sinuses drain is called the ostia. When the ostia becomes blocked, infection can develop in the sinus cavities.
Inflammation, irritants, and allergies all have an impact on the cilia which is responsible for moving the mucus out of the sinuses.
The cause of sinusitis can be from anything that inhibits the cilia from working properly or anything that might obstruct the opening of the ostia. Sinus health requires an exchange of air between the nose and the sinuses. It also requires a flow of mucus to drain from the sinuses.
Below are a few things that can have an impact on the mucous membrane, the ostia, or the cilia which contribute to the cause of sinusitis.
Air Pollution: Air pollution refers to both indoor air pollution and outdoor air pollution. The EPA reports that indoor air can be much more polluted that outdoor air due to houses being built much tighter now for energy efficiency reasons. The general categories of air pollution are;
- Combustion products (cigarette smoke, wood burning stoves, gas appliances, etc.)
- Particulates (dust, pollen, asbestos, etc.)
- Chemicals (pesticides, formaldehyde, solvents, aerosol sprays, etc)
- Microorganism (bacteria, viruses, molds, dust mites, etc.)
Air pollution is known to be a contributing factor in the cause of sinusitis. The mucus plays a role in capturing these foreign particles and carrying them to the stomach for disposal. Sometimes air pollution can irritate the mucous membrane blanket and the cilia that moves it. The saturation of harmful particles can cause inflammation and swelling. This disruption of the mucus can have an effect on the sinuses draining and they may become clogged and obstructed which can lead to sinusitis. Furthermore, harmful particles that remain in the nose and sinuses can irritate the delicate lining and cause actual damage to them.
Allergies: Those who suffer from allergic rhinitis, also known as hay fever, are very susceptible to sinus infections. Nasal allergies are a major contributor to sinus problems.
- An allergy is when the body's immune system over responds to specific, noninfectious things such as pollen, dust mite debris, pet dander, mold and other "triggers." The antibodies in the blood have attached themselves to mast cells. The attack takes place by IgE antibodies signaling to the mast cells to release histamine and other inflammatory chemicals. Histamine affects the body and produces what we call allergy symptoms.
When an allergic reaction takes place, there is swelling of the mucous membrane and obstruction to the sinuses from being able to drain properly. Preventing the sinuses from draining is a major cause of sinusitis. The combination of increased mucus flow and a swollen sinus lining overwhelms the cilias' abilities to sweep out the mucus, which then becomes infected. As many as 70 to 80 percent of those with sinusitis have allergies.
Climate: Climates appears to play a significant role in producing sinusitis symptoms. Hot and humid climates often present a problem for those who are allergic to molds. Fungi thrive in warm, hot, wet, or humid climates. There is no doubt that climate plays a role. On the other hand, sometimes for those who are blaming the climate are actually having problems with air pollution or allergens.
Cocaine Use: The majority of users sniff or snort this drug through the nose. Along with causing inflammation and nosebleeds, hoarseness can also occur. Over time, the mucous membranes in the nose dry out and crust. Over time, damage occurs making it very difficult to treat inflammation and nasal congestion and overcoming the obstruction that can develop. This is certainly one cause of sinusitis that can be avoided.
Cold Air: Cold temperatures can shock the mucous membrane and impair the function of the cilia. The cilia is what is responsible for moving the mucus out of the sinuses. When they are not functioning well, infection in the sinuses can develop and be a cause of sinusitis. Notice how cold air sometimes make your nose run.
Common Cold: It can be difficult to distinguish between a cold and acute sinusitis. Often, sinus infection is a cold that has lasted longer that ten days. It is not uncommon to hear stories of a lifetime of sinus problems that began with the common cold. Normal sinus health requires air and mucus to be able to flow freely between the nose and the sinuses. The common cold inflames the mucous membrane and inactivates the cilia. As a result, mucus produce by the sinuses cannot drain and provides a breeding ground for bacteria. This pooling of mucus can easily lead to a sinus infection and be the cause of sinusitis.
Concha Bullosa: Concha refers to the turbinates in the nose and bullosa refers to a ballooning-like structure. The middle turbinate is where some of the sinuses drain to. When the turbinate enlarges and blocks this opening to the sinuses, air exchange and mucus flow between the nose and the sinuses cannot take place.
Dental Problems: A tooth infection is usually a bacterial infection. The upper teeth are in close proximity to the maxillary sinuses and separated only by a paper thin bone. An infection in the upper teeth can spread to the sinus cavities.
Dry Air: One of the functions of the sinuses is to add moisture to the air before it reaches the lungs. For those who are prone to sinusitis, dry air may be hard on their sinuses. Dry air is especially hard on the cilia that moves the mucus to the back of the throat and keeps the sinuses healthy. Dry air is a common cause of sinusitis because so many houses uses air conditioning, wood burning stoves or forced-air heating which tends to dry out the air.
Emotional Stress: An unhealthy lifestyle can be a result of ongoing stress and these bad habits increase the risk for disease. The emotional stress can be a factor in the development of a disease. The medical community continues to develop and provides us with the conclusion that our attitudes, beliefs, feelings, and thoughts have an impact on our immune system and on our health. Many physicians observe this in the recovery rooms.
Heredity: A predisposition to sinusitis and allergies seem to play a role although the effects may be subtle. We seem to develop the likelihood of developing the condition and not inheriting a specific condition. The mother may have pet allergies and the child develops dust mite allergies. One family member may have a mild case of sinusitis while another may have chronic sinusitis or no problems at all.
Immune Deficiency: It is the immune system that is the body's defense mechanism against infection and disease. The medical community does not always understand why the immune system might not function normally. It is still not understood why one person may have a reaction to pollen and another person does not. Immune deficiency is when the body lacks one of the infection-fighting proteins or antibodies called immunoglobulins. A blood test can determine the condition of your immune system.
Infection: Infections are a common cause of sinusitis. Determining the type of infections is important in determining treatment. Antibiotics may have an affect on a bacterial infection but would have no impact on a virus.
- Viruses: A virus is a small infectious organism that is smaller than bacteria or fungi. They multiply by attaching to a cell and releasing their DNA and thus, taking over the function of the cell. Viruses can be transmitted from person to person and hand washing is very beneficial when dealing with viral infections.
- Bacteria: Bacteria are a single cell organism. They thrive in dark, moist places and our sinuses provides such a place. They can reproduce very quickly and infections can become extremely serious if not treated properly. On the other hand, they are very useful to us. Without bacteria in our intestines, we would not be unable to absorb nutrients from our food.
- Fungus: Fungi are plant-like organisms. The difference between them and other plants is that they do not produce chlorophyll. They do not need sunlight. They also like to grow in moist dark places including around our toes. Many people are allergic to fungi.
Inflammation: The major cause of sinusitis treatment. Inflammation prevents the cilia from performing its function of moving the mucus out of the sinuses. The membranes swell, the mucus flow stops and the sinuses become clogged. The sinuses become sealed off and the moisture trapped inside allows bacteria to multiply to unsafe levels.
Injury: The nose is designed to move air a specific way. When injury or trauma occurs, the pathway may be altered. The flow of the mucus may also be affected allowing for the opportunity of sinusitis to develop. An abnormal growth can possibly develop and symptoms may not occur until years later when the growth become larger.
Malformations: Malformations are physical problems that result in the obstruction of the tiny openings in which the sinuses drain. Given the narrow passageway in which the sinuses drain, it is no surprise that even the small growths can obstruct the draining process and be the cause of sinusitis. The most common malformations are;
- Deviated Septum: The septum is the structure compose of cartilage that divides the nose into two nostrils. When it become significantly bent or buckled, it is know as a 'deviated nasal septum.' A slight deviation usually presents no problems. But a more severe deviation can impair the ability of the sinuses to clear mucus which can predispose them to infection in the sinuses. People can be born with this condition or it can be caused from injury.
- Enlarged Adenoids: One of the common problems that occur in children and may predispose them towards sinusitis. These children may also have problems sleeping. Dental deformities in these children develop due to breathing primarily through their mouth.
- Polyps: This pear-shape and smooth growth is not precancerous. They are usually a manifestation of chronic inflammation. They are a major cause of sinusitis because they block the airway and cause the mucus to back up and become infected due to their size and position in the nose.
- Cyst: A cyst is a membranous sac filled with fluid. They are a rounded and smooth structure. Because of their position and size, they too can block the sinuses from draining and have to be removed.
- Turbinates: Turbinates are part of the nose anatomy that warms and humidifies the air that we breathe. Concha bullosa is an enlarging or ballooning of the middle turbinate. The sinuses drain next to the middle turbinate so an enlargement can block the drainage hole.
- Tumors: Although the normal tumor (abnormal growth) are benign, they do need to be removed because they can become cancerous (malignant). But don't equate the term benign (non-cancerous) to mean the same as harmless. These growths also block the sinuses from draining and interfere with the mucus flow which is the cause of sinusitis.
Occupational Hazards: Anything that irritates the nose has the potential to disrupt the function of the cilia which would lessen the ability of the sinuses to drain. Occupations where there are a lot of irritants in the air should be considered a high risk to the sinuses. Occupations could include: firemen, painters, construction workers, auto mechanics, parking garage attendants, and offices where there are smokers.
Sick-Building Syndrome: This condition is one in which people live or work or visit a building and experience symptoms and yet no specific illness can be identified. Symptoms may include headaches, dizziness, nausea, fatigue, itchy skin, coughing, and eye irritation. Nasal congestion may also occur and sinusitis may develop in those who have a predisposition towards sinus problems. More times than not, the cause of sick-building syndrome usually occurs because the building re-circulates the air without a sufficient supply of fresh air and without a proper cleaning of the air.
Smoke: It is hard to name anything more harmful to the body's filter system than smoke. And cigarette smoke with nicotine paralyzes the cilia and eventually damages them. This causes the mucus to become thicker and to accumulate. This situation also causes inflammation of the mucous membrane which can block the sinuses from draining. Research shows that nonsmokers who live with or work with smokers are also adversely affected.
Swimming and Diving: Swimming in polluted waters can have an affect on anyone. But those with a predisposition to sinusitis even suffer when swimming in chlorinated water. It irritates the mucus membrane which causes swelling. Diving is a problem for those who have sinusitis because the change in air pressure may provoke an attack.
What ever may irritate the nose and trigger symptoms, the cause of sinusitis usually results from a couple of things:
- The mucous membrane becomes swollen and inflamed.
- The cilia stop working properly.
- The openings in which the sinuses drain become blocked.
- Infection develops in the sinuses.These four things are essentially the cause of sinusitis although as seen above, many things, variables, or events may trigger these conditions to develop in the nose.
To learn more about the cause of sinusitis, the National Institute of Allergy and Infectious Diseases provides good information.