Humidification

You’re coughing and sneezing and tired and achy. You think that you might be getting a cold. Later, when the medicines you’ve been taking to relieve the symptoms of the common cold are not working and you’ve now got a terrible headache, you finally drag yourself to the doctor. After listening to your history of symptoms and perhaps doing a sinus X-ray, the doctor says you have sinusitis.

Sinusitis simply means inflammation of the sinuses, but this gives little indication of the misery and pain this condition can cause. Chronic sinusitis, sinusitis that recurs frequently, affects an estimated 32 million people in the United States. Americans spend millions of dollars each year for medications that promise relief from their sinus symptoms.

Sinuses are hollow air spaces, of which there are many in the human body. When people say, “I’m having a sinus attack,” they usually are referring to symptoms in one or more of four pairs of cavities, or spaces, known as paranasal sinuses. These cavities, located within the skull or bones of the head surrounding the nose, include the frontal sinuses over the eyes in the brow area, the maxillary sinuses inside each cheekbone, the ethmoids just behind the bridge of the nose and between the eyes, and behind them, the sphenoids in the upper region of the nose and behind the eyes.

Each sinus has an opening into the nose for the free exchange of air and mucus, and each is joined with the nasal passages by a continuous mucous membrane lining. Therefore, anything that causes a swelling in the nose-an infection or an allergic reaction-also can affect the sinuses. Air trapped within an obstructed sinus, along with pus or other secretions, may cause pressure on the sinus wall. The result is the sometimes intense pain of a sinus attack. Similarly, when air is prevented from entering a paranasal sinus by a swollen membrane at the opening, a vacuum can be created that also causes pain.

Symptoms

Sinusitis has its own localized pain signals, depending upon the particular sinus affected. Headache upon awakening in the morning is characteristic of sinus involvement. Pain when the forehead over the frontal sinuses is touched may indicate inflammation of the frontal sinuses. Infection in the maxillary sinuses can cause the upper jaw and teeth to ache and the cheeks to become tender to the touch. Since the ethmoid sinuses are near the tear ducts in the corner of the eyes, inflammation of these cavities often causes swelling of the eyelids and tissues around the eyes and pain between the eyes. Ethmoid inflammation also can cause tenderness when the sides of the nose are touched, a loss of smell, and a stuffy nose. Although the sphenoid sinuses are less frequently affected, infection in this area can cause earaches, neck pain, and deep aching at the top of the head.

Other symptoms of sinusitis can include fever, weakness, tiredness, a cough that may be more severe at night, and runny nose or nasal congestion. In addition, drainage of mucus from the sphenoids down the back of the throat (postnasal drip) can cause a sore throat and can irritate the membranes lining the larynx (upper windpipe).

Causes

Most cases of acute sinusitis are caused by viruses and will clear up without treatment within two weeks. Viruses can enter the body through the nasal passages and set off a chain reaction resulting in sinusitis. For example, the nose reacts to an invasion by viruses that cause infections such as the common cold, flu, or measles by producing mucus and sending white blood cells to the lining of the nose, which congest and swell the nasal passages. When this swelling involves the adjacent mucous membranes of the sinuses, air and mucus are trapped behind the narrowed openings of the sinuses. If the sinus openings become too narrow to permit drainage of the mucus, then bacteria, which normally are present in the respiratory tract, begin to multiply. Most apparently healthy people harbor bacteria, such as Streptococcus pneumoniae and Haemophilus influenzae, in their upper respiratory tracts with no ill effects until the body’s defenses are weakened or drainage from the sinuses is blocked by a cold or other viral infection. The bacteria that may have been living harmlessly in the nose, throat, or sinus area can multiply and cause an acute sinus infection.

Medicines, too, can set off a nasal reaction with accompanying sinusitis. For example, intolerance to aspirin and other related non-steroidal anti-inflammatory medications, such as ibuprofen, can be associated with sinusitis in patients with asthma or nasal polyps (small growths on the mucous membrane lining of the sinuses).

Sometimes, fungal infections can cause acute sinusitis. Although these organisms are abundant in the environment, they usually are harmless to healthy people, indicating that the human body has a natural resistance to them. Fungi, such as Aspergillus and Curvularia, can cause serious illness, in people whose immune systems are not functioning properly. Some people with fungal sinusitis have an allergic-type reaction to the fungi.

Chronic inflammation of the nasal passages (rhinitis) also can lead to sinusitis. Allergic rhinitis or hay fever (discussed below) is the mostcommon cause of chronic sinusitis and is a frequent cause of acute sinusitis. Vasomotor rhinitis, caused by humidity, cold air, alcohol, perfumes, and other environmental conditions, also can result in a sinus infection.

Chronic Sinusitis

Chronic sinusitis refers to inflammation of the sinuses that continues for weeks, months, or even years.

As noted above, allergies are the most common cause of chronic sinusitis. Inhalation of airborne allergens (foreign substances that provoke an allergic reaction), such as dust, mold, and pollen, often set off allergic reactions (allergic rhinitis) that, in turn, may contribute to sinusitis. People who are allergic to fungi can develop a condition called “allergic fungal sinusitis.” As body cells react against these inhaled substances, they release chemical compounds, such as histamine, at the mucosal surface. These chemicals then cause the nasal passages to swell and block drainage from the sinuses, resulting in sinusitis.

Damp weather, especially in northern temperate climates, or pollutants in the air and in buildings also can affect people subject to chronic sinusitis.

Chronic sinusitis can be caused by structural abnormalities of the nose, such as a deviated septum (the bony partition separating the two nasal passages), or by small growths called nasal polyps, both of which can trap mucus in the sinuses.

Diagnosis

Although a stuffy nose can occur in other conditions, like the common cold, many people confuse simple nasal congestion with sinusitis. A cold, however, usually lasts about seven days and disappears without treatment. Acute sinusitis often lasts longer than a week. A doctor can diagnose sinusitis by medical history, physical examination, X-rays, and if necessary, MRIs or CT scans (magnetic resonance imaging and computed tomography).

Treatment

After diagnosing sinusitis and identifying a possible cause, a doctor can prescribe a course of treatment that will clear up the source of the inflammation and relieve the symptoms. Sinusitis is treated by re-establishing drainage of the nasal passages, controlling or eliminating the source of the inflammation, and relieving the pain. Doctors generally recommend decongestants to reduce the congestion, antibiotics to control a bacterial infection, if present, and pain relievers to reduce the pain.

Over-the-counter and prescription decongestant nose drops and sprays, however, should not be used for more than a few days. When used for longer periods, these drugs can lead to even more congestion and swelling of the nasal passages.

If symptoms do not improve within 10 to 14 days, the cause of sinusitis is likely to be bacterial. Most patients with sinusitis that is caused by bacteria can be treated successfully with antibiotics used along with a nasal or oral decongestant. A narrow-spectrum antibiotic — one that fights the most common bacteria — is the initial treatment recommended.

For many years, the combination of allergic disease and infectious sinusitis has been considered the most difficult form of sinus disease to treat. The patient with uncontrolled nasal allergies frequently experiences a lot of congestion, swelling, excess secretions, and discomfort in the sinus areas. Therefore, the patient should work with a doctor who understands the diagnosis and treatment of allergic diseases to pinpoint the cause of the allergies and follow an allergy care program to help alleviate sinusitis.

Doctors often prescribe steroid nasal sprays, along with other treatments, to reduce the congestion, swelling, and inflammation of sinusitis. Because steroid nasal sprays have no serious side effects, they can be used for long-term treatment. In some people, however, they irritate the nasal passages.

For patients with severe chronic sinusitis, a doctor may prescribe oral steroids, such as prednisone. Because oral steroids can have significant side effects, they are prescribed only when other medications have not been effective.

Although sinus infection cannot be cured by home remedies, people can use them to lessen their discomfort. Inhaling steam from a vaporizer or a hot cup of water can soothe inflamed sinus cavities. Another treatment is saline nasal spray, which can be purchased in a pharmacy. A hot water bottle; hot, wet compresses; or an electric heating pad applied over the inflamed area also can be comforting.

In treating patients with severe sinusitis, a physician may use special procedures. One technique requires the patient to lie on his back with his head over the edge of the examining table. A decongestant fluid is placed in the nose, and air is suctioned out of the nose so that the decongestant fluid can shrink the sinus membranes sufficiently to permit drainage. Or, a thin tube can be inserted into the sinuses for washing out entrapped pus and mucus.

Sometimes, however, surgery is the only alternative for preventing chronic sinusitis. In children, problems often are eliminated by removal of adenoids obstructing nasal-sinus passages. Adults who have had allergic and infectious conditions over the years sometimes develop polyps that interfere with proper drainage. Removal of these polyps and/or repair of a deviated septum to ensure an open airway often provides considerable relief from sinus symptoms. The most common surgery done today is functional endoscopic sinus surgery, in which the natural openings from the sinuses are enlarged to allow drainage.

Prevention

Although people cannot prevent all sinus disorders-any more than they can avoid all colds or bacterial infections-they can take certain measures to reduce the number and severity of the attacks and possibly prevent sinusitis from becoming chronic. Appropriate amounts of rest, a well-balanced diet, and exercise can help the body function at its most efficient level and maintain a general resistance to infections. Eliminating environmental factors, such as climate and pollutants, is not always possible, but they can often be controlled.

Many people with sinusitis find partial relief from their symptoms when humidifiers are installed in their homes, particularly if room air is heated by a dry forced-air system. Air conditioners help to provide an even temperature, and electrostatic filters attached to heating and air conditioning equipment are helpful in removing allergens from the air.

A person susceptible to sinus disorders, particularly one who also is allergic, should avoid cigarette smoke and other air pollutants.

Inflammation in the nose caused by allergies predisposes a patient to a strong reaction to all irritants. Drinking alcohol also causes the nasal-sinus membranes to swell.

Sinusitis-prone persons may be uncomfortable in swimming pools treated with chlorine, since it irritates the lining of the nose and sinuses. pers often experience congestion with resulting infection when water is forced into the sinuses from the nasal passages.

Air travel, too, poses a problem for the inpidual suffering from acute or chronic sinusitis. A bubble of air trapped within the body expands as air pressure in a plane is reduced. This expansion causes pressure on surrounding tissues and can result in a blockage of the sinuses or the eustachian tubes in the ears. The result may be discomfort in the sinus or middle ear during the plane’s ascent or descent. Doctors recommend using decongestant nose drops or inhalers before the flight to avoid this difficulty.

People who suspect that their sinus inflammation may be related to dust, mold, pollen, or food-or any of the hundreds of allergens that can trigger a respiratory reaction-should consult a doctor. Various tests can determine the cause of the allergy and also help the doctor recommend steps to reduce or limit allergy symptoms.

NIAID, a component of the National Institutes of Health, supports research on AIDS, tuberculosis and other infectious diseases as well as allergies and immunology.
Prepared by:

Office of Communications and Public Liaison
National Institute of Allergy and Infectious Diseases
National Institutes of Health
Bethesda, MD 20892

Public Health Service:

U.S. Department of Health and Human Services
June 1998