Sinusitis.

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, examining your face and forehead, 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 persists for at least 3 weeks, 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.

However, most patients with sinusitis have pain or tenderness in several locations, and symptoms usually do not clearly define which sinuses are inflamed.

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 (or other sinuses) down the back of the throat (postnasal drip) can cause a sore throat and can irritate the membranes lining the larynx (upper windpipe). On rare occasions, acute sinusitis can result in brain infection and serious complications.

Causes

Most cases of acute sinusitis are preceded by virus-induced "colds." These viral "colds" do not cause symptoms of sinusitis, but they do cause inflammation of the sinuses. Both the "cold" and the sinus inflammation usually resolve without treatment in two weeks. However, the inflammation might explain why colds increase the likelihood of developing acute 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 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 or throat can multiply and cause an acute sinus infection.

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, 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) may be complicated by episodes of acute sinusitis. Patients with allergic rhinitis also often have chronic sinusitis. Vasomotor rhinitis, caused by humidity, cold air, alcohol, perfumes, and other environmental conditions, also may be complicated by sinus infections.

Acute sinusitis is much more common in certain patients than in the general population. For example, sinusitis occurs more often in patients with reduced immune function (such as patients with immune deficiencies and HIV infection) and with abnormality of mucus secretion or mucus movement (such as cystic fibrosis and diseases of abnormal cilia [Kartagener's syndrome]).

Chronic Sinusitis

Chronic sinusitis refers to inflammation of the sinuses that continues for at least 3 weeks, but often continues for months or even years.

As noted above, allergies are frequently associated with chronic sinusitis. Patients with asthma have a particularly high frequency of chronic sinusitis. Inhalation of airborne allergens (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."

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

Like acute sinusitis, chronic sinusitis is more common in patients with immune deficiency or abnormalities of mucus secretion or movement (e.g., immune deficiency, HIV infection, cystic fibrosis, Kartagener's syndrome). In addition, some patients have severe asthma, nasal polyps, and severe asthmatic responses to aspirin and aspirin-like medications (so-called non-steroidal anti-inflammatory drugs, or NSAIDs). These latter patients have a high frequency of chronic sinusitis.

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 7 to 14 days and disappears without treatment. Acute sinusitis often lasts longer and typically causes more symptoms than just a cold. 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 reduce the inflammation and relieve the symptoms.

Acute 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 drags can lead to even more congestion and swelling of the nasal passages.

Most patients with sinusitis that is caused by bacteria can be treated successfully with antibiotics used along with a nasal or oral decongestant. An antibiotic that fights the bacteria most commonly associated with sinusitis is the initial treatment recommended.

Many cases of acute sinusitis resolve without antibiotics. However, patients with underlying allergic disease, and infectious sinusitis, need to be treated to relieve their allergy symptoms. Patients with asthma and infectious sinusitis often have exacerbations of asthma which need to be treated. Many physicians feel that some patients with severe asthma have dramatic symptom improvement when their chronic sinusitis is treated with antibiotics.

Doctors often prescribe steroid nasal sprays, along with other treatments, to reduce the congestion, swelling, and inflammation of sinusitis.

Chronic sinusitis is often difficult to treat successfully, as symptoms persist even after prolonged courses of antibiotics. In general, the treatment of chronic sinusitis, such as with antibiotics and decongestants, is similar to treatment of acute sinusitis. However, the role of bacterial infections, and hence the usefulness of antibiotics in treating chronic sinusitis, is debated. Steroid nasal sprays are commonly used to reduce inflammation in chronic sinusitis. Although these nasal sprays are occasionally used for long-term treatment for patients with chronic sinusitis, the long-term safety of these medications, especially in children, is not fully understood, and the benefits and risks need to be balanced. 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.

When medical treatment fails, surgery may be the only alternative for treating chronic sinusitis. Studies suggest that the vast majority of patients who undergo surgery have fewer symptoms and better quality of life. 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 nasal 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. This type of surgery is less invasive than conventional sinus surgery and serious complications are rare.

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.

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. Divers 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 individual 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.

Additional information on sinusitis is available through MEDLINE Plus, a service of the National Library of Medicine. You can access MEDLINE Plus at the following Web site: http://www.nlm.nih.gov. If you do not have Internet access, ask a librarian for assistance.

NIAID, a component of the National Institutes of Health (NIH), supports research on AIDS, tuberculosis, malaria, and other infectious diseases as well as allergies and immunology. NIH is an agency of the U.S. Department of Health and Human Services.

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 April 1999