Sinusitis

Sinusitis

Sinusitis is inflammation of the sinuses, most commonly caused by an allergy or infection.

Sinusitis is one of the most common medical conditions. About 10 to 15 million people each year develop symptoms of sinusitis. Sinusitis may occur in any of the four groups of sinuses: maxillary, ethmoid, frontal, or sphenoid. Sinusitis nearly always occurs in conjunction with inflammation of the nasal passages (rhinitis), and some doctors refer to the disorder as rhinosinusitis. It may be acute (short-lived) or chronic (long-standing).

Acute Sinusitis: Acute sinusitis may be caused by a variety of bacteria and often develops after something blocks the openings to the sinuses. Such blockage commonly results from a viral infection of the upper airways, such as the common cold. During a cold, the swollen mucous membranes of the nasal cavity tend to block the openings of the sinuses. Air in the sinuses is absorbed into the bloodstream, and the pressure inside the sinuses decreases, causing pain and drawing fluid into the sinuses. This fluid is a breeding ground for bacteria. White blood cells and more fluid enter the sinuses to fight the bacteria; this influx increases the pressure and causes more pain.

Allergies also cause mucous membrane swelling, which blocks the openings to the sinuses. Additionally, people with a deviated septum are more prone to obstructed sinuses.

Chronic Sinusitis: Sinusitis is defined as chronic if it has been ongoing for more than 8 to 12 weeks. Doctors do not understand exactly what causes chronic sinusitis but it may follow a viral infection, a severe allergy, or exposure to an environmental pollutant. Often the person has a family history; a genetic predisposition appears to be a factor. If the person has a bacterial or fungal infection, the inflammation is much worse. Occasionally, chronic sinusitis of the maxillary sinus results when an upper tooth abscess spreads into the sinus above.

Symptoms and Diagnosis

Acute sinusitis usually results in pain, tenderness, and swelling over the affected sinus. Maxillary sinusitis produces pain over the cheeks just below the eyes, toothache, and headache. Frontal sinusitis produces headache over the forehead. Ethmoid sinusitis produces pain behind and between the eyes and headache, often described as splitting, over the forehead. The pain produced by sphenoid sinusitis does not occur in well-defined areas and may be felt in the front or back of the head.
In acute sinusitis, yellow or green pus may be discharged from the nose.

Fever and chills also can occur, but their presence may suggest that the infection has spread beyond the sinuses. Any change in vision or swelling around the eye is a very serious condition that can quickly—within minutes to hours—result in blindness. Such a change should be evaluated by a doctor as soon as possible.

The symptoms of chronic sinusitis are usually much more subtle, and pain occurs less often. The most common symptoms of chronic sinusitis are nasal obstruction, nasal congestion, and post-nasal drip. People with sinusitis may have colored discharge and a decreased sense of smell. A person also may feel generally ill (malaise).

A doctor makes the diagnosis based on the typical symptoms and, sometimes, on x-ray studies. X-rays may show fluid in the sinuses, but computed tomography (CT) is better able to determine the extent and severity of sinusitis. If a person has maxillary sinusitis, the teeth may be x-rayed to check for tooth abscesses. Sometimes a doctor passes a thin viewing scope (endoscope) into the nose to inspect the sinus openings and to obtain samples of fluid for culture. This procedure, which requires a local anesthetic, can be done in the doctor's office.

Treatment

Treatment of acute sinusitis is aimed at improving sinus drainage and curing the infection. Nasal sprays, such as phenylephrine , which cause blood vessels to narrow (constrict), can be used for a limited time. Similar drugs, such as pseudoephedrine, taken by mouth are not as effective. For both acute and chronic sinusitis, antibiotics such as amoxicillin or trimethoprim-sulfamethoxazole are given, but people who have chronic sinusitis take antibiotics for a longer period of time. Nasal corticosteroid sprays and corticosteroid tablets are helpful in reducing the inflammation in the mucous membranes. If significant allergy symptoms are present, antihistamines may be useful.

Nasal irrigations with salt water can help to cleanse the sinuses and keep them moist. When antibiotics are not effective, surgery may be performed either to wash out the sinus and obtain material for culture or to improve sinus drainage, which allows the inflammation to resolve.




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