Overview, Causes, & Risk Factors
Sinusitis is an inflammation or infection of the linings of the sinuses and cavities of the nose. There are three major types of sinusitis:
acute sinusitis, which involves less than 3 weeks of symptoms
subacute sinusitis, with symptoms lasting 3 weeks to 3 months
chronic sinusitis, in which symptoms last longer than 3 months
What is going on in the body?
There are four pairs of sinuses which connect to the nose and throat. The sinuses are normally filled with air. They moisten, cleanse, and warm the air after it leaves the nose on the way to the lungs. The normal nose is a wonderful filter. It removes 80% of all tiny particles.
Acute allergic sinusitis occurs when the lining of the nose and sinuses becomes inflamed. Common causes include pollens, animal dander, and other allergens. These allergens set off an inflammatory response. Histamine and other chemicals are released, causing the symptoms of acute allergic sinusitis.
Viral sinusitis can occur together with an upper respiratory infection, or URI. Viruses attack the lining of the sinuses and cause swelling of the nasal tissues, which leads to symptoms.
Bacterial sinusitis can follow a viral infection if bacteria grow inside the sinuses. About 5 out of every 1,000 viral URIs are complicated by a bacterial sinus infection. Bacterial forms of sinusitis also occur when the drainage opening is blocked by swelling or narrowing. Then the normal bacteria in the sinus and nasal tracts overgrow and cause an infection.
Cold air sinusitis produces symptoms when the person is exposed to cold air. Aspirin sensitivity sinusitis may occur in some individuals when they take medicines containing aspirin.
What are the causes and risks of the condition?
Sinusitis may be caused by a virus, bacteria, allergen, or other factors as outlined above. People with immunodeficiency disorders are at higher risk for some types of sinusitis.
Symptoms & Signs
What are the signs and symptoms of the condition?
Symptoms of sinusitis vary, depending on the cause and type of sinusitis.
Acute allergic sinusitis may cause:
clear, watery discharge from both sides of the nose
nasal and ear itching
tearing and eye itching
Viral sinusitis can cause the following symptoms:
fever and chills
muscle aches and joint pain
sore throat and hoarseness
Viral sinusitis will spontaneously resolve in 10 to 14 days. Sometimes an episode can last 21 days. Viral sinusitis is common in the fall, winter, and early spring.
Bacterial sinusitis in adults can produce the following symptoms:
discolored nasal drainage
Bacterial sinusitis in children may cause:
green to yellow nasal discharge
The symptoms of bacterial sinusitis follow one of three patterns. The most common is symptoms that worsen over time. The second pattern is symptoms that last longer than 3 weeks. This is often described as a cold that won't go away. The third pattern is the sudden onset of severe upper respiratory symptoms.
Cold air sinusitis may cause these symptoms:
clear nasal discharge
Dry air sinusitis is often seen in the winter months and may cause:
yellow to slightly bloody crusting, especially in the front part of the nose
Aspirin sensitivity sinusitis may cause:
long-term facial pain
loss of smell
nasal polyps, which are growths that protrude from the mucous membrane
very thick, white or yellow nasal discharge
Diagnosis & Tests
How is the condition diagnosed?
Diagnosis of sinusitis begins with a medical history and physical exam. The healthcare provider may order additional tests, such as:
blood and urine tests
cultures of nasal secretions
Prevention & Expectations
What can be done to prevent the condition?
Many cases of sinusitis can be avoided by preventing an upper respiratory infection. Avoiding crowded places and infected people can lessen the risk of catching a virus. Influenza or flu vaccination can help prevent infection by the influenza virus. Careful hand washing and disposal of tissues can help prevent the spread of sinusitis. Individuals should follow the healthcare provider's recommendation for good control of nasal allergies.
What are the long-term effects of the condition?
If sinusitis is untreated, the individual may have serious long-term effects, including:
infection of the eye socket
meningitis, or infection of the brain linings
chronic facial pain
loss of smell
What are the risks to others?
Most forms of sinusitis are contagious from person to person.
Treatment & Monitoring
What are the treatments for the condition?
Treatment varies, depending on the cause and type of sinusitis. Some common treatments include:
avoiding triggers, such as cold air or allergens
increased oral fluids
saline nasal spray or rinses
warm compresses on the face
What are the side effects of the treatments?
Side effects depend on the medicines used. Brief use of topical decongestants has few side effects. Long-term use can cause progressive inflammation in the nose.
What happens after treatment for the condition?
Most cases of sinusitis go away on their own or with treatment. Some individuals may develop chronic sinusitis.
How is the condition monitored?
Any new or worsening symptoms should be reported to the healthcare provider.