Complications:

Bacterial sinusitis is nearly always harmless (although uncomfortable and sometimes even very painful). If an episode becomes severe, antibiotics generally eliminate further problems. In rare cases, however, sinusitis can be very serious.

Osteomyelitis. Adolescent males with acute frontal sinusitis are at particular risk for severe problems. One important complication is infection of the bones (osteomyelitis) of the forehead and other facial bones. In such cases, the patient usually experiences headache, fever, and a soft swelling over the bone known as Pott's puffy tumor.

Infection of the Eye Socket. Infection of the eye socket, or orbital infection, which causes swelling and subsequent drooping of the eyelid, is a rare but serious complication of ethmoid sinusitis. In these cases, the patient loses movement in the eye, and pressure on the optic nerve can lead to vision loss, which is sometimes permanent. Fever and severe illness are usually present.

Blood Clot. Blood clots are another danger, although rare, from ethmoid or frontal sinusitis. If a blood clot forms in the sinus area around the front and top of the face, symptoms are similar to orbital infection. In addition, the pupil may be fixed and dilated. Although symptoms usually begin on one side of the head, the process usually spreads to both sides.

Brain Infection. The most dangerous complication of sinusitis, particularly frontal and sphenoid sinusitis, is the spread of infection by anaerobic bacteria to the brain, either through the bones or blood vessels. Abscesses, meningitis, and other life-threatening conditions may result. In such cases, the patient may experience mild personality changes, headache, altered consciousness, visual problems, and, finally, seizures, coma, and death.

Increased Asthma Severity

The relationship between sinusitis and asthma is unclear. A number of theories have been proposed for a causal or shared association between sinusitis and asthma. Successful treatment of both allergic rhinitis and chronic sinusitis in children who also have asthma may reduce symptoms of asthma. It is particularly important to treat any coexisting bacterial sinusitis in people with asthma. Patients might not respond to asthma treatments unless the infection is cleared up first.

Effects on Quality of Life

Pain, fatigue, and other symptoms of chronic sinusitis can have significant effects on the quality of life. This condition can cause emotional distress, impair normal activity, and reduce attendance at work or school. According to the American Academy of Allergy, Asthma, and Immunology, the average patient with sinusitis misses about 4 work days a year, and sinusitis is one of the top 10 medical conditions that most adversely affect American employers.