David Nash, M.D.
Assistant Professor of Pediatrics
Children's Hospital of Pittsburgh
Ellen Wald, M.D.
Professor of Pediatrics
Children's Hospital of Pittsburgh

What is sinusitis?

Sinusitis is the inflammation of one or more of the sinuses. At birth, the maxillary sinuses are found behind each cheek bone on each side of the nose. Initially, the maxillary sinus is a very small, slit-like space. As a child grows, the maxillary sinus becomes large enough to hold at least three teaspoons of fluid. The ethmoid sinuses also are present at birth, and they are located on each side of the bridge of the nose.

The ethmoid sinuses are comprised of many individual little air spaces. At about six or seven years of age, a child begins to develop the frontal sinuses. The frontal sinuses are located in the forehead just above the eyes. A fourth sinus space exists behind the ethmoid sinuses, and it is known as the sphenoid sinus. Each sinus is carpeted by the mucosa, a thin lining of cells and mucus.

Swelling of the mucosa and fluid collection in the sinuses cause the inflammation associated with sinusitis. Each sinus also possesses a very small drainage track (about the size of a pinhead) that empties into the nose. The diagram illustrates the position of the sinuses.

Physicians have divided arbitrarily (and with some controversy) patients with sinusitis into three groups depending on the duration of the symptoms. Patients are considered to have acute sinusitis when the symptoms have been present for less than four weeks. Patients are considered to have chronic sinusitis when the symptoms have persisted longer than 12 weeks.

The term "subacute sinusitis" is used to describe the symptoms that persist longer than 4 weeks, but less than 12 weeks. However, some physicians eliminate the "subacute" group because of its similarities to acute sinusitis. Decisions about the cause of sinusitis, the appropriate diagnostic testing, and the treatment options for it are based on the duration of the symptoms.


What causes sinusitis?

Persistent blockage of the narrow sinus drainage tracks can cause sinusitis. The sinus drainage tracks can be blocked because of: 1) swelling of the mucus membrane that lines these tracks; 2) a change in the quality (thicker/stickier) of the mucus, leading to the impaired flow of the mucus; or 3) physical blockage of the drainage path due to polyps or bony abnormalities. The most common causes of blockage are from viral upper respiratory infections ("colds") and allergies.

The majority of patients develop acute bacterial sinusitis as a complication of a viral upper respiratory infection. Approximately 5% to 10% of colds ultimately lead to bacterial sinusitis. The nasal sniffing and blowing associated with colds push secretions that contain bacteria into the sinus drainage tracks. If the drainage tracks become completely and persistently blocked, a fertile environment for bacterial growth is created within the sinus. Bacteria cause the vast majority of cases of both acute and subacute sinusitis.

The cause of chronic sinusitis is not well understood. Although both patients and physicians often blame bacterial infection as the cause of chronic sinusitis, there are few data to support this theory. In fact, anecdotal experience in patients with chronic sinusitis frequently shows a poor response to antibiotics, suggesting that bacterial infection is not the main problem for these patients.

An alternate theory for the development of chronic sinusitis is based on the persistent exposure to allergens and irritants (e.g., tobacco smoke). Chronic exposure to these agents can cause either swelling of the mucus membrane or changes in the quality of secreted mucus, leading to blockage of the sinus drainage tracks and, ultimately, chronic sinusitis.

Rarely, the cause of chronic sinusitis may be because of either abnormal mucus secretions (cystic fibrosis) or abnormal mucus movement (immotile cilia syndrome). Almost all patients with immune disorders develop chronic sinusitis due to an increased susceptibility to infection.


Who gets sinusitis?

Both adults and children can get acute sinusitis; in fact, it is one of the most common complaints reported by patients to their primary care provider. Although the exact incidence is unknown, it is probably more common in children than in adults due to the high incidence of colds in children.

Chronic sinusitis is much less common than acute sinusitis. Although any healthy child can develop chronic sinusitis, exposure to year-round allergens and persistent irritants seems to increase the risk. Chronic sinusitis is found in almost all patients with cystic fibrosis, immotile cilia syndrome, or immune disorders.


What are the common findings?

Acute sinusitis can show up with either persistent (the most common form) or severe symptoms. Patients with persistent symptoms of acute sinusitis are differentiated from patients with simple colds solely on the basis of the duration of the symptoms. A simple cold usually lasts 5 to 7 days, and, even if symptoms linger, there should be improvement by 10 days. Cold symptoms that show no improvement after 10 days may be acute bacterial sinusitis.

The symptoms of cold viruses are indistinguishable from acute bacterial sinusitis. They usually include either nasal discharge (thin or thick; white, yellow, or green) or a cough (dry or wet) during both the day and the night. Some children also have bad breath, and/or swelling and darkening around the eyes. Complaints of a headache and facial pain are unusual until adolescence.

The second, less common appearance of acute sinusitis is a cold that seems more "severe" than usual. The severity is defined by the combination of a high fever (higher than 102oF) and thick white, yellow, or green nasal discharge, both of which persist for at least four days. In contrast, a simple cold may or may not have a fever; if a fever is present, it usually is present only for the first day of the symptoms. Patients with severe symptoms may have a headache or facial pain.

Chronic sinusitis is characterized by long-term nasal symptoms and/or a cough. The nasal symptoms may include a runny nose, post-nasal drainage, and/or congestion. When nasal discharge is present, it may be any color or thickness. In some patients, post-nasal drainage is the dominant symptom, leading to a cough or frequent throat clearing. Other patients develop persistent nasal congestion, leading to chronic mouth breathing and frequent complaints of a sore throat. Patients with chronic sinusitis also may complain of fatigue, nausea or vomiting (related to post-nasal drainage), decreased appetite, and impaired sleep.

In young patients with either acute or chronic sinusitis, physical examinations are rarely helpful. A physical examination is most helpful in identifying serious conditions that may make a patient more susceptible to sinusitis. For example, patients with cystic fibrosis tend to have poor growth, clubbing of the fingers, a barrel chest, respiratory findings, and nasal polyps.

Patients with immotile cilia may have respiratory findings, and about 50% of them will have situs inversus, i.e., the heart is on the right side of the body (called Kartageners syndrome). Patients with immune disorders may lack tonsillar tissue and other lymph nodes, and have poor growth, clubbing of the fingers, and other signs of infection.


How is sinusitis diagnosed?

It is important to recognize the similarity of the symptoms between acute sinusitis and simple colds, and not to over-diagnose colds as acute bacterial sinusitis. For the vast majority of patients, a diagnosis of either acute or chronic sinusitis will be based on the symptoms and their duration. Confirmation of the diagnosis by x-ray or CT images of the sinuses should be reserved for those patients who appear to have complications of sinusitis or non-typical symptoms.

Imaging studies must be used carefully, because even patients with common colds can have abnormal images of the sinuses. In general, imaging studies are the most helpful when they are normal and can be used to eliminate the diagnosis of sinusitis.


How is sinusitis treated?

In a joint publication, the Centers for Disease Control (CDC) and the American Academy of Pediatrics (AAP) outlined that "judicious antimicrobial therapy for bacterial sinusitis depends on limiting the use of these agents to children who have a high likelihood of benefiting from treatment."

Amoxicillin is the antibiotic of choice for most patients with acute bacterial sinusitis because of its effectiveness, safety, and low cost. Although amoxicillin is the preferred first-line therapy for acute sinusitis, a more powerful antibiotic may be appropriate in the following situations:

  • A failure to respond to amoxicillin after two to three days of therapy
  • The use of other antibiotic therapy in the last 30 days
  • A high prevalence of antibiotic resistance in the community
  • The appearance of severe sinusitis
  • The possibility of sinusitis with complications
  • The presence of chronic sinusitis

Alternatives to amoxicillin include amoxicillin plus amoxicillin-clavulanate (Augmentin) or an oral cephalosporin. For most patients with acute bacterial sinusitis, the duration of antibiotic therapy should be 10 to 14 days.

In patients with chronic sinusitis, antibiotic therapy is controversial. Patients who do not improve with second-line antibiotics probably do not have an infection as the cause of their chronic symptoms and should not be retreated. If antibiotics have not been used in a patient with chronic sinusitis, it may be reasonable to consider one treatment course with a second-line antibiotic. Antibiotic therapy in patients with chronic sinusitis probably should be limited to three weeks; however, there are no data regarding the optimal duration of therapy for these patients.

Potential therapies that may be used in conjunction with antibiotics for acute and chronic sinusitis include saline sprays, topical intranasal steroids, antihistamines, and topical and oral decongestants. However, there are no studies that have examined systematically these therapies in patients with either acute or chronic sinusitis. Patients with underlying allergic disease are the most likely to benefit from antihistamines and topical nasal steroid sprays. Anecdotal experience suggests that some patients with chronic sinusitis benefit from daily nasal irrigation with saline.

Saline nasal washes are safe, inexpensive, and probably worth a try in these patients. Topical or oral decongestants can relieve pain and obstruction in some patients. Topical decongestants have a potential to be addictive, and their use should be limited to three to five days.


What are the complications?

Complications of sinusitis, which are rare in children, involve the spread of infection to nearby structures, including the eye, the facial and the skull bones, and the brain. Infection of the eye-the most common complication-causes redness of the eyelids, limitation in eye movement, bulging of the eye, and a loss or impairment of vision. Infection that spreads into the bony structures surrounding the sinuses causes obvious swelling and tenderness over the infected bone.

Infection can spread to the brain or the meninges (membrane around the brain). Any patient with a deep-seated headache, pain with eye movement, neck stiffness, a change in vision, localized swelling, or toxic appearance should be evaluated for potential complications of sinusitis.


How can sinusitis be prevented?

The prevention of sinusitis is difficult. Episodes of it can be prevented if the number of upper respiratory infections can be reduced. For children, reducing colds can be accomplished by removing them from the daycare setting or, at least, finding a smaller daycare program. Strict hand washing at home and in daycare settings helps to prevent the spread of upper respiratory infections. Decreasing exposures to known allergens and irritants should help patients with either recurrent acute or chronic sinusitis.

If hypersensitivity to allergens is found, topical intranasal steroid medications are helpful. A two- to four-week treatment trial of topical nasal steroids may be worthwhile even if allergen sensitivity is not found.


What research is being done?

The role of antibiotics in treating acute and chronic sinusitis continues to be investigated. The optimal length of antibiotic therapy is being studied in patients with acute sinusitis. The need for antibiotics is being questioned in patients with chronic sinusitis.

Other research is examining the role of therapies, such as saline sprays, hot steam mists, and topical nasal steroids, in patients with either acute or chronic sinusitis. The mechanism by which our bodies suppress or promote the inflammatory process associated with sinusitis also is being studied. Medications that support the ability of the body (or the sinuses) to regulate this inflammatory process are a possibility in the future.



Spector SL, Bernstein IL, Li JT, et al., eds. Parameters for the management of sinusitis. J Allergy Clin Immunol 1998;102:S117-44.

Wald ER. Diagnosis and management of sinusitis in children. Sem Pediatr Infect Dis 1998;9:4-11.

Wald ER. Chronic sinusitis in children. J Pediatr 1995;127:339-47.

About the Author

Dr. Nash is a pediatric allergist/immunologist practicing at Children's Hospital of Pittsburgh. He divides his time evenly between clinical care and research. He has both research and clinical care interests in the management of children with either sinusitis or asthma.

Dr. Wald received her Bachelor of Science degree at Brooklyn College and her Medical Degree at Downstate Medical Center. She is currently on staff at Children's Hospital of Pittsburgh and specializes in Allergy, Immunology and Infectious Diseases. One of her recent honors includes being named "Pennsylvania Pediatrician of the Year" by the American Academy of Pediatrics.

Copyright 2012 David Nash, M.D., All Rights Reserved