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,
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
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
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
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
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
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