Sinusitis Q&A

Lori Lemonnier, MD

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What are the sinuses?
What is sinusitis?
How common is sinusitis?
What causes sinusitis?
How can sinusitis be diagnosed?
How can sinusitis be treated?
Who treats sinusitis?
When is surgery needed?

What are the sinuses?
The paranasal sinuses are air filled structures within the bony facial skeleton, located adjacent to the nasal cavity. There are four paired paranasal sinuses, eight in total: 2 maxillary, 2 ethmoid, 2 sphenoid, and 2 frontal sinuses. The bony cavities are lined with soft tissue called mucosa.

What is sinusitis?
Sinusitis is an inflammatory condition of the mucosa of the paranasal sinuses that results in symptoms such as thickened nasal drainage, nasal obstruction and facial pain or pressure.

Viruses, bacteria, and nasal allergies are common causes of inflammation. The inflamed, swollen mucosa of the nasal and sinus cavities leads to obstruction of the openings of the sinuses, or ostia. Unable to circulate air and eliminate the secretions that are produced, the sinuses then become an ideal environment for bacterial infection. Because sinusitis is often preceded by, and almost always accompanied by, inflammation of the nasal mucosa (rhinitis), the term "rhinosinusitis" is used by otolaryngologists to replace the term "sinusitis".

Rhinosinusitis is categorized into types according to the duration of symptoms:

  • Acute - symptoms are present for 4 weeks or less
  • Subacute - symptoms are present for more than 4 weeks, but less than 12 weeks
  • Chronic - symptoms are present for 12 weeks or greater
  • Recurrent acute - 4 or more acute episodes occurring within 1 year, with resolution of symptoms between episodes
  • Acute exacerbation of chronic rhinosinusitis - an acute episode occurring in a patient with chronic rhinosinusitis, producing a sudden worsening of baseline symptoms

How common is sinusitis?
In the United States, more than 30 million people are diagnosed with sinusitis each year. Moreover, chronic rhinosinusitis effects approximately 15% of the U.S. population and is one of the most common chronic illnesses in America.

What causes sinusitis?
The central event in sinusitis is blockage of the sinus openings, or ostia as a result of inflammation. Causes of sinonasal inflammation include:
  • Viruses
  • Bacteria
  • Fungus
  • Nasal allergy
  • Reactive airway disease, such as Asthma and Samter’s triad
  • Congenital diseases, such as Cystic Fibrosis
  • Inflammatory diseases, such as Sarcoidosis and Wegener’s Granulomatosis
  • Immunodeficiencies, such as AIDS
  • Previous surgery, resulting in scar tissue formation
  • Trauma, resulting in facial fractures

Unable to circulate air and eliminate the secretions that are produced, obstructed sinuses then become an ideal environment for bacterial infection.

Many different types of bacteria can infect the paranasal sinuses. The bacteria most often cultured in acute rhinosinusitis are:
  • Streptococcus pneumoniae
  • Hemophilus pneumoniae
  • Moraxella catarrhalis

In chronic rhinosinusitis, it is not uncommon to find multiple bacteria present in a single culture sample. In addition, these organisms may demonstrate drug resistance, responding to only select antibiotics. Bacteria commonly cultured in chronic rhinosinusitis include:
  • Staphylococcus aureus
  • Gram negative organisms, such as Pseudomonas aeriginosa

How can sinusitis be diagnosed?
The diagnosis of sinusitis, especially chronic sinusitis, can be difficult to make. Physicians rely upon patient history and physical examination to make the diagnosis. Your otolaryngologist will ask questions to determine exactly what symptoms you are experiencing and for how long.

Acute sinusitis is predominately caused by viruses and bacteria. Because viral and bacterial sinusitis are managed differently, it is important to distinguish between the two causes. Both produce thickened, discolored nasal drainage accompanied by the cardinal symptoms of nasal obstruction and/or facial pain/pressure/fullness. Initially, acute sinusitis is considered to be a viral event. According to the most recent clinical practice guidelines, only once symptoms are present for at least 10 days (but less than 4 weeks) is the diagnosis of acute bacterial sinusitis made. Double worsening, a phenomenon in which symptoms initially improve, but then subsequently increase in severity, is also considered diagnostic for acute bacterial sinusitis.

The clinical practice guidelines base the diagnosis of chronic rhinosinusitis (CRS) on a history of greater than 12 weeks of sinonasal signs/symptoms accompanied by evidence of nasal inflammation on examination and/or a CT scan of the paranasal sinuses.

Diagnostic signs and symptoms include:
  • Nasal drainage that is thick and discolored, or purulent
  • Facial pain, pressure, or fullness, that often affects the cheeks, teeth, or area around the eyes
  • Nasal obstruction and/or congestion
  • Decreased sense of smell

Additional symptoms that may be encountered include:
  • Cough
  • Post nasal drip
  • Bad breath or halitosis
  • Headache
  • Ear pain, pressure, or fullness

If two or more signs/symptoms are present for a duration of 12 weeks or more, and evidence of inflammation is encountered on examination and/or CT scan, a diagnosis of CRS is made. Physical examination may be performed with a nasal speculum or nasal endoscope, depending on the severity of findings. Nasal endoscopes are thin telescopes designed to examine the nasal cavity and ostia of the paranasal sinuses. If purulent secretions are present, a culture can be taken to identify the causative organism(s). Inflammation is evidenced by findings of:
  • Thickened, purulent secretions
  • Edematous, swollen nasal mucosa
  • Red, erythematous nasal mucosa
  • Nasal polyps

A CT scan of the paranasal sinuses is typically ordered if medical therapy fails to improve the above signs/symptoms. CT scans provide details of the bony anatomy of the sinuses and are able to demonstrate thickening or abnormalities of the nasal and sinus mucosa.

How can sinusitis be treated?
Much like the common cold, acute viral sinusitis resolves without treatment. Because viruses do not respond to antibiotic therapy, viral sinusitis is primarily managed with supportive care such as nasal saline rinses. Medications, including antihistamines, decongestants and pain relievers may be offered by your physician to help decrease the severity of your symptoms.

The mainstay of treatment for acute bacterial sinusitis is an appropriate antibiotic. Your physician will base the choice of antibiotics on many factors, including:
  • The most likely type of bacteria causing the infection
  • Potential resistance of the bacteria to certain antibiotics
  • Results of sinus cultures, if they are available
  • Patient allergies
  • Other medications that the patient is also taking
  • The patient's other medical conditions
  • Previous treatment

The physician will consider each of these factors prior to choosing an antibiotic. The duration of treatment is typically between 10-14 days. Pain relief should also be provided with either over the counter or prescription medications. As with acute viral sinusitis, additional medications, such as steroids, antihistamines, decongestants and mucolytics may be offered by your physician to help decrease the severity and duration of your symptoms. Nasal saline rinses are also often recommended.

Because of the vast number of underlying, often multiple, causes, the treatment of chronic rhinosinusitis becomes more complicated. In general, however, CRS requires more prolonged durations of medical therapy. Antibiotics, when required, are often based on the results of sinonasal cultures and prescribed for 3-4 weeks time.

Who treats sinusitis?
Primary care physicians, family practitioners, internists, allergists and pulmonologists are all involved in the medical treatment of sinusitis. However, patients suffering from symptoms of recurrent acute or chronic rhinosinusitis are often referred to an otolaryngologist. Otolaryngologists, or ENT physicians, are specialists providing both medical and surgical treatment of disorders or the ears, nose and throat.

Some otolaryngologists choose to further subspecialize in rhinology; the management of diseases of the nose and paranasal sinuses. Patients with severe or complicated disease and those requiring revision surgery are often referred to rhinologists for evaluation and management.

When is surgery needed?
Sinus surgery is performed for chronic rhinosinusitis that does not resolve with medical treatment. It must be remembered that sinusitis is primarily a medical disease that needs to be treated aggressively with medication before considering surgery. Even after successful sinus surgery, many patients with CRS will continue to require medication to control the underlying cause(s) of inflammation and prevent the return of symptoms.

For patients who continue to have symptoms despite appropriate medical treatment, sinus surgery is an excellent option. Today, this surgery is typically performed using the principles of functional endoscopic sinus surgery (FESS). The goal of FESS is to restore normal function to the blocked sinuses. During a FESS procedure, the surgeon locates and enlarges the small natural drainage passageways of the sinuses. The entire operation is performed through the nostril using the nasal endoscope, with external incisions through the facial skin very rarely being required.

Sinus infections are capable of spread to adjacent structures outside of the sinus cavities, such as the eye and brain. Such complications are quite rare, but considered medical and surgical emergencies, requiring immediate treatment. Typically, surgery will be required to drain the collection of infection and enlarge the ostia of the responsible sinuses.

Clinical practice guideline: Adult sinusitis. Richard M. Rosenfeld, et al. Otolaryngology -- Head and Neck Surgery 2007 137: S1

Revised 9/2011
©American Rhinologic Society