Sinusitis is the inflammation of one or more of the paranasal sinuses, which may be the result of infection by bacteria, viruses, or fungi, or the result of allergic or autoimmune inflammation. Each year, over 36 million adults and children develop sinusitis.

Nasal sinuses are hollow, air-filled cavities within the cheek bones that are lined with mucous membranes. Each of the four pairs of sinuses is connected to the nose in order to allowing mucus to drain and air to circulate. The primary function of these sinuses is to warm, moisten, and filter the inspired air. Healthy sinuses are sterile, meaning that they are devoid of bacteria, viruses, or other infectious agents.

 What are the types of sinusitis?

Sinusitis can be divided into the following categories: acute, in which symptoms last less than four weeks; sub-acute, with symptoms lasting from 4 to 8 weeks; chronic sinusitis, with symptoms that last eight weeks or longer. Recurrent sinusitis is characterized by three or more episodes of acute sinusitis per year.

What are the symptoms of sinusitis?

Acute sinusitis usually presents with symptoms of a common cold that do not seem to improve after 7-10 days. These symptoms may include:

• Nasal congestion and discharge

• Sore throat and postnasal drip (fluid dripping down the back of your throat, especially at night or when you lie down)

• Headache -- pressure-like pain behind the eyes, toothache, or facial tenderness

• Cough, often worse at night

• Fever (may be present)

• Bad breath

• Fatigue and generally not feeling well

Symptoms of chronic sinusitis may be the same as acute sinusitis, but tend to be milder and more subtle. They may include chronic nasal congestion, post-nasal drip, loss of smell and taste, and a cough.

What are some possible causes of sinusitis?

Infection of the sinuses usually starts with a viral upper respiratory infection, commonly known as the common cold. The cold virus can cause damage to the lining of the sinus, predisposing the tissues to colonization with bacteria, a virus, or fungal spores. When infected by a pathogen or inflamed by allergies, the sinuses may become blocked with mucus or by swelling of the mucosal lining. In addition, if the small hairs, or cilia, located in the lining of the sinuses are not working properly, the mucus will not be efficiently removed from the sinuses, resulting in mucus accumulation and thickening, with resultant sinusitis.

Although viral upper respiratory infections are the most common cause of acute sinusitis, people with uncontrolled allergies have a higher likelihood of developing sinusitis. Allergies trigger inflammation of the nose and lining of the sinuses, resulting in swelling and obstruction of the mucus flow patterns. This inflammation also prevents the sinus cavities from clearing out bacteria, and increases the chances of developing secondary bacterial sinusitis.

Patients with chronic sinusitis should be evaluated for structural problems in the nose. Narrow drainage passages, polyps, tumors, or a severe deviated nasal septum may predispose to one developing sinusitis. Surgical intervention is sometimes needed to correct these problems.

How does you doctor diagnose a sinus infection?

Most cases of acute sinusitis can be diagnosed clinically, without the need for laboratory tests or x-rays. However, a simple sinus x-ray can confirm the diagnosis.

To make a diagnosis of chronic sinusitis, a physician will often need to take a detailed history and perform a physical examination. The physician will likely need to order imaging studies including a CT scan (which makes multiple precise images of the sinus cavities), or an MRI. A sampling of the nasal secretions or lining can sometimes be helpful in identifying the causative infective agent. Allergy testing may also be indicated when trying to identify an underlying predisposition to recurrent or chronic sinusitis.

As part of a complete examination, it may also be necessary to directly visualize the area where the sinuses and middle ear drain into the nose. This endoscopic examination is a simple and quick office procedure which involves inserting a narrow, flexible fiberoptic scope into the nasal cavity through the nostrils.

What are the most common treatment options?

The treatment of both acute and chronic sinusitis generally requires a combination of therapies, with the goals of eliminating infection, reducing swelling and inflammation, and promoting drainage. In addition to prescribing an antibiotic when it is suspected that the sinusitis is caused by bacteria, your physician may prescribe a medication to reduce blockage or control allergies. This is critical step to keeping the sinus passages open and promoting drainage. This medicine may be a decongestant, an expectorant  (mucus-thinning medicine), or a cortisone nasal spray. A short course of five days or less of a decongestant nose spray can be extremely helpful in keeping the nasal passages open, especially in acute sinusitis. Oral or injectable steroids are sometimes prescribed to reduce the inflammation in the mucosal lining of the sinuses, therefore enhancing drainage. The treatment of sinusitis can often be augmented by nasal irrigations with a buffered saline (salt water) solution. Breathing in hot, moist air can also help liquefy the sinus contents to promote drainage.

Allergic individuals may require long-term treatment to control and reduce nasal and sinus inflammation in order to prevent the development of sinusitis. This treatment may include environmental control measures to reduce exposure to allergens, the use of medicine to minimize allergic inflammation, and/or immunotherapy. Patients with vasomotor or non-allergic rhinitis are also at a higher risk for sinusitis due to chronic airway inflammation. Besides using anti-inflammatory nose sprays, these individuals should avoid environmental irritants such as tobacco smoke and strong odors, which may increase symptoms.

Consultation with an ear, nose, and throat physician may be necessary for recurrent or difficult to treat chronic sinusitis. One or more obstructed and infected sinuses which does not respond to aggressive medical therapy may require surgical intervention.