Sinusitis

What are Sinuses?

The sinuses are air-filled spaces located in the skull. The four pairs of paranasal sinuses, connecting to the nasal passage, include:

• The frontal sinuses (in the forehead)
• The maxillary sinuses (behind the cheekbones)
• The ethmoid sinuses (between the eyes), and
• The sphenoid sinuses (behind the eyes).

Lining the sinuses are membranes that secrete mucous, which entraps bacteria and absorbs pollutants, and drain into the nasal passage. In healthy sinuses, the mucous membranes are intact, the sinus passages are open enough to allow drainage and air circulation through the nasal passage, and cilia (small, hair-like projections) propel the mucous outward.

What is Sinusitis?

Sinusitis is an infection that may be caused by one or more problems with the normal functioning of the sinuses. Various conditions may impair the flow of air through the nasal passage, obstruct the sinuses, or cause the mucous to thicken and become stagnated. If secretions are prevented from draining and air flow is blocked, then certain bacteria easily grow in the sinuses, causing infection, swelling, and inflammation.

Types of Sinusitis

Acute Sinusitis

Acute sinusitis is most commonly triggered by a viral cold or flu that infects the upper respiratory tract and causes congestion and obstruction. Bacteria such as streptococcus pneumonia, H. influenzae, and Moraxella (or Branhamella) catarrhalis are the most common culprits. Less common bacteria include other streptococcal strains, staphylococcus aureus and others. Viruses are implicated in only about 10% of cases. Fungi are an uncommon cause of sinusitis in the US, but are serious and must be treated immediately if detected. People with diabetes and compromised immune systems are at higher than normal risk for acute, invasive fungal sinusitis.

Acute sinusitis may last up to eight weeks, or it may consist of four or fewer recurrent episodes per year, each lasting ten days or less. Acute sinusitis is generally treated with antibiotics, and it causes no residual damage to the mucous membranes.

Chronic Sinusitis

Chronic sinusitis lasts longer than eight weeks in adults or twelve weeks in children. In chronic sinusitis, the mucous membranes usually sustain damage that may be seen through imaging techniques.

Chronic sinusitis may be caused by :

• Structural abnormalities such as polyps, enlarged adenoids, cleft palate, tumors, or a deviated septum.
• Infection. Staphylococcus aureus (commonly called Staph infection) is present in about 20% of cases, although it does not appear to cause sinusitis. Certain anaerobic bacteria (peptostreptococcus, fusobacterium, and prevotella) are also present in the vast majority of cases. It should be noted, however, that bacterial infection is not always present, and persistent inflammation may be caused by other factors.
• Medical problems that cause chronic thickened mucous, such as cystic fibrosis or Kartagener's syndrome.
• Immune disorders such as diabetes, AIDS, or other conditions that predispose patients to sinusitis.

Co-Infections in Children

In children, the same bacteria that cause sinusitis also commonly cause ear and adenoid infections. About half of children with otitis media with effusion (OME) have maxillary sinusitis, and about a quarter of children with sinusitis have OME.

Colds and Flu

The majority of people with colds develop inflamed sinuses, most commonly the maxillary sinuses (behind the cheek bones), although the other paranasal sinuses become inflamed as well in a third of patients. Such inflammation is usually brief, mild, and does not develop into true sinusitis.

Other conditions associated with Sinusitis

Sinusitis is strongly associated with asthma and allergic rhinitis, with patients often suffering from more than one of these conditions. Exposure to secondhand smoke increases the risk for sinusitis in asthmatic children even further. Gastroesophageal reflux disease (GERD) is a risk factor for sinusitis and other upper respiratory conditions.

Symptoms of Sinusitis

Sinusitis symptoms depend on the location of the infection; for example, the pain in maxillary sinusitis occurs in the cheeks and may extend to the teeth and mouth, whereas frontal sinusitis causes pain across the lower forehead. Sphenoid sinusitis (behind the eyes) rarely occurs by itself, but may cause pain behind the eyes and even double vision or other visual disturbances.

Symptoms of acute sinusitis may include:

• Nasal congestion and thick, yellow-green discharge
• Severe headache
• Pain or pressure in the face
• Persistent cough
• Fever
• Fatigue
• Sneezing
• Sore throat
• Muscle ache

Symptoms of chronic (or acute recurrent) sinusitis may include:

• Nasal congestion and obstruction
• Yellowish discharge
• Chronic cough
• Bad breath
• Postnasal drip (which may cause sore throat)
• Facial tenderness or pressure

Treatments for Sinusitis

Treatments for sinusitis are aimed at reducing inflammation, eliminating infection, draining the sinuses, and keeping them open. More than half of patients with acute sinusitis recover using home remedies (including hydration and inhalation of steam) and decongestants. Antibiotics may be prescribed in some cases of infection. For chronic sinusitis, antibiotics or steroid nasal sprays (to reduce inflammation) may be prescribed.

If drug therapy fails to unblock the sinuses or if other complications such as structural abnormalities are present, surgery may be required. A drainage tube may be inserted to clear out the sinuses. Endoscopic sinus surgery may be performed to correct obstructions, promote drainage, and aid in healing. In rare cases, invasive surgery using conventional scalpel techniques may be required to remove infected areas.

Information about Enlarged Adenoids  

Anatomy of the Sinuses