Individuals with sinusitis have inflamed paranasal sinuses, which are the cavities behind the face that produce the mucus in the nasal passages.

Sinusitis may be acute or chronic (lasting more than 12 weeks), and may be caused by bacteria, fungi, allergies, viruses or an autoimmune reaction.

Sinusitis usually resolves without medical intervention. A doctor’s appointment is strongly recommended if symptoms last more than seven to ten days.

What are Sinuses?

A sinus is a hollow space in the body and the paranasal sinuses are the spaces behind the face that lead to the nasal cavity and produce the same mucous membrane lining as the nose. Mucus helps trap dirt particles and germs and keeps the nasal passages moist.

Mucus buildup and sinus inflammation leads to sinusitis, a condition also referred to as rhinosinusitis.


Symptoms of Sinusitis

Signs of the condition include:

  • Facial pain and pressure
  • Nasal discharge
  • Congestion
  • Cough
  • Reduced sense of smell
  • Blocked nose

Patients with two or more of these symptoms and thick green or yellow nasal discharge may have acute sinusitis.

Serious cases of sinusitis may have the following symptoms:

  • Fever
  • Toothache
  • Headache
  • Tiredness
  • Halitosis, or foul-smelling breath

If symptoms last for 12 weeks or longer, the patient likely has chronic sinusitis.

Types of Sinusitis

There are three types of sinusitis: acute sinusitis, subacute sinusitis and chronic sinusitis.

Acute sinusitis lasts up to four weeks and is the most common type of sinusitis. Symptoms of subacute sinusitis last between four and 12 weeks. If symptoms persist or return after 12 weeks, patients may need more invasive treatment, such as surgery, to treat chronic sinusitis.

Causes of Sinusitis

Sinusitis may be caused by the following:

  • Virus. 90% of sinusitis cases in adults are caused by a virus.
  • Bacteria. 10% of sinusitis cases in adults are caused by bacteria.
  • Pollutant. Airborne irritants or chemicals may trigger a buildup of mucus.
  • Fungi. The sinuses may react to fungi in the air, known as allergic fungal sinusitis (AFS). Sinuses that are invaded by fungi are called chronic indolent sinusitis.

Risk Factors of Sinusitis

Individuals may be at greater risk of developing sinusitis if the following factors apply to them:

  • Previous respiratory tract infections, such as the common cold
  • Weak immune system due to a health condition or medical treatment
  • Nasal polyps, or small growths in the nasal passage, that may cause inflammation
  • Allergic reaction to dust, pollen, animal hair or other allergens
  • Abnormal structure of the nose, such as a deviated septum

Diagnosing Sinusitis

A sinusitis diagnosis usually only requires a simple physical examination. The physician may use a light source to examine the nasal cavity or an otoscope to examine the ears. Patients may be referred to an ear, nose, and throat specialist (ENT) for a more in-depth examination and specialized treatment. An endoscope may be inserted into the nose to provide more detailed images.

Treatment Options

Chronic sinusitis may be treated with antifungal drugs, corticosteroid sprays, allergy medication or surgery. Surgery may be necessary to correct a deviated septum or address polyps.