Acute & Chronic Sinusitis – Causes, Diagnosis, Treatment

Sinusitis is an inflammation or irritation of the mucous membrane lining the sinus cavities. Sinusitis may be considered as acute if it lasts for less than 4 weeks, sub-acute if present for 4 to 12 weeks or chronic if it persists for over 12 weeks. Sinusitis should not be confused with hay fever, or allergic rhinitis, which is a condition causing a runny nose, bouts of sneezing and other allergy related symptoms.

Sinuses are the air chambers in the skull behind our cheeks, eyebrows and jaws. Each sinus has an opening into the nose for the free exchange of air and mucus. Sinuses are joined with the nasal passages by a continuous membrane lining it and is kept moist by mucus. The function of the sinuses is to help protect the airways by trapping irritants that are taken in during breathing. Sinus cavities also improve the quality of the voice.

Causes of Sinusitis

There are many causes for this sinusitis, often the same factors that will cause other upper respiratory tract conditions.

  • Common cold or flu (influenza)
  • Infections of the nose or sinuses by bacteria, viruses or fungi
  • Allergies
  • Deviated septum -when the partition between the nose is crooked and can cause swelling of the nasal and sinus passages and lead to sinusitis.
  • Smoking or breathing in smoke (secondary smoke inhalation) interferes with the function of sinus leading to infection.
  • Some people have growths called nasal polyps that block their sinus passages.
  • Very young children may be prone to developing sinusitis because their smaller sinus passages become obstructed more easily than those of adults.
  • Damp weather or pollutants in the air and in buildings also can trigger sinusitis.
  • Drinking alcohol also causes nasal and sinus membranes to swell.
  • Asthma sufferers may have frequent episodes of acute sinusitis.

Signs and Symptoms of Sinusitis

Some general symptoms of all sinusitis include a blocked nose, thick nasal discharge, reduced sense of smell, cough, fever & tiredness.

The sinuses are divided into 4 groups, so the symptoms of sinusitis vary, depending on which group is affected:

  • The frontal sinuses are on either side of the forehead, above the eyes. When inflamed, they cause pain & tenderness above the eyebrows.
  • The ethmoid sinuses are between the eyes. Inflammation causes pain around & between the eyes & on the sides of the nose.
  • The maxillary sinuses are located in the cheekbones. They are the largest & most commonly affected. Sinusitis causes pain in the upper jaw, teeth & cheeks. It can often be mistaken for a toothache.
  • The sphenoid sinuses are behind the eyes. Inflammation causes pain behind the eyes, earache & neck pain.

Diagnosis of Sinusitis

The diagnosis of sinusitis can often be suspected based on the signs & symptoms & after a complete medical and physical evaluation. Various tests can help confirm the diagnosis. The diagnosis is typically made by looking inside the nose with a flexible rubber tube called an endoscope. X-rays of the sinuses can show the thickening of the membrane lining in the sinuses.

Rhinoscopy, a procedure for directly looking in the back of the nasal passages with a small flexible tube, may be used to directly look at the sinus openings and check for obstruction. It may sometimes be necessary to examine a sample of the membrane of a sinus to confirm the diagnosis of sinusitis and to determine the bacteria causing it.

In severe cases of infection and sinus congestion, your ENT may consider a procedure known as a ‘sinus wash out’.

Treatment of Sinusitis

The treatment of sinusitis is most often based on the relief of the symptoms:

  • Painkillers are given to reduce pain & fever.
  • Decongestants help unblocked the sinuses.
  • An antihistamine is used for sinusitis that is caused by an allergy (dust, pollen etc).
  • Steroid nasal sprays to reduce inflammation. Salt water or saline sprays are also often used.
  • If there is a bacterial infection involved, antibiotics are prescribed.