Sinusitis is defined as a condition manifested by inflammation of the mucous membranes of the nasal cavity and Para nasal sinuses, fluids within these cavities, and/or the underlying bone.

Clinical features of Sinusitis
The patient may complain of facial pain and a pus discharge from the nose. If the condition is acute the patient may have fever. The patients complain of a sense of nasal obstruction and a decreased sense of smell. They usually complain of headache also.

Diagnosis	Duration
Acute sinusitis	Four or fewer weeks in duration.
Chronic sinusitis	More than four weeks in duration.
Recurrent acute sinusitis	Four or more episodes per year, each episode lasting at least 10 days, without signs of chronic sinusitis between.

Examination reveals swelling and redness of the area around the nose and ear. Looking into the nose with the help of a speculum one may find redness, crust formation, polyps in the nose or even discharge from the nose. A more detailed examination of the nose can be made by doing nasal endoscopy.

Acute, chronic and recurrent sinusitis
Sinusitis can be caused or aggravated by a number of factors. Anatomical abnormalities of the nose like deviated nasal septum, viral infections, environmental dust and pollution, surgery done on the nose, medications, and patients whose immune system is compromised.

Investigations of Sinusitis
Plain X–ray films of the sinus may show pacifications or air-fluid levels, but can appear normal in true sinusitis. Other investigations depend on the clinical situation:

CT scan of the sinuses demonstrates mucosal thickening, polyps, fluid levels in sinuses, as well as underlying anatomical abnormalities predisposing to sinusitis. Further, specific testing may be required to find the underlying cause as the case. Tests are done to evaluate the immune status of the patient, allergic testing if allergic rhinitis is suspected.

Treatment of acute sinusitis:
The mainstay of treatment for acute sinusitis is to treat patients with decongestants and antibiotics. The antibiotics commonly used are Amoxicillin-clavulanate, azithromycin, clarithromycin and cefuroxime. The treatment lasts usually for 14 days.

Nasal decongestants are available for local application or for systemic use. If the attack is severe systemic decongestants are more helpful. Local decongestants should not be used on a long term basis as it can result in local inflammation. It should be noted that many of these cause sedation as a side effect. Steam inhalation to clear the mucous secretions also helps.

Treatment of chronic sinusitis:

• Antibiotics such as clindamycin and metronidazole are used for treatment as they are effective against fighting the bacteria which cause chronic sinusitis.
• If there is an allergic component there could be:
1. Avoidance of allergens.
2. Topical nasal steroids.
3. Antihistamines.
4. Systemic steroids.
5. Immunotherapy.
• Surgery