Underlying the pathophysiology of sinus disease is a disturbance of the mucus lining in and around the opening of the various facial sinuses. Frequently, there are predisposing factors which contribute to inflammation of the nasal mucous membranes and the mucous membranes in these openings to the sinuses. These include acute viral illnesses, allergic nasal disease, nasal polyps, foreign bodies, infected materials such as infected water contracted during swimming or diving, and certain anatomic abnormalities such as deviated nasal septum or the immotile cilia syndrome, which is a congenital disorder involving abnormal function of the small nasal cilia which move mucus and debris out of the nose. Nasal allergy is frequently associated with sinus disease, since the allergic reaction increases nasal mucus production and causes nasal mucosal swelling and obstruction. Generally, sinusitis can be classified by duration of the problem.
Acute sinusitis is any infectious process in the sinus lasting from one day to three weeks.
Subacute sinusitis is a sinus infection or inflammation lingering from three weeks to approximately three months, and the chronic sinusitis is sinus infection or inflammation persisting for longer than three months. Symptoms of sinusitis relate to the location of the sinus involved and whether the individual is suffering from acute, subacute or chronic sinusitis. The most frequent symptoms of acute sinusitis include pain, nasal obstruction nasal discharge, fever and generalized malaise and lethargy. Pain is usually over the area of the infected sinus , and frequently nasal discharge is yellow to green in appearance. Previous upper respiratory tract viral infections are frequent predisposing factors to the development of acute or chronic sinusitis.