Acute sinusitis is usually precipitated by an earlier upper respiratory tract infection, generally of viral origin.Acute episodes of sinusitis can also result from fungal invasion. These infections are most often seen in patients with diabetes or other immune deficiencies and can be fatal.Chronic sinusitis is a complex spectrum of diseases that share chronic swelling of the sinuses in common. It is divided into cases with polyps and cases without, and the former is sometimes called chronic hyperplastic sinusitis. The factors are not understood and may include allergy, environmental factors such as dust or pollution, bacterial infection, or fungus (either allergic, infective, or reactive). Non allergic factors such as vasomotor rhinitis can also cause chronic sinus problems. Rarely narrow sinus passages, which can delay drainage from the sinus cavities could also be a factor. A combination of anaerobic and aerobic bacteria are observed, including Staphylococcus aureus and coagulase-negative Staphylococci. As a matter of fact antibiotics provide only a temporary benefit, although mechanisms involving hyperresponsiveness to bacteria have been proposed for sinusitis with polyps. Most





include: nasal congestion, facial pain, headache, fever, general malaise, thick green or yellow discharge, vertigo or lightheadedness, blurred vision, feeling of facial 'fullness' or 'tightness' which worsens on bending over, aching teeth, and halitosis. Very rarely, chronic sinusitis can lead to Anosmia, the inability to smell or detect odors.In a few number of cases, chronic maxillary sinusitis can also be brought on by the spreading of bacteria from a dental infection.

Headache/facial pain or pressure of a dull, constant, or aching sort over the affected sinuses can be seen with either acute or chronic stages of sinusitis. This pain is typically localized to the involved sinus and may worsen when the affected person bends over or when in the supine position.