Diagnosis

Because your nose can get stuffy when you have a condition like the common cold, you may confuse simple nasal congestion with sinusitis. A cold, however, usually lasts about 7 to 14 days and goes away without treatment. Acute sinusitis often lasts longer and typically causes more symptoms than a cold.

Your healthcare provider can usually diagnose acute sinusitis by noting your symptoms and doing a physical examination, which includes examining your nasal tissues. If your symptoms are vague or persist, your healthcare provider may order a computed tomography (CT) scan, a form of X-ray, to confirm that you have sinusitis.

Laboratory tests your healthcare provider may use to diagnose chronic sinusitis include

• Blood tests to rule out conditions associated with sinusitis, like an immune deficiency disorder
• A sweat test or a blood test to rule out cystic fibrosis
• Tests on the material that is inside your sinuses to detect bacterial or fungal infection
• Biopsy of the membranes (linings) of the nose or sinuses to determine the health of the cells lining these cavities