Sinusitis refers to inflammation of the sinuses that occurs with a viral, bacterial, or fungal infection.
Acute sinusitis; Sinus infection; Sinusitis - acute; Sinusitis - chronic; Rhinosinusitis
Causes, incidence, and risk factors
The sinuses are air-filled spaces in the skull (behind the forehead, nasal bones, cheeks, and eyes) that are lined with mucus membranes. Healthy sinuses contain no bacteria or other germs. Usually, mucus is able to drain out and air is able to circulate.
When the sinus openings become blocked or too much mucus builds up, bacteria and other germs can grow more easily.
Sinusitis can occur from one of these conditions:
- Small hairs (cilia) in the sinuses, which help move mucus out, do not work properly due to some medical conditions.
- Colds and allergies may cause too much mucus to be made or block the opening of the sinuses.
- A deviated nasal septum, nasal bone spur, or
nasal polypsmay block the opening of the sinuses.
Sinusitis can be:
- Acute -- symptoms last up to 4 weeks
- Sub-acute -- symptoms last 4 - 12 weeks
- Chronic -- symptoms last 3 months or longer
Acute sinusitis is usually caused by a bacterial infection in the sinuses that results from an upper respiratory tract infection. Chronic sinusitis refers to long-term swelling and inflammation of the sinuses that may be caused by bacteria or a fungus.
The following may increase your risk or your child's risk of developing sinusitis:
Allergic rhinitisor hay fever Cystic fibrosis
- Day care
- Diseases that prevent the cilia from working properly, such as Kartagener syndrome and immotile cilia syndrome.
- Changes in altitude (flying or scuba diving)
- Tooth infections (rare)
- Weakened immune system from
Review Date: 04/18/2010
Reviewed By: Seth Schwartz, MD, MPH, Otolaryngologist, Virginia Mason Medical Center, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.