Nasal polyps are pale, edematous, mucosally covered masses commonly seen in patients with allergic rhinitis. They may result in chronic nasal obstruction and a diminished sense of smell. In patients with nasal polyps and a history of asthma, aspirin should be avoided as it may precipitate a severe episode of bronchospasm, known as triad asthma (Samter triad). Such patients may have an immunologic salicylate sensitivity.
Nasal polyps grow in inflamed tissue of the nasal mucosa. The mucosa is a very wet layer that helps protect the inside of your nose and sinuses and humidifies the air you breathe. During an infection or allergy-induced irritation, the nasal mucosa becomes swollen and red, and it may produce fluid that drips out. With prolonged irritation, the mucosa may form a polyp. A polyp is a round growth (like a small cyst) that can block nasal passages.
Although some people can develop polyps with no previous nasal problems, there’s often a trigger for developing polyps. These triggers include:
- chronic or recurring sinus infections
- allergic rhinitis (hay fever)
- cystic fibrosis
- Churg-Strauss syndrome
- sensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or aspirin
There may be a hereditary tendency for some people to develop polyps. This may be due to the way their genes cause their mucosa to react to inflammation.
Nasal polyps are associated with irritation and swelling (inflammation) of the lining of your nasal passages and sinuses that lasts more than 12 weeks (chronic sinusitis).
However, it’s possible to have chronic sinusitis without nasal polyps.
Nasal polyps themselves are soft and lack sensation, so if they’re small, you may not be aware you have them. Multiple growths or a large polyp may block your nasal passages and sinuses.
Common signs and symptoms of chronic sinusitis with nasal polyps include:
- A runny nose
- Persistent stuffiness
- Postnasal drip
- Decreased or absent sense of smell
- Loss of sense of taste
- Facial pain or headache
- Pain in your upper teeth
- A sense of pressure over your forehead and face
- Frequent nosebleeds
Your doctor can usually make a diagnosis based on your answers to questions about your symptoms, a general physical exam and an examination of your nose. Polyps may be visible with the aid of a simple lighted instrument.
Other diagnostic tests include:
- Nasal endoscopy. A narrow tube with a lighted magnifying lens or tiny camera (nasal endoscope) enables your doctor to perform a detailed examination inside your nose and sinuses.
- Imaging studies. Images obtained with computerized tomography (CT) can help your doctor pinpoint the size and location of polyps in deeper areas of your sinuses and evaluate the extent of swelling and irritation (inflammation).
These studies may also help your doctor rule out other possible blockages in your nasal cavity, such as structural abnormalities or another type of cancerous or noncancerous growth.
- Allergy tests. Your doctor may suggest skin tests to determine if allergies are contributing to chronic inflammation. With a skin prick test, tiny drops of allergy-causing agents (allergens) are pricked into the skin of your forearm or upper back. Your doctor or nurse then observes your skin for signs of allergic reactions.
If a skin test can’t be performed, your doctor may order a blood test that screens for specific antibodies to various allergens.
- Test for cystic fibrosis. If you have a child diagnosed with nasal polyps, your doctor may suggest testing for cystic fibrosis, an inherited condition affecting the glands that produce mucus, tears, sweat, saliva and digestive juices.
The standard diagnostic test for cystic fibrosis is a noninvasive sweat test, which determines whether your child’s perspiration is saltier than most people’s sweat is.
- Blood test. Your doctor may test your blood for low levels of vitamin D, which are associated with nasal polyps.
Use of topical intranasal corticosteroids improves the quality of life in patients with nasal polyposis and chronic rhinosinusitis. Initial treatment with topical nasal corticosteroids for 1–3 months is usually successful for small polyps and may reduce the need for operation.
A short course of oral corticosteroids (eg, prednisone, 6-day course using 21 [5-mg] tablets: 6 tablets [30 mg] on day 1 and tapering by 1 tablet [5 mg] each day) may also be of benefit. When polyps are massive or medical management is unsuccessful, polyps may be removed surgically.
In healthy persons, this is a minor outpatient procedure. In recurrent cases or when surgery itself is associated with increased risk (such as in patients with asthma), a more complete procedure, such as ethmoidectomy, may be advisable.
In recurrent polyposis, it may be necessary to remove polyps from the ethmoid, sphenoid, and maxillary sinuses to provide longer-lasting relief. Intranasal corticosteroids should be continued following polyp removal to prevent recurrence, and the clinician should consider allergen testing to determine the offending allergen and avoidance measures.
Biologic therapies with interleukin-specific blocking antibodies are currently in preclinical and clinical trials and may be a valuable means of controlling nasal mucosal polyps in the future.