What Are Nasal Polyps? What Causes Nasal Polyps?

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Main Category: Ear, Nose and Throat
Article Date: 25 Jan 2010 - 0:00 PDT


Nasal polyps (singular: nasal polyp) are fleshy swellings, or polypoidal masses that develop in the lining of the nose and paranasal sinuses (air-filled spaces, communicating with the nasal cavity, within the bones of the skull and face). They are non-cancerous growths.

Polyps vary in size; they may be yellowish brown or pink and are shaped like teardrops. As they grow they eventually look like grapes on a stem.

Polyps usually grow in both nostrils; they can also grow on their own or in clusters. Polyps in just one side of the nose are not common.

Large polyps and/or clusters can cause breathing difficulties. They can affect the patient's sense of smell. They may block the sinuses and cause frequent infections and other problems.

According to the National Health Service (NHS), UK, nasal polyps affect between 1 and 20 people out of every 1,000. They are about four times as common in males as females. People who develop them tend to do so after the age of 40. Individuals with asthma, frequent sinus infections and allergies are more likely to develop nasal polyps. Some children with cystic fibrosis may develop nasal polyps.

According to Medilexicon's medical dictionary:

A nasal polyp is "an inflammatory or allergic polyp, arising from the ostium or cavity of one of the paranasal sinuses, which projects into the nasal cavity."

What are the signs and symptoms of nasal polyps?

A symptom is something the patient feels and reports, while a sign is something other people, such as the doctor detect. For example, pain may be a symptom while a rash may be a sign.

Individuals with nasal polyps tend to have chronic inflammation of the lining of the nasal passages and sinuses (chronic sinusitis). If there are clusters or large polyps the patient's nasal passages and sinuses may be obstructed. People with small nasal polyps may have no signs or symptoms. The following signs and symptoms are typically present:

• Runny nose - this may be permanent, with the patient feeling as if he/she always has a cold.
  
  
• Persistent stuffy or blocked nose - in some cases the patient may find it hard to breathe through the nose. There may be sleeping problems.
  
  
• Postnasal drip - a feeling of mucus continually running down the back of the throat.
  
  
• Either no sense of smell or poor sense of smell - this may not improve after polyps are treated
  
  
• Poor sense of taste - this may not improve after polyps are treated.
  
  
• Pain in the face
  
  
• Headache
  
  
• Snoring
  
  
• Itchiness around the eyes
  
  
• Obstructive sleep apnea - in severe cases. This is a potentially serious condition; the patient stops breathing during sleep.
  
  
• Double vision - in severe cases. More likely to occur if the patient has allergic fungal sinusitis or cystic fibrosis.

What are the risk factors for nasal polyps?

A risk factor is something which increases the likelihood of developing a condition or disease. For example, obesity significantly raises the risk of developing diabetes type 2. Therefore, obesity is a risk factor for diabetes type 2.

Any individual who has a condition that results in chronic inflammation of the nasal passages or chronic sinusitis, as well as people with allergic conditions have a significantly increased risk of developing nasal polyps, examples include:

• Sensitivity to aspirin - people with an allergic response to aspirin or other NSAIDs (non-steroidal anti-inflammatory drugs) are more likely to develop polyps.
  
  
• Asthma - patients who suffer from asthma are more susceptible to developing nasal polyps.
  
  
• Allergic fungal sinusitis - this is an allergy to airborne fungi.
  
  
• Rhinitis - including hay fever.
  
  
• Cystic fibrosis - a chronic disease that affects organs such as the liver, lungs, pancreas, and intestines. It disrupts the body's salt balance, leaving too little salt and water on the outside of cells and causing the thin layer of mucus that usually keeps the lungs free of germs to become thick and sticky. This mucus is difficult to cough out, and it clogs the lungs and airways, leading to infections and damaged lungs.
  
  
• Churg-Strauss syndrome - a disease that results in the inflammation of blood vessels.
  
  
• Age - nasal polyps are more common among adults aged at least 40 years.
  
  
• Genetics - some research has indicated that if your parents have/had nasal polyps your risk of developing them yourself is greater, compared to other people.

What are the causes of nasal polyps?

The pathogenesis of nasal polyps is unknown - the step by step development of a disease and the chain of events leading to that disease. Experts say that nasal polyps are thought to be caused by allergy and also cystic fibrosis (less commonly). A significant number of cases are linked to non-allergic asthma. In some cases no respiratory or allergic trigger is found.

Nasal polyps have no relationship with colonic or uterine polyps.

Nasal polyps are the result of swelling (inflammation) in the nose or sinuses - they are not a disease. Experts say that inflammation causes an accumulation of fluid in the cells of the nose and sinuses. Eventually, gravity pulls these heavy cells down, resulting in polyps. Scientists believe possible triggers are bacterial or viral infection, an allergy, or an immune response to a fungus.

Nasal polyps appear most frequently near the openings to the sinuses (in the nasal passage); however, they can develop anywhere throughout the nasal passages or sinuses.

Diagnosing nasal polyps

A doctor will generally be able to make a diagnosis after receiving answers to some questions regarding symptoms, carrying out a general examination, and more specifically, examining the patient's nose. Often polyps are visible with the aid of a lighted instrument.

The doctor may also order the following tests:

• Nasal endoscopy - an endoscope - a narrow tube with a small camera (or magnifying lens) is inserted into the patients nose.
  
  
• CT (computerized tomography) scan - the CT scanner uses digital geometry processing to generate a 3-dimensional (3-D) image of the inside of an object. The 3-D image is made after many 2-dimensional (2-D) X-ray images are taken around a single axis of rotation - in other words, many pictures of the same area are taken from many angles and then placed together to produce a 3-D image. The device enables the doctor to locate nasal polyps as well as other abnormalities linked to chronic inflammation. The doctor will also be able to identify any other obstructions.
  
  
• Skin prick allergy test - small drops of agents known to cause allergies in some people are pricked into the skin - usually the upper back or the forearm. After 15 minutes the health care professional looks for signs of an allergic reaction. In some cases the doctor may order a blood test which determines whether there are any antibodies linked to various allergens.
  
  
• Cystic fibrosis - if the patient is a young child the doctor may order a cystic fibrosis test. This test measures the amount of sodium and chloride in the child's sweat.

What are the treatment options for nasal polyps?

Steroids - the doctor may prescribe a steroid spray or nose drops. This medication shrinks the polyps and reduces inflammation. This treatment is more common for patients with one or more small polyps. The patient should feel the beneficial effects within a week - with some of the newer steroid sprays this may take longer. Steroid sprays/drops may have the following side effects:

• Sore throat
• Headache
• Nosebleeds

Steroid tablets - in cases of larger polyps or more severe inflammation the patient may be prescribed steroid tablets; either on their own or to be taken along with a nasal spray. Although steroid tablets are very effective at shrinking polyps, there is a risk of more serious side effects, such as weight gain, and should be taken for a few weeks at the most.

Other medications - these will include drugs that help treat conditions which may be making the inflammation worse. Examples include antihistamines for allergies, antibiotics for infections, and antifungal drugs for fungal allergies.

Surgery - surgery is only used if the polyps are very large, or if the patient has not responded well to other treatments. Approximately 75% of patients find that their polyps grow back about 4 years after they have been surgically removed.

• Polypectomy - the surgeon enters through the nostrils. This procedure is the most common for the removal of polyps. The patient is given either a local or general anesthetic. Sometimes the surgeon may remove small pieces of bone from the nose to reduce the risk of recurrence.
  
  
• Endoscopic sinus surgery - this procedure is used if the polyps are particularly large, in clusters, or are seriously blocking the sinuses. A long thin tube with a video camera (endoscope) is inserted into the patient's nose and sinuses. Small cuts are made on the patient's face, through which surgical instruments are inserted to remove the polyps and open the sinus cavities.

After surgery the patient will most likely be prescribed a corticosteroid nasal spray to help prevent recurrence. Some doctors recommend the use of a saline (saltwater) rinse to help post-surgical healing.

What are the possible complications of nasal polyps?

A large polyp, or a cluster of them sometimes block the flow of air and draining of fluids from the sinuses and/or nasal cavity, leading to the following possible complications:

• Chronic or frequent sinus infections
• Obstructive sleep apnea
• The structure of the face may be altered, leading to double vision. Sometimes the eyes may be set wider apart than normal (more common in patients with cystic fibrosis).

Prevention of nasal polyps

Humidity - if the air in your home is dry use a humidifier.

Hygiene - regular and thorough handwashing reducing the risk of having a bacterial or viral infection, resulting in fewer cases of inflammation of the sinuses and nasal passages.

Irritants - avoiding irritants, such as some allergens, chemicals and airborne pollutants (which cause inflammation) may help some people reduce their risk of developing polyps.

Management of asthma and allergies - patients who follow their doctor's recommendations regarding asthma and/or allergy treatment are less likely to develop nasal polyps.

Nasal lavage or nasal rinse - rinsing the nasal passages with a nasal lavage or saline spray will help improve the flow of mucus, as well as removing irritants and allergens.

Written by Christian Nordqvist
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

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