Nasal polyps are growths in the nasal cavities or in the sinuses. They are mostly non-cancerous but can block the nasal passage causing many problems. This article explains the causes of nasal polyps and explains how it is diagnosed.

Nasal Mucosal Inflammation
One of the main causes of nasal polyps is inflammation of the nasal mucosa. The mucosa is a layer in the nasal and sinus cavities that provides protection. It is wet in nature and helps to humidify air. Sometimes the nasal mucosa may become inflamed. This can happen due to allergies, infections, or other reasons.

The inflammation of the nasal mucosa causes it to be irritated. If this persists, then the mucosa may develop a round structure known as a polyp. The nasal polyp can be so small that it may be undetected and may not even cause symptoms. If it grows in size, then it can block the nose causing various symptoms.

Some experts believe that irritation of the nasal mucosa causes fluid to accumulate in the space between mucosal cells. These cells become heavy and they come down to form polyps.

Common Triggers
The inflammation of the nasal mucosa causes polyps to grow. The reason for this inflammation can vary from person to person. In most cases, there would be some cause that triggers the inflammation. These causes can trigger the growth of nasal polyps.

Some of the common triggers include:

• Infection in the sinus (sinusitis), particularly infections that occur repeatedly.
• Cystic fibrosis is known to cause mucus buildup. It can be reason for the growth of nasal polyps.
• Allergic rhinitis can cause inflammation of the nasal mucosa. It is commonly known as hay fever.
• Sometimes medications like aspirin and ibuprofen can act as a trigger leading to inflammation of the nasal mucosa.
• In some people, low levels of Vitamin D is believed to be responsible for nasal polyp growth.
• Asthma is a condition that can trigger nasal polyp growth.

In some people, there may be no apparent cause but yet they develop nasal polyps.

Diagnosis
It is very difficult to detect nasal polyps just by looking in the mirror. Someone who experiences symptoms like nose block, congestion, breathing problems, etc. may visit a doctor who would make an examination to check for nasal polyps.

The nasoscope or otoscope is a device that helps the doctor look into the nasal passage to spot polyps. If the polyps are deep inside, the doctor may use nasal endoscopy, where a thin tube that has light and a camera is inserted into the nose. This provides visual confirmation of nasal polyps.

Sometimes CT scan/MRI scan may be required to diagnose polyps. These scans detect nasal polyps by showing them as opaque spots.

Allergy tests may be done to determine if the condition is due to allergy to some substance.