Nasal polyps are benign, soft, painless tumors formed from edematous, chronically inflamed nasal mucosa. They usually arise from the ethmoidal sinus and occur in the middle meatus of the nose.

There are no subtypes for the nasal polyps.

The exact cause of polyposis is still unknown. Cystic fibrosis is the most common childhood cause of nasal polyposis. Polyps are also seen in patients with chronic sinusitis and allergic fungal sinusitis. Human papillomavirus may cause an inverted papilloma, which presents as a polyp causing unilateral nasal obstruction.

There is a specific rare metabolic disorder of arachidonic acid metabolism triggered by exogenous aspirin intake—known as aspirin-exacerbated respiratory disease. Also known by Samter's triad, patients with this syndrome have asthma and a skin rash by aspirin ingestion, and often have chronic nasal polyposis.

• Male sex
• Increasing age
• Asthma
• Family history of nasal polyposis

It is traditionally accepted that the presence of nasal polyps is the end product of long-lasting inflammation. The exact mechanism for the developments is poorly understood and most likely to be multifactorial. The contributing factors are inflammatory mediators, bacteria, genetics, etc.

Nasal polyps typically begin near the ethmoid sinuses in the middle meatus and extend into the nose, where they block the nasal airway and/or sinuses. Large or multiple polyps can completely obstruct the nasal passage.

Asymptomatic nasal polyps may be present transiently or persist and thus remain undiagnosed until they are discovered by routine examination.

Symptoms are likely to be described bilateral in most of the patients and complaints usually include the following:

• Nasal obstruction and congestion
• Runny nose
• Altered smell ranging from hyposmia (reduced ability to smell and detect odors) to anosmia (inability to perceive an odor)
• Hyponasal speech
• Mouth breathing
• Facial pain, pressure or fullness and headache due to impaired ventilation and drainage in the paranasal sinuses
• Snoring
• Frequent throat clearing due to associated postnasal drainage

Rarely, facial asymmetry or orbital involvement will be the presenting sign of long-ignored nasal polyps.

Nasal endoscopic examination remains the gold standard for diagnosis of nasal polyps. Computer tomography (CT) is the suggested imaging for diagnosis, superior to other imaging modalities to determine the sinonasal bony anatomy, extent, and localization of the disease process, and identify complications if they have occurred.

Mild to moderate polyps can be managed medically. Benign inflammatory nasal polyps frequently respond to topical and oral steroids. Medical management include:

• Nasal corticosteroid sprays for acutely and long-lasting treatment
• Antihistamines if allergic symptoms are preserved as well
• Short courses of oral corticosteroids in severe cases

Extensive nasal polyps are rarely treated with medical therapy alone, requiring surgical removal to reduce the mucosal inflammatory load. Once nasal polyps have been removed surgically, the medical management of the underlying mucosal inflammatory disease is then of the utmost importance.

Complication development is associated with the block of the airflow and fluid drainage. Potential complications are:

• Obstructive sleep apnea: complete or partial obstruction of the upper airway.
• Asthma exacerbation

Sinus infection: they can become more severe and frequent

You may help to reduce the chances of developing nasal polyps following these strategies:

• Manage allergies and asthma
• Avoid nasal irritants such as allergens, tobacco smoke, chemical fumes, dust, fine debris
• Practice good hygiene by washing your hands regularly to protect yourself against bacterial and viral infections
• Use a humidifier if the airs in your home tend to be dry

The physician may recommend long-term medical prophylaxis with topical steroid sprays

The pathophysiology of nasal polyposis is poorly understood, and the prognosis is guarded even with modern surgical techniques, there is no way to prevent a recurrence.

According to a study published in European Journal of Allergy and Immunology in 2005, the average onset is ~42 years, they are uncommon under the age of 20 and more frequently found in men than in women. They occur in all races and become more common with age.

A population-based study in Sweden, in 2003 reported a prevalence of nasal polyps of 2.7% of the total population. Using a disease-specific questionnaire, a study published in the European Journal of Allergy and Immunology in 2005 reported a prevalence of nasal polyps of 2.1% in France.