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Chapter 221. Disorders of the Nose and Sinuses
Topics: Introduction | Fractures of the Nose | Deviated Septum | Perforations of the Septum | Nosebleeds | Nasal Vestibulitis | Rhinitis | Nasal Polyps | Sinusitis
 
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Rhinitis

Rhinitis is inflammation and swelling of the mucous membrane of the nose, characterized by a runny nose and stuffiness and usually caused by the common cold (see Section 17, Chapter 198) or an allergy (see Section 16, Chapter 185).

The nose is the most commonly infected part of the upper airways. Rhinitis may be acute (short-lived) or chronic (long-standing). Acute rhinitis commonly results from viral infections but may also be a result of allergies or other causes. Chronic rhinitis usually occurs with chronic sinusitis (chronic rhinosinusitis).

Viral Rhinitis: Acute viral rhinitis (the common cold) can be caused by a variety of viruses. Symptoms consist of runny nose, congestion, post-nasal drip, cough, and a low-grade fever. Stuffiness can be relieved by taking phenylephrine as a nasal spray or pseudoephedrine by mouth. These drugs, available over the counter, cause the blood vessels of the nasal mucous membrane to narrow (constrict). Nasal sprays should be used for only 3 or 4 days because after that period of time, when the effects of the drugs wear off, the mucous membrane often swells even more than before. This phenomenon is called rebound congestion. Antihistamines help control runny nose but cause drowsiness and other problems, especially in older people (see Section 2, Chapter 14). Antibiotics are not effective for acute viral rhinitis.

Allergic Rhinitis: Allergic rhinitis is caused by a reaction of the body's immune system to an environmental trigger. The most common environmental triggers include dust, molds, pollens, grasses, trees, and animals. Symptoms include sneezing, runny nose, stuffiness, and itchy, watery eyes. A doctor may diagnose allergic rhinitis based on a person's history of symptoms. Often, the person has a family history of allergies. More detailed information may be obtained using blood tests or skin testing.

Avoiding the substance that triggers the allergy prevents symptoms but is often not possible. Nasal corticosteroid sprays decrease nasal inflammation caused by many sources and are relatively safe for long-term use. Antihistamines help prevent the allergic reaction and thus symptoms. Antihistamines dry the mucous membrane of the nose but many of them also cause sleepiness and other problems, especially in older people. Newer ones require a prescription but do not have these side effects. Allergy shots (desensitization) help to build long-term tolerance to specific environmental triggers, but they may take months or years to become fully effective. Antibiotics do not relieve the symptoms of allergic rhinitis.

Atrophic Rhinitis: Atrophic rhinitis is a form of chronic rhinitis in which the mucous membrane thins (atrophies) and hardens, causing the nasal passages to widen (dilate) and dry out. The cells normally found in the mucous membrane of the nose--cells that secrete mucus and have hairlike projections to move dirt particles out--are replaced by cells like those normally found in the skin. The disorder can develop in someone who had sinus surgery in which a significant amount of intranasal structures and mucous membranes were removed. A prolonged bacterial infection of the lining of the nose is also a factor.

Crusts form inside the nose, and an offensive odor develops. A person may have recurring severe nosebleeds and can lose his sense of smell (anosmia).

Treatment is aimed at reducing the crusting, eliminating the odor, and reducing infections. Topical antibiotics, such as bacitracin applied inside the nose, kill bacteria. Estrogens and vitamins A and D sprayed into the nose or taken by mouth may reduce crusting by promoting mucosal secretions. Other antibiotics, given by mouth or intravenously, may also be helpful. Surgery to narrow the nasal passages may reduce crusting because the decreased airflow prevents drying of the thinned mucous membrane.

Vasomotor Rhinitis: Vasomotor rhinitis is a form of chronic rhinitis. Nasal stuffiness, sneezing, and a runny nose--common allergic symptoms--occur when allergies do not appear to be present. In some people, the nose reacts strongly to irritants (such as dust and pollen), perfumes, and pollution. The disorder comes and goes but is worsened by dry air. The swollen mucous membrane varies from bright red to purple. Sometimes, people also have slight inflammation of the sinuses. When persistent, endoscopy of the nose or computed tomography (CT) of the sinuses may be needed. If inflammation of the sinus is not significant, treatment is aimed at relieving symptoms. Avoiding smoke and irritants and using a humidified central heating system or vaporizer to increase humidity may be beneficial.

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