Rhinitis is inflammation of the nasal mucous membrane, with resultant nasal congestion, rhinorrhea, and variable associated symptoms depending on etiology (eg, itching, sneezing, watery or purulent rhinorrhea, anosmia). Rhinitis is classified as allergic or nonallergic. The cause of nonallergic rhinitis is usually viral, although irritants can cause it. Diagnosis is usually clinical. Treatment includes humidification of room air, sympathomimetic amines, and antihistamines. Bacterial superinfection requires appropriate antibiotic treatment.
There are several forms of nonallergic rhinitis. For allergic rhinitis, see Allergic Rhinitis.
Acute rhinitis, manifesting with edema and vasodilation of the nasal mucous membrane, rhinorrhea, and obstruction, is usually the result of a common cold; other causes include streptococcal, pneumococcal, and staphylococcal infections.
Chronic rhinitis is generally a prolongation of subacute (resolved in 30 to 90 days) inflammatory or infectious viral rhinitis. It may also rarely occur in syphilis, TB, rhinoscleroma, rhinosporidiosis, leishmaniasis, blastomycosis, histoplasmosis, and leprosy—all of which are characterized by granuloma formation and destruction of soft tissue, cartilage, and bone. Nasal obstruction, purulent rhinorrhea, and frequent bleeding result. Rhinoscleroma causes progressive nasal obstruction from indurated inflammatory tissue in the lamina propria. Rhinosporidiosis is characterized by bleeding polyps. Both low humidity and airborne irritants can result in chronic rhinitis.
Atrophic rhinitis, a form of chronic rhinitis, results in atrophy and sclerosis of mucous membrane; the mucous membrane changes from ciliated pseudostratified columnar epithelium to stratified squamous epithelium, and the lamina propria is reduced in amount and vascularity. Atrophic rhinitis is associated with advanced age, granulomatosis with polyangiitis (GPA, formerly known as Wegener granulomatosis), and iatrogenically induced excessive nasal tissue extirpation. Although the exact etiology is unknown, bacterial infection frequently plays a role. Nasal mucosal atrophy often occurs in the elderly.
Acute rhinitis results in cough, low-grade fever, nasal congestion, rhinorrhea, and sneezing.
Chronic rhinitis manifestations are similar to those of acute rhinitis, but in prolonged or severe cases, patients may also have thick, foul-smelling, mucopurulent drainage; mucosal crusting; and/or bleeding.
Atrophic rhinitis results in enlargement of the nasal cavities, crust formation and malodorous bacterial colonization, nasal congestion, anosmia, and epistaxis that may be recurrent and severe.
Vasomotor rhinitis results in sneezing and watery rhinorrhea. The turgescent mucous membrane varies from bright red to purple. The condition is marked by periods of remission and exacerbation.
The different forms of rhinitis are diagnosed clinically. Testing is unnecessary.
Vasomotor rhinitis is differentiated from specific viral and bacterial infections of the nose by the lack of purulent exudate and crusting. It is differentiated from allergic rhinitis by the absence of an identifiable allergen.
Viral rhinitis may be treated symptomatically with decongestants (either topical vasoconstriction with a sympathomimetic amine, such as oxymetazoline q 8 to 12 h or phenylephrine 0.25% q 3 to 4 h for not more than 7 days, or systemic sympathomimetic amines, such as pseudoephedrine 30 mg po q 4 to 6 h). Antihistamines (see Table: Inhaled Nasal Mast Cell Stabilizers) may be helpful, but those with anticholinergic properties dry mucous membranes and therefore may increase irritation. (See also Common Cold.) Decongestants also may relieve symptoms of acute bacterial rhinitis and chronic rhinitis, whereas an underlying bacterial infection requires culture, pathogen identification, antibiotic sensitivities, and appropriate antimicrobial treatment. If symptoms persist, particularly in dry, crusted, atrophic rhinitis, biopsy may be necessary to rule out cancer.
Treatment of atrophic rhinitis is directed at reducing the crusting and eliminating the odor with nasal irrigation, topical antibiotics (eg, bacitracin, mupirocin), topical or systemic estrogens, and vitamins A and D. Occluding or reducing the patency of the nasal cavities surgically decreases the crusting caused by the drying effect of air flowing over the atrophic mucous membrane.
Treatment of vasomotor rhinitis is by trial and error and is not always satisfactory. Patients benefit from humidified air, which may be provided by a humidified central heating system or a vaporizer in the workroom or bedroom. Topical corticosteroids (eg, mometasone 2 sprays bid) and nasal antihistamines can be of some benefit. Systemic sympathomimetic amines (eg, for adults, pseudoephedrine 30 mg po q 4 to 6 h prn) relieve symptoms but are not recommended for long-term use because they thicken the mucus and may cause tachycardia and nervousness. Topical vasoconstrictors are avoided because they cause the vasculature of the nasal mucous membrane to lose its sensitivity to other vasoconstrictive stimuli—eg, the humidity and temperature of inspired air.