Snap Shot A 15-year-old boy presents to with clear fluid discharge from his nose for 2 days duration. This has also been associated with sneezing. On nasal exam, the mucosa and turbinates appear edematous and slightly bluish (allergic rhinitis). Overview Inflammation of nasal mucosa with one or more of the following for at least one hour on a majority of days: sneezing itching rhinorrhea nasal congestion Classification Allergic IgE-mediated seasonal perennial reaction to perennial aeroallergens including dust mites, mold, animal dander, pollen episodic after a specific aeroallergen exposure Nonallergic not IgE-mediated eosinophilic rhinitis (NARES – nonallergic rhinitis with eosinophilia syndrome) symptoms are similar to perennial but no identifiable allergen hypersensitivity respond to intranasal corticosteroids vasomotor rhinitis thought to be caused by imbalance of autonomic nervous supply blood vessels become engorged causing obstruction can occur with strong smells, irritants, cold air Infectious acute 98% caused by viruses symptoms include nasal congestion, mucopurulent nasal discharge, pain and pressure, headache, olfactory disturbance, post nasal drainage, cough Others occupational hormonal such as in pregnancy, which can start after second month of pregnancy and resolves within two weeks after delivery menstrual cycle drug-induced e.g., ACEi, phentolamine, ASA, NSAIDs rhinitis medicamentosa rebound nasal congestion after overuse of alpha-adrenergic decongestants or cocaine irritants emotional such as with sexual arousal (honeymoon rhinitis) food atrophic characterized by significant crusting and foul odor geriatric idiopathic Epidemiology 30 - 60 million in the United States 10 - 30% of adults Up to 40% children Risk factors family history of atopy serum IgE >100 IU/ml before age of 6 high socioeconomic class positive allergy skin prick test Pathogenesis Mucosal inflammation caused by infiltrating inflammatory cells, vasoactive and pro-inflammatory mediators, sensory nerve activation, plasma leakage and congestion. Diagnosis and Evaluation Clinical diagnosis based upon history and physical Conditions that mimic rhinitis that need to be on differential nasal polyps anatomic anomalies CSF leaks ciliary dysfunction Skin testing IgE immunoassays Nasal endoscopy Nasal smears Management Limit exposure to antigens Oral antihistamines for allergic rhinitis Intranasal antihistamines efficacious and equal to oral antihistamines for treatment of seasonal allergic rhinitis Oral and topical decongestants e.g., pseudoephedrine should be limited to short-term use because of the risk rhinitis medicamentosa Intranasal corticosteroids Oral corticosteroids for short course treatment of very severe or intractable nasal symptoms Intranasal anticholinergic effective for rhinorrhea of nonallergic rhinitis Nasal saline Allergan immunotherapy Acute infectious rhinitis often caused by virus 7 - 10 days of observation risk of development for bacterial sinusitis in which case antibiotics can be beneficial see Common cold topic