para>Chronic nasal obstruction can result in facial deformities, dental malocclusions, and sleep disorders.
Pregnancy Considerations
Physiologic changes during pregnancy may aggravate all types of rhinitis, frequently in the 2nd trimester.
EPIDEMIOLOGY
- Onset usually in first 2 decades, rarely before 6 months of age, with tendency declining with advancing age.
- The mean age of onset is 8 to 11 years, and about 80% of cases have established allergic rhinitis by age 20 years.
Prevalence
- ’ Ό10 " 25% of the U.S. adult population and 9 " 42% of the U.S. pediatric population are affected.
- 44 " 87% of patients with allergic rhinitis have mixed allergic and nonallergic rhinitis, which is more common than either pure form (1).
- Scandinavian studies have demonstrated cumulative prevalence rate of 14% in men and 15% in women.
ETIOLOGY AND PATHOPHYSIOLOGY
- Aeroallergen-driven mucosal inflammation due to resident and infiltrating inflammatory cells, as well as vasoactive and proinflammatory mediators (e.g., cytokines)
- Inhalant allergens:
- Perennial: house dust mites, indoor molds, animal dander, cockroach/insect detritus
- Seasonal: tree, grass, and weed pollens; outdoor molds
- Occupational: latex, plant products (e.g., baking flour), sensitizing chemicals, and certain animals for people working in farms and vet clinics
Genetics
Complex but strong genetic predilection present (80% have family history of allergic disorders)
RISK FACTORS
- Family history of atopy, with a greater risk if both parents have atopy
- Higher socioeconomic status
- Tobacco smoke can exacerbate symptoms and increase risk of developing asthma in patients with allergic rhinitis.
- Having other allergies like asthma
- Unclear evidence regarding risk due to early, repeated exposure to offending allergen and early introduction of solid food.
- Pets in house and houses infested with cockroaches can cause perennial allergic rhinitis.
GENERAL PREVENTION
- Primary prevention of atopic disease has not been proven effective by maternal diet or maternal allergen avoidance (2).
- Exclusive breastfeeding to 6 months of age lowers risk of some atopic disorders
- Symptomatic control by environmental avoidance is the "first-line treatment. "
- No evidence to support use of acaricides with mite-proof mattress and pillow covers, carpet and drape removal, removal of plants in the home, and pet control (2,3)[B].
- Air conditioning and limited outside exposure during allergy season (1)[B]
- HEPA air cleaners and vacuum bags of unclear efficacy
- Close doors and windows during allergy season.
- Use a dehumidifier to reduce indoor humidity.
COMMONLY ASSOCIATED CONDITIONS
Other IgE-mediated conditions: asthma, atopic dermatitis, allergic conjunctivitis, food allergy
DIAGNOSIS
Diagnosis is made primarily by history and physical exam.
HISTORY
- Evaluation of nature, duration, and time course of symptoms
- History of atopic dermatitis and/or food allergies
- History of nasal congestion; rhinorrhea; pruritus of nose, eyes, ears, and/or palate; sneezing; itching; and watering eyes
- Family history of allergic diseases
- History of environmental and occupational exposure and various nasal stimuli can help differentiate between allergic and vasomotor rhinitis.
PHYSICAL EXAM
Many findings are suggestive of but not specific for allergic rhinitis:
- Dark circles under eyes, "allergic shiners " (infraorbital venous congestion)
- Transverse nasal crease from rubbing nose upward; typically seen in children
- Rhinorrhea, usually with clear discharge
- Pale, boggy, blue-gray nasal mucosa
- Postnasal mucus discharge
- Oropharyngeal lymphoid tissue hypertrophy
DIFFERENTIAL DIAGNOSIS
- Infectious rhinitis: usually viral, commonly with secondary bacterial infection
- Usually associated with sinusitis and is known as rhinosinusitis
- Viral rhinitis averages 6 episodes/year from ages 2 to 6 years.
- IgA deficiency with recurrent sinusitis
- Rhinitis medicamentosa:
- Rebound effect associated with continued use of topical decongestant drops and sprays
- ACE inhibitors, reserpine, ²-blockers, oral contraceptive pills (OCPs), guanethidine, methyldopa
- Aspirin, NSAIDs
- Vasomotor (idiopathic) rhinitis caused by numerous nasal stimuli like warm or cold air, scents and odors, light or particulate matter
- Hormonal: pregnancy, thyroid, OCPs
- Nonallergic rhinitis with eosinophilia syndrome (NARES)
- Gustatory: watery rhinorrhea in response to alcohol or food
- "Skier 's nose " : watery rhinorrhea in response to cold air
- Conditions associated with rhinitis:
- Nasal polyps, tumor
- Septal/anatomic obstruction
- Adenoidal hypertrophy, particularly in children
- Septal abnormality or deflected nasal septum (DNS) in adults
DIAGNOSTIC TESTS & INTERPRETATION
- Lab tests rarely needed
- Skin testing is done to identify the allergen for immunotherapy.
Initial Tests (lab, imaging)
- Testing is rarely indicated.
- If diagnosis implies other causes, consider the following:
- CBC with differential may show elevated eosinophils.
- Increased total serum IgE level
- Nasal probe smear may show elevated eosinophils.
- Medications that may alter lab results
- Corticosteroids may decrease eosinophilia.
- Antihistamines suppress reactivity to skin tests; stop antihistamines 7 days before testing.
- CT scan of sinuses is not routinely done but can be used to check for complete opacity, fluid level, and mucosal thickening.
Diagnostic Procedures/Other
- Consider testing in only those cases where allergic symptoms do not respond to treatment and/or considering immunotherapy.
- Specific allergen sensitivity with allergen skin testing or radioallergosorbent testing (RAST); clinical correlation based on history is essential in interpreting results.
- Diagnostic allergen prick tests are used to select agent to determine appropriate environmental control measures, as well as to direct immunotherapy:
- Prick or puncture: superficial injury to epidermis with application of test antigen
- Intradermal
- RAST: more expensive and less sensitive than skin testing; typically used in patients in whom skin testing is not practical or a severe reaction is possible
- Rhinoscopy: useful to visualize intranasal anatomy and posterior pharyngeal structures, including adenoids, polyps, and larynx
Test Interpretation
- Nasal washing/scraping: Eosinophils predominate but may see basophils, mast cells.
- Nasal mucosa: submucosal edema but without destruction; eosinophilic infiltration; congested mucous glands and goblet cells
TREATMENT
There are three mainstays of treatment of allergic rhinitis:
- Allergen avoidance
- Medication
- Allergy immunotherapy
GENERAL MEASURES
- Establish specific cause(s) by history and appropriate testing.
- Limit exposure to offending allergen.
- Allergen immunotherapy (desensitization)
- Reserved when symptoms are uncontrollable with medical therapy or have a comorbidity (e.g., asthma)
- Specific allergen extract is injected SC in increasing doses to induce patient tolerance.
MEDICATION
Oral medication and intranasal sprays are commonly used.
First Line
- Mild symptoms: 2nd-generation nonsedating antihistamines are the first-line therapy for mild to moderate allergic rhinitis (1,4).
- Adverse effects: mild sedation, mild anticholinergic effects
- Generic (cetirizine, fexofenadine, loratadine; most to least effective)
- Levocetirizine is a new 2nd-generation nonsedating antihistamine that is effective but costly.
- Intranasal corticosteroids are 1st-line therapy for moderate to severe allergic rhinitis (1,4)[A]:
- Most effective drug class for symptoms of allergic rhinitis
- Use nasal sprays after showering and direct spray away from septum to improve deposition on mucosal surface.
- May be used as needed; however, less effective than regular use (1)
- Adverse effects: nosebleed, nasal septal perforation, and systemic corticosteroid effects
- Systemic steroids should be considered only in urgent cases and only for short-term use.
Second Line
1st-generation antihistamines, such as the following:
- Brompheniramine: 12 to 24 mg PO BID
- Chlorpheniramine: 4 mg PO q4 " 6h PRN
- Clemastine: 1 to 2 mg PO BID PRN
- Diphenhydramine: 25 to 50 mg PO q4 " 6h PRN:
- May precipitate urinary retention in men with prostatism and/or hypertrophy
- Adverse effects: sedation, prolonged QT interval, performance impairment, and anticholinergic effect
- Nasal antihistamines effective but may be systemically absorbed and thus cause sedation: azelastine, olopatadine
- Decongestants
- Phenylephrine: 10 mg PO q4h PRN
- Pseudoephedrine: 60 mg PO q4 " 6h PRN
- Oxymetazoline nasal spray (Afrin): 2 to 3 sprays per nostril q10 " 12h PRN (max 3 days). Intranasal agents should not be used for >3 days due to rebound rhinitis. Discourage use in patients with hypertension (HTN) or cardiac arrhythmia.
- Intranasal anticholinergics such as ipratropium nasal spray 2 sprays per nostril BID to TID
- Intranasal anticholinergics can increase efficacy in combination with steroid use.
- Leukotriene antagonists such as montelukast 10 mg/day PO
- Should generally be used as an adjunct, not monotherapy
- May be first line in those with concomitant asthma
- Mast cell stabilizers such as cromolyn nasal spray 1 spray per nostril TID to QID
- May take 2 to 4 weeks of therapy for optimal efficacy
- May be ineffective in patients with nonallergic rhinitis and nasal polyps
ISSUES FOR REFERRAL
Refer to allergist for consideration of immunotherapy.
ADDITIONAL THERAPIES
- Immunotherapy, either by injection (5)[A] or sublingually, which may be better tolerated by children (6)[A]
- Nasal saline use has evidence of efficacy as sole agent or as adjunctive treatment (1,7)[A].
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
No specific restrictions on activity; emphasize avoiding activity where exposure to the allergen is likely.
Patient Monitoring
Initiation of patient education is critical.
DIET
- No special diet unless concomitant food reactions are suspected and evaluated
- Some patients with severe sensitivity to seasonal pollens may have oral allergy syndrome, which is associated with itching in the mouth with the ingestion of fresh fruits that may cross-react with the allergens.
PATIENT EDUCATION
- Asthma & Allergy Foundation of America, 1717 Massachusetts Ave., Suite 305, Washington, DC 20036; (800) 7-ASTHMA: http://www.aafa.org/
- Other helpful information available at http://www.acaai.org/ and http://www.aaaai.org/home.aspx
PROGNOSIS
- Acceptable control of symptoms is the goal.
- Treatment is helpful to reduce the risk of comorbidities, such as sinusitis and asthma.
COMPLICATIONS
- Secondary infection such as otitis media or sinusitis
- Epistaxis
- Nasopharyngeal lymphoid hyperplasia
- Airway hyperreactivity with allergen exposure
- Asthma
- Facial changes, especially in children who are mouth breathers
- Sleep disturbance
REFERENCES
11 Wallace DV, Dykewicz MS, Bernstein DI, et al. The diagnosis and management of rhinitis: an updated practice parameter. J Allergy Clin Immunol. 2008;122(2 Suppl):S1 " S84.22 Kramer MS, Kakuma R. Maternal dietary antigen avoidance during pregnancy or lactation, or both, for preventing or treating atopic disease in the child. Cochrane Database Syst Rev. 2012;(9):CD000133.33 Sheikh A, Hurwitz B, Nurmatov U, et al. House dust mite avoidance measures for perennial allergic rhinitis. Cochrane Database Syst Rev. 2010;(7):CD001563.44 Plaut M, Valentine MD. Clinical practice. Allergic rhinitis. N Engl J Med. 2005;353(18):1934 " 1944.55 Calderon MA, Alves B, Jacobson M, et al. Allergen injection immunotherapy for seasonal allergic rhinitis. Cochrane Database Syst Rev. 2007;(1):CD001936.66 Wilson DR, Lima MT, Durham SR. Sublingual immunotherapy for allergic rhinitis: systematic review and meta-analysis. Allergy. 2005;60(1):4 " 12.77 Harvey R, Hannan SA, Badia L, et al. Nasal saline irrigations for the symptoms of chronic rhinosinusitis. Cochrane Database Syst Rev. 2007;(3):CD006394.
SEE ALSO
Conjunctivitis, Acute
CODES
ICD10
- J30.9 Allergic rhinitis, unspecified
- J30.1 Allergic rhinitis due to pollen
- J30.2 Other seasonal allergic rhinitis
- J30.81 Allergic rhinitis due to animal (cat) (dog) hair and dander
- J30.5 Allergic rhinitis due to food
- J30.89 Other allergic rhinitis
ICD9
- 477.9 Allergic rhinitis, cause unspecified
- 477.0 Allergic rhinitis due to pollen
- 477.8 Allergic rhinitis due to other allergen
- 477.2 Allergic rhinitis due to animal (cat) (dog) hair and dander
- 477.1 Allergic rhinitis due to food
SNOMED
- 61582004 Allergic rhinitis (disorder)
- 21719001 allergic rhinitis due to pollen (disorder)
- 367498001 Seasonal allergic rhinitis (disorder)
- 91925003 Allergic rhinitis due to animals
- 441978001 Allergic rhinitis due to food
- 446096008 perennial allergic rhinitis (disorder)
CLINICAL PEARLS
- Nasal saline irrigation (flushing 6 to 8 oz) may be very helpful in clearing upper airway of secretions and may precede the use of nasal corticosteroids.
- 2nd-generation antihistamines and intranasal corticosteroids are first-line therapies for allergic rhinitis.
- Referral to allergist is appropriate for identification of offending allergens and consideration of immunotherapy for inadequate symptom control.