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A. Evaluation by system: 2. HEENT |
Allergic RhinitisBetty Wray, MD and Allergy-Immunology Section Allergic Rhinitis – Diagnosis Introduction: Allergic rhinitis is extremely common affecting 14-20% of the general population, and 60-70% of atopic patients. It is seen more commonly if there is a family history of allergy, and begins from infancy to young adulthood. Allergies can be classified as seasonal (e.g. tree pollens in spring, grass in late spring and summer, ragweed in late summer and fall), perennial (house dust mites, molds, animal dander, foods) or irritants (smoke, gas fumes). Pathogenesis: Allergens bind to specific IgE on surface of mast cells in respiratory tissue. Bridging of IgE triggers release of chemical mediators such as histamine, leukotrienes, C4, D4. Evaluation: The history is the most important part of the evaluation. Symptoms such as rhinorrhea, nasal congestion, paroxysms of sneezing, postnasal drip, pruritus of eyes, nose, soft palate and ears, allergic salute, snorting and sniffing, seasonal and dietary variations/exposures. The physical examination should be focused on the identification of injected conjunctivae, transverse nasal creases, pale, edematous nasal mucosa, allergic shiners, Dennie-Morgan lines, lymphoid hyperplasia and cobblestoning of the posterior pharyngeal wall. Laboratory evaluation could include a nasal smear for eosinophiles (Hansel stain), and prick skin tests. The number of tests will vary with the age of the child, but in infants the most commonly tested allergens include milk, eggs and soy. Much more extensive testing can be done in older patients depending on the symptoms, history, and physical findings. Intradermal tests are rarely performed. The following tests are rarely helpful: CBC with differential, serum IgE, RAST testing. The latter used primarily when an extensive rash - such as atopic dermatitis - is present or there is a history of severe reactions. Differential Diagnosis: Patients may have combinations and are called “overlap” syndromes:
Other possible causes of symptoms seen in allergic rhinitis could include: NARES (non-allergic rhinitis with eosinophils); septal deviation; nasal polyps; rhinitis of pregnancy, foreign bodies, tumors, hypothyroidism and nasal mastocytosis. Complications: There has been some controversy in the literature about whether treating allergic rhinitis aggressively will prevent the onset of asthma. The following can often be seen:
Allergic Rhinitis – Treatment Introduction: Treatment should include avoidance measures as well as medications. Referral to an allergist should occur when symptoms persist despite medications and simple home precautions or if the patient had complications or when the cause of the symptoms is unclear. Preventive Measures: For dust mite avoidance, hand-outs to give parents can be helpful instructing parents how to “desensitize” a bedroom. Zip-up impermeable covers for mattress and pillows will prevent mold sensitivity and manage house dust mites. Air cleaners are most useful with smokers in the home. Saline nose drops can provide symptomatic relief. Medications: Includes antihistamines, topical steroids, and miscellaneous medications:
Topical Steroids: Remember: Dose is Additive to other steroids being taken
Immunotherapy: Efficacy of this treatment has been proven for ragweed, grass, tree pollens and dust mites. It is most effective in seasonal pollinosis, and also can control perennial symptoms. It works by increasing IgG blocking antibodies; also blunts rise of IgE. |
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© Medical College of Georgia |
Department of Pediatrics |
Medical College of Georgia February 27, 2004 |