Allergy and Immunology in ENT: Rhinitis, Testing, and Immunotherapy
Scope
Allergy and immunology in ENT tests allergic rhinitis diagnosis, skin prick and specific IgE testing, pharmacotherapy, immunotherapy, drug allergy, and warning signs of immunodeficiency.
Core rules
- Allergic rhinitis is IgE-mediated and causes sneezing, clear rhinorrhea, itching, and nasal obstruction. Diagnosis requires compatible history plus sensitization on skin prick or specific IgE testing; testing without history produces false positives.
- First-line treatment is intranasal corticosteroid plus saline. Second-generation antihistamines are adjuncts. Avoid long-term topical decongestants because of rhinitis medicamentosa.
- Allergen immunotherapy is considered for moderate-to-severe disease despite pharmacotherapy. Subcutaneous or sublingual courses last 3 to 5 years; anaphylaxis risk requires observation and epinephrine availability.
- Local allergic rhinitis has nasal symptoms and local IgE but negative systemic tests; nasal provocation can confirm.
- Drug allergy: obtain a structured history; penicillin skin testing is used when indicated.
- Recurrent sinopulmonary infections suggest immunodeficiency; check immunoglobulins and vaccine responses.
Worked example
A 25-year-old has seasonal sneezing, clear rhinorrhea, and itchy eyes, with a positive dust mite skin prick and failed antihistamine therapy. The diagnosis is allergic rhinitis with sensitization to dust mite. Start intranasal corticosteroid and saline; if symptoms remain moderate to severe, offer immunotherapy for 3 to 5 years after discussing anaphylaxis risk.
Traps
Ordering broad IgE panels without history; using intradermal testing first; stopping antihistamines improperly before testing; treating rhinitis medicamentosa with more decongestant; and missing coexisting asthma.