Exercise-Induced Anaphylaxis

Aka: Exercise-Induced Anaphylaxis, Exercise-Induced Urticaria, Exercise Anaphylaxis

1. See also
   1. Exercise-Induced Asthma
   2. Anaphylaxis
   3. Urticaria
2. Definition
   1. Allergic symptoms in response to Exercise
3. Epidemiology
   1. On average, symptoms persist 10 years before diagnosis is made
4. Types
   1. CholinergicUrticaria
      1. Micropapular hives
         1. Erythematous halo with central 2 to 5 mm Papule
      2. Exaggerated response to Body Temperature
      3. Associated with rise in plasma histamine
   2. Variant Exercise-Induced Anaphylaxis
      1. Lesions similar to CholinergicUrticaria
      2. May progress to Anaphylaxis
   3. Food-Dependent Exercise-Induced Anaphylaxis (FDEIA)
   4. Classic Exercise-Induced Anaphylaxis
      1. Precipitated by Exercise at any level
      2. Criteria
         1. Angioedema or Urticaria and
         2. Airway obstruction and
         3. Hypotension
      3. Associated symptoms
         1. Generalized Pruritus
         2. Choking sensation
         3. Gastrointestinal colic
         4. Nausea
         5. Headache
         6. Wheezing
      4. Course
         1. Duration: 30 minutes to 4 hours after Exercise
5. Predisposing factors
   1. Family History
   2. Atopic history
   3. Specific food intakes prior to Exercise (in some cases any food before Exercise)
      1. Alcohol (common)
      2. Aspirin (common)
      3. NSAIDs (common)
      4. Seafood
      5. Celery
      6. Wheat
      7. Cheese
6. Diagnosis: CholinergicUrticaria
   1. Passive Warming Test
      1. Increase core Body Temperature >0.5 C or >0.9 F
         1. Patient immerses in warm water or
         2. Raise Ambient Temperature
      2. Interpretation
         1. CholinergicUrticaria: Plasma histamine increases
         2. Exercise-Induced Anaphylaxis: No histamine increase
   2. Methacholine Skin Test
      1. Methacholine 100 units in saline injected intradermal
      2. Positive test induces micropapular hives
      3. Test Sensitivity: 33%
      4. High Test Specificity
7. Diagnosis: Exercise-Induced Anaphylaxis
   1. Exercise challenge test with treadmill or Exercise bike
   2. Negative test does not rule out condition
   3. Emergency equipment must be available
      1. Epinephrine ready for Subcutaneous Injection
      2. Intubation equipment
      3. Oxygen Source
      4. Advanced Cardiac Life Support Cart
8. Management: General Measures
   1. Activity modification
      1. Exercise with partner with BLS training (and who carries an Epinephrine Auto-Injector)
      2. Avoid exacerbating factors before Exercise
         1. Do not Exercise for 4-6 hours after eating
         2. Avoid Aspirin or NSAIDs prior to Exercise
         3. Avoid exercising during Menses
   2. Self-Management of acute episodes
      1. Subcutaneous Epinephrine (Epi-Pen) always available
      2. Stop Exercise with onset of symptoms (early stopping may prevent full Anaphylaxis)
      3. Administer Epi-pen for first signs of Anaphylaxis
         1. Flushing
         2. Pruritus
      4. Pursue immediate medical care for progressing signs
9. Management: Medications
   1. Acute episode
      1. See Anaphylaxis
      2. See Urticaria
   2. Prevention
      1. Review if medication banned for competitive athlete
      2. Antihistamines
         1. Sedating Antihistamines: Hydroxyzine (Atarax)
         2. Non-Sedating Antihistamines: Allegra, Zyrtec
      3. Other potential agents
         1. Cromolyn Sodium (Intal)
         2. Leukotriene Antagonist (Singulair, Accolate, Zyflo)
10. References
    1. Mason and Pensa in Herbert (2018) EM:Rap 18(10): 4-5
    2. Hosey (2001) Am Fam Physician 64(8):1367-74 [PubMed]
    3. Volcheck (1997) Mayo Clin Proc 72:140-7 [PubMed]