Exercise induced anaphylaxis

Exercise Induced Anaphylaxis

Exercise Induced Anaphylaxis (EIA) is a rare but potentially life-threatening condition characterized by an allergic reaction triggered by physical activity. This condition can occur in individuals with or without a history of allergies and is often unpredictable in its onset and severity.

Pathophysiology

The exact mechanism of exercise induced anaphylaxis is not fully understood. However, it is believed to involve a complex interaction between physical exertion and the immune system. During exercise, physiological changes such as increased blood flow, elevated body temperature, and changes in pH levels may contribute to the release of histamine and other mediators from mast cells. These mediators can cause the symptoms associated with anaphylaxis, such as urticaria, angioedema, and bronchospasm.

Triggers

While exercise alone can trigger anaphylaxis, certain factors may increase the risk:

• Food-dependent exercise induced anaphylaxis (FDEIA): Some individuals experience anaphylaxis only when they exercise after consuming specific foods, such as wheat, shellfish, or nuts.
• Environmental factors: High humidity, extreme temperatures, and exposure to pollutants may exacerbate symptoms.
• Medications: Certain medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), can increase susceptibility to EIA.

Symptoms

Symptoms of exercise induced anaphylaxis can vary widely but often include:

• Urticaria (hives)
• Angioedema (swelling)
• Wheezing or difficulty breathing
• Gastrointestinal distress, such as nausea or vomiting
• Hypotension (low blood pressure)
• Syncope (fainting)

Diagnosis

Diagnosing exercise induced anaphylaxis can be challenging due to its episodic nature. A thorough medical history and physical examination are essential. Physicians may also conduct:

• Exercise challenge tests: To reproduce symptoms under controlled conditions.
• Allergy testing: To identify potential food or environmental triggers.
• Blood tests: To measure levels of tryptase and other markers of mast cell activation.

Management

Management of exercise induced anaphylaxis involves both prevention and treatment:

• Avoidance of known triggers: Patients should avoid exercising after consuming foods known to trigger symptoms.
• Medication: Carrying an epinephrine auto-injector is crucial for immediate treatment of anaphylactic reactions.
• Education: Patients should be educated about recognizing early symptoms and the importance of prompt treatment.

Prognosis

With proper management, individuals with exercise induced anaphylaxis can often continue to engage in physical activity. However, they must remain vigilant about avoiding known triggers and carrying emergency medication.

Also see

• Anaphylaxis
• Food allergy
• Mast cell activation syndrome
• Histamine