Diagnosis and Assessment Exercise-Induced Anaphylaxis (EIA)
ÎExercise is the immediate trigger for the development of symptoms in EIA. Typical symptoms include warmth, flushing, pruritus, and urticaria, occasionally progressing to angioedema, wheezing, upper airway obstruction, and collapse. (A)
ÎThe pathophysiologic events during exercise that precipitate symptoms are not known, although promising lines of research exist. (C)
ÎSome patients experience symptoms only if other contributing factors or ''co-triggers'' are present in association with exercise. These co-triggers include ingestion of specific foods, or in some patients ingestion of any food, nonsteroidal anti-inflammatory drugs, and high pollen levels. (C)
ÎThe clinical history should focus on identification of these possible co-triggers. Evaluation for sensitization to food allergens, particularly grains and seafood, should be performed. The diagnosis is usually made based upon history and exclusion of other disorders. Exercise challenge testing does not consistently reproduce symptoms. (C)
ÎAll patients with EIA must be advised to stop exercising immediately at the first sign of symptoms because continued exertion causes the attacks to worsen. In addition, all patients should carry epinephrine auto injectors and exercise with a partner who can recognize symptoms and administer epinephrine if necessary. (D)
ÎIn patients with episodes related to eating, the ingestion of food should be avoided for 4 hours prior to exercise.
ÎProphylactic medications are not effective for preventing attacks in the majority of patients, although a small subset does appear to benefit from daily administration of H1 antihistamines. (D)
ÎThe prognosis of patients with EIA is generally favorable, although at least one fatality has been reported. Most patients experience fewer and less severe attacks over time. It is unclear if this is the result of trigger avoidance or a change in the underlying condition. (C)
Idiopathic Anaphylaxis
ÎThe symptoms of idiopathic anaphylaxis are identical to those of episodes related to known causes. (C)
ÎPatients with idiopathic anaphylaxis should receive an intensive evaluation, including a meticulous history to rule out a definite cause of the events. (C)
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