Case Discussion

CASE DISCUSSION ON ANAPHYLAXISElaine V. PunoDefinition: Anaphylaxisa serious, life-threatening generalized or systemic hypersensitivity reaction a serious allergic reaction that is rapid in onset and might cause death.

*World Allergy Organization (WAO), Guidelines for Management for the Assessment and Management of Anaphylaxis, 2012The World Allergy Organization defines anaphylaxis as a serious, life-threatening generalized or systemic hypersensitivity reaction or a serious allergic reaction that is rapid in onset and might cause death.

2Etiology

Anaphylaxis can occur in response to almost any foreign substance. Common triggers include venom from insect bites or stings, foods, and medication. Foods are the most common trigger in children and young adults while medications and insect bites and stings are more common in older adults. Less common causes include: physical factors, biological agents such as semen, latex, hormonal changes, food additives such as monosodium glutamate and food colors, and topical medications. Physical factors such as exercise (known as exercise-induced anaphylaxis) or temperature (either hot or cold) may also act as triggers through their direct effects on mast cells.

In our patient, it was apparent from the history that ingesting chicken was the cause of anaphylaxis.3Clinical ManifestationsAnaphylaxis typically presents many different symptoms over minutes or hours with an average onset of 5 to 30 minutes if exposure is intravenous and 2 hours for foods.The most common areas affected include: skin (8090%), respiratory (70%), gastrointestinal (3045%), heart and vasculature (1045%), and central nervous system (1015%)[5] with usually two or more being involved.

Patients with anaphylaxis may present with symptoms shown above5

*Tang et al. A Practical Guide to Anaphylaxis. American Academy of Family Physicians, 2003The most common symptoms of anaphylaxis are seen above with skin, respiratory and CNS manifestations predominating.

*Tang et al. A Practical Guide to Anaphylaxis. American Academy of Family Physicians, 20036

Going back to our patient, it can be recalled from the history that the following symptoms were manifested: urticaria/angiodema, syncope, hypotension (?) and flushing7

Clinical Criteria for Diagnosing Anaphylaxis*World Allergy Organization (WAO), Guidelines for Management for the Assessment and Management of Anaphylaxis, 2012In the present case, there was generalized urticaria and flushing occurring within minutes after the patient ingested chicken and there were associated symptoms of end-organ dysfunction, manifesting as syncope. Hence, it can be concluded that the patient fulfills clinical criteria #1

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*World Allergy Organization (WAO), Guidelines for Management for the Assessment and Management of Anaphylaxis, 2012Clinical Criteria for Diagnosing AnaphylaxisIn the present case, there was generalized urticaria and flushing occurring within minutes after the patient ingested chicken and there were associated symptoms of end-organ dysfunction, manifesting as syncope. Hence, it can be concluded that the patient fulfills clinical criteria #19Management of AnaphylaxisEarly recognition of anaphylaxis is important since death occurs within minutes to hoursAdminister 0.3 to to 0.5 mL of 1:1000 (1 mg/mL) epinephrine SC or IM, with repeated doses as required at 5-10 min intervals.*IV infusion should be initiated to provide a route for administration of epinephrineVolume expanders (e.g. normal saline) & Vasopressor agents (i.e. Dopamine) if intractable hypotension occurs.* Harrisons Principles of Internal Medicine, 18th ed10Management of AnaphylaxisOxygen via a nasal catheter may be helpfulEndotracheal intubation or tracheostomy is mandatory for oxygen delivery if progressive hypoxia developsAntihistamine diphenhydramine, 50-100 mg IM or IV, for urticaria & angiodemaAminophylline 0.25-0.5 g IV may be given for bronchospasmIntravenous glucocorticoids (medrol 0.5-1 mg/kg) are not effective for the acute event but may alleviate later recurrence of bronchospasm, hypotension or urticaria

* Harrisons Principles of Internal Medicine, 18th ed

*World Allergy Organization (WAO), Guidelines for Management for the Assessment and Management of Anaphylaxis, 2012Here is a simplified guideline in managing Anaphylaxis as provided by the World Allergy Organization (WAO)12

*World Allergy Organization (WAO), Guidelines for Management for the Assessment and Management of Anaphylaxis, 2012ReferencesHarrisons Principles of Internal Medicine, 18th ed, 2012World Allergy Organization (WAO), Guidelines for Management for the Assessment and Management of Anaphylaxis, 2012Tang et al. A Practical Guide to Anaphylaxis. American Academy of Family Physicians, 2003

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