Case history
Case history #1
A 14-year-old girl presents in severe respiratory distress to the emergency department. Her past medical history includes asthma and a peanut and tree nut allergy. Shortly after ingestion of a cookie in the school cafeteria, she began complaining about flushing, pruritus, and diaphoresis followed by throat tightness, wheezing, and dyspnea. The school nurse called emergency services. No medications were administered and the patient did not have an epinephrine (adrenaline) auto-injector prescribed by her allergist. Her physical examination reveals audible wheezing and laryngeal edema and an oxygen saturation of 92%.
Case history #2
A 65-year-old man reports being stung while working in his garden. He removed the stinger and found the dying bee. In the past he tolerated insect stings on several occasions without reaction. On this occasion, within minutes, he experienced flushing, sweating, and a brief loss of consciousness. Too confused to call for help, he was found 10 minutes later by his wife. Emergency services were called and on arrival of the ambulance he was rousable, without respiratory distress or rash. Systolic BP was 75 mmHg and pulse rate was 55 bpm.
Other presentations
A patient may follow a biphasic time course, or the presentation may be atypical and limited to a single organ system (e.g., only laryngeal edema or gastrointestinal symptoms after shellfish ingestion). Biphasic reactions describe the recurrence of symptoms after resolution of the initial episode and can occur up to 78 hours after the event, with the majority occurring at 8 to 10 hours. The severity of symptoms is highly variable, with about one third more severe, one third severe, and one third less severe. Anaphylaxis may also occur with no previously known exposure to the allergen, particularly in older adults. The risk of sensitization to peanut among children exposed to peanut allergens through breastfeeding is the subject of ongoing research.[3][4][5] Simple hypotension after drug administration may represent the beginning of severe anaphylaxis (e.g., radioiodine allergy or secondary to some neuromuscular blockers).
Use of this content is subject to our disclaimer