Urticaria, Angioedema, and Anaphylaxis

Urticaria and, to a lesser extent, angioedema are common occurrences in the pediatric population. There are multiple causes of acute and chronic urticaria and angioedema. Most causes are benign, although they can be worrisome for patients and their parents. An allergist should evaluate acute urticaria and/or angioedema if there are concerns of an external cause, such as foods or medications. Chronic urticaria and angioedema can severely affect quality of life and should be managed aggressively with antihistamines and immunomodulators if poorly controlled. Chronic symptoms are unlikely to be due to an external cause. Anaphylaxis is a more serious allergic condition characterized by a systemic reaction involving at least 2 organ systems. Anaphylaxis should be initially managed with intramuscular epinephrine. Patients who experience anaphylaxis should be evaluated by an allergist for possible causes; if found, avoidance of the inciting antigen is the best management. All patients should also be given an epinephrine autoinjector and an action plan. Foods are a common cause of anaphylaxis in the pediatric population. New evidence suggests that the introduction of highly allergic foods is safe in infancy and should not be delayed. In addition, the early introduction of foods such as peanuts may help prevent the development of food allergies

Diagnostic Challenges in Anaphylaxis

Anaphylaxis is a severe and potentially life-threatening allergic reaction. Since its discovery over 100 years ago, research has led to great strides in describing pathophysiologic mechanisms of anaphylaxis; however, there is still imprecision regarding its definition and a lack of reliable, confirmatory testing. In this paper, we review definitions of anaphylaxis, highlighting studies examining the utility of the current clinical consensus definition. In addition, we evaluate current difficulties and limitations for both providers in acute care settings managing episodes and allergists evaluating patients after an episode has resolved. Finally, we provide an algorithm for outpatient evaluation of patients with a history of possible anaphylaxis

Food Protein-Induced Enterocolitis Syndrome

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy that usually presents in infancy. Cow\u27s milk, soy, and grains are the most common food triggers. FPIES can present as a medical emergency with symptoms including delayed persistent emesis or diarrhea that can lead to severe dehydration and hemodynamic instability with abnormal laboratory markers. Diagnosis can often be made based on clinical history and noted improvement in symptoms once the suspected triggers have been removed from the diet, with oral food challenge as the gold standard for confirmation of diagnosis in unclear cases

Efficacy of epinephrine and diphenhydramine rinses in decreasing local reactions to subcutaneous aeroallergen immunotherapy

Background: Although local reactions (LR) to subcutaneous immunotherapy (SCIT) occur in 26-86% of patients, there are no well-studied strategies to manage LRs. Objective: To complete a prospective, randomized, single-blind, controlled trial that compared pre-rinsing SCIT syringes with diphenhydramine, epinephrine, or placebo in patients who were receiving aeroallergen SCIT and experiencing LRs despite pretreatment with an antihistamine. Methods: Patients ages ≽5 years who were receiving aeroallergen SCIT per a conventional dosing schedule and who were experiencing LRs despite premedicating with an oral antihistamine were randomized to diphenhydramine, epinephrine, or placebo rinse, and were followed up for three subsequent visits. At each visit, the patients were asked (yes or no) if LRs improved. Results: A total of 490 patients were enrolled in the study. Seventy-four of the 490 patients (15.1%) experienced an LR despite pretreatment with an oral antihistamine and were randomized into an intervention group. At visit 1, an epinephrine rinse was strongly associated with decreasing LR compared with both diphenhydramine rinse and placebo (p \u3c 0.001). There was no difference among the intervention groups at visits 2 and 3. In patients who reported a consistent outcome at all three visits, the epinephrine rinse was significantly associated with a decrease in LR compared with both diphenhydramine rinse and placebo rinse (p = 0.05). Conclusion: In patients who received aeroallergen SCIT per a conventional dosing schedule, an epinephrine rinse significantly decreased LR at the first visit, and also within a population that reported a consistent outcome at all three study visits. In patients already premedicating with an oral antihistamine, adding an epinephrine rinse is a safe and effective strategy to decrease LRs to aeroallergen SCIT