A case-control study for comorbidity and laboratory factors associated with food-induced anaphylaxis.

Background: Food-induced anaphylaxis (FIA) is a serious and potentially life-threatening allergic reaction triggered by food allergens. Objective: This case-control study aimed to investigate comorbidities and laboratory factors associated with FIA in the pediatric population of Israel. Methods: Retrospective data from the electronic health records of Leumit Health Care Services were used to identify 711 pediatric patients with FIA and 2560 subjects with food allergy and without anaphylaxis matched for age, gender, and ethnicity. Comorbidities were identified based on medical billing diagnosis codes, and laboratory characteristics were compared between the two groups. Results: The mean ± standard deviation age of patients with FIA was 4.1 ± 4.1 years, and 37.3% were girls. Laboratory analysis revealed increased eosinophil counts (p < 0.001), elevated immunoglobulin E (IgE) (p < 0.001), and IgA levels (p = 0.001) in the FIA group compared with the controls. With regard to comorbidities, the FIA group had higher prevalence rates of allergic diseases, including allergic rhinitis (odds ratio [OR] 1.72; p < 0.001), allergic conjunctivitis (OR 1.84; p = 0.001), asthma (OR 1.36; p < 0.001), angioedema (OR 6.37; p < 0.001), atopic dermatitis (OR 1.77; p < 0.001), and contact dermatitis (OR 1.42; p = 0.001). There was a trend toward significance for chronic spontaneous urticaria (p = 0.051). There was a significant negative association between helminthiases, particularly enterobiasis, and FIA (OR 0.76 [95% confidence interval, 0.59-0.98]; p = 0.029). Conclusion: This study provides valuable epidemiologic evidence on the associations among FIA, comorbidities, and laboratory factors in the pediatric population.

A comparative study of chronic spontaneous urticaria and chronic mast cell mediated angioedema.

Background: Mast cell-mediated angioedema (MC-AE) is considered a form of chronic spontaneous urticaria (CSU). Objective: To investigate the clinical and laboratory features that distinguish MC-AE from antihistamine-responsive CSU (CSU), and antihistamine-resistant CSU (R-CSU) with and without concomitant AE. Methods: A retrospective observational study using the electronic patient record data base of patients with MC-AE, CSU, R-CSU, and sex- and age-matched control group (control), with a case-control ratio of 1:2. Results: A total of 986 subjects in the CSU group, 148 in the R-CSU group, 64 in the MC-AE group, and 1198 in the control group were compared. The R-CSU group without AE was characterized by lower total IgE levels (118.5 ± 84.7 IU/mL) and higher High sensitivity-C reactive protein (hs-CRP) levels (138.9 ± 94.2 IU/mL, p = 0.027; and 7.4 ± 6.9 mg/L versus 5.1 ± 6.8 mg/L, p = 0.001) than the CSU without AE group. The R-CSU group with AE was characterized by lower total IgE levels (112.1 ± 81.3 IU/mL) than the CSU group with AE (141.7 ± 89.5 IU/mL; p < 0.001), higher hs-CRP levels (7.1 ± 6.1 mg/L versus 4.7 ± 5.9 mg/L; p < 0.001). There were fewer female subjects in the MC-AE group (31 [48.4%]) than in the CSU with AE and in the R-CSU with AE 223 (67.8%) and 18 (66.7%), respectively; p = 0.012). MC-AE group was characterized by less eyelid/perioral/facial involvement and more limb involvement than in the CSU with AE and R-CSU with AE groups (p < 0.001). Conclusion: Low IgE in MC-AE and higher IgE in CSU may signify two distinct types of immune dysregulation. Due to clinical and laboratory differences between MC-AE and CSU, we suggest questioning the assumption that MC-AE is a form of CSU.

Case of benralizumab-induced exacerbations of chronic spontaneous urticaria.

The role of IL-5 in chronic spontaneous urticarial (CSU) is unclear. It may be that benralizumab is an important bidirectional modifier of CSU; that is, blocking IL-5 may improve CSU in some patients, but it is possible that it may worsen CSU in others.