Prognosis of food-induced anaphylaxis in children: A single-center real-life study

Background: Food allergies are known to resolve over time, but there is little information on the natural history of food-induced anaphylaxis (FIA). Objective: This study aimed to evaluate the natural history of FIA in children and determine the factors that affect prognosis. Methods: Children with FIA who were followed up for at least 3 years, between 2010 and 2020, were included. Patients' families were contacted by telephone to question their child's tolerance status and invite them for reevaluation if uncertain. The patients were grouped as tolerant or persistent according to parent reports or reevaluation results. Logistic regression analysis was performed to determine the factors that affected persistence. Results: The study included 185 patients (62.2% boys) with 243 anaphylactic reactions to various foods. Fifty-eight patients (31%) gained tolerance within a 3-year follow-up period. Tolerance rates were higher in patients with FIA to milk (40%) and egg (43.9%) compared with to tree nuts (18.8%), legumes (5.6%), and/or seafood (11.1%) (p < 0.001). In a multivariate analysis, risk factors for persistent FIA were multiple food anaphylaxis (odds ratio [OR] 3.755 [95% confidence interval {CI}, 1.134‐12.431]; p = 0.030), total IgE > 100 kU/L (OR 5.786 [95% CI, 2.065‐16.207]; p = 0.001), and skin-prick test wheal size > 10 mm (OR 4.569 [95% CI, 1.395‐14.964]; p = 0 .012) at presentation. Conclusion: Approximately a third of the patients with FIA developed tolerance within 3 years. Clinicians should remember that children with food allergies, even anaphylaxis, may develop tolerance over time. Regular follow up and reevaluation of tolerance status are necessary to avoid unnecessary elimination.

Adjunct therapy with probiotics for chronic urticaria in children: randomised placebo-controlled trial

Backgrounds Chronic urticaria is a common disorder of the skin, characterised by recurrent skin wheals and angioedema. Recent reports have shown that altered diversity and composition of the gut microbiota may lead to imbalances in immune regulation, a causal factor in the occurrence of chronic urticaria. Objective This study aimed to evaluate the efficacy of the Yimingjia® probiotic formula in the adjuvant treatment of chronic urticaria in children. Methods We enrolled 206 children with confirmed diagnoses of chronic urticaria and randomly assigned them to the treatment (n = 104) or placebo group (n = 102). The children in each group were treated with desloratadine dry suspension, and those in the treatment group also received Yimingjia®. Clinical efficacy was evaluated at 1, 2 and 4 weeks. Results Clinical symptom scores did not differ significantly at weeks 1 and 2 (p > 0.05), but at 4 weeks, wheal size and attack frequency were significantly reduced in the treatment group (p = 0.049 and 0.03, respectively). The overall response rate (significant improvement + complete response) significantly differed between the treatment (80.8%) and placebo groups (62.5%) (χ2 = 4.20, p = 0.04). Conclusion Adjunct therapy with Yimingjia® was safe and effective at 4 weeks in the treatment of chronic urticaria in children. The study was registered under trial number NCT03328897.

Comparative Efficacy of Fexofenadine Versus Levocetrizine Versus Desloratadine via 1% Histamine Wheal Suppression Test

Background Urticaria and allergic dermatoses remains a great challenge to treating dermatologist. Histamine is the major mediator in such disorders. Antihistamines as levocetrizine, fexofenadine and desloratadine are often used to treat such conditions. Ability of antihistamines to suppress the allergic response helps to evaluate the efficacy of the medicine. Objective To compare the efficacy of levocetrizine versus fexofenadine versus desloratadine in suppressing histamine induced wheals in adults. Method One hundred and two healthy adult volunteers completed the study. Subjects were randomized into 3 groups using an envelope method. First group received fexofenadine (N=36), second group received levocetrizine (N =37), and third group received desloratadine (N=29). Pretesting was performed by skin prick test with histamine 1% (positive control) and normal saline (negative control). Wheal size was recorded before and after the treatment (at 0.5, 1, 2, 4 and 24 hours). Result At 30 minutes and 1 hour fexofenadine showed statistically significant wheal suppression than levocetrizine and desloratadine (p=0.0016). However by 2 and 4 hours all three antihistamines; fexofenadine, levocetirizine and desloratadine showed significant suppression of wheal. Whereas at 24 hours desloratadine showed greater wheal suppression than levocetrizine and fexofenadine (p= 0.014). Conclusion The results of the present study showed that fexofenadine presented early onset of action but longer suppression of wheal size was seen with desloratadine as compared to other antihistamines. These potentials could be employed in clinical aspects; depending upon the response needed.

Low Potency of Indian Dust Mite Allergen Skin Prick Test Extracts Compared to FDA-Approved Extracts: A Double-Blinded Randomized Control Trial

Background Skin prick testing is the most important diagnostic tool to detect immunoglobulin E-mediated allergic diseases. With increase in the number of allergy tests performed in India, it is imperative to know the potency of indigenous extracts in comparison with U.S. Food and Drug Administration (USFDA)-approved extracts. Methods A randomized comparison trial of Indian manufactured and USFDA-approved extracts of Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF) was done at Christian Medical College & Hospital, Vellore, India from April 2014 to June 2015, to compare the skin test reactivity of indigenous allergen extracts of dust mites against validated allergen. Study enrollment included 197 patients with allergic disorders that showed sensitivity to dust mite during routine allergy skin testing. Study participants were tested with varying dilutions of DP and DF indigenous extracts along with USFDA-approved allergens in a blinded fashion. Results were recorded, and statistical significance was calculated using the Friedman rank sum test. Results Using the Friedman rank sum test with a Tukey adjustment for multiple comparisons, we found that the extracts in each dilution were significantly different ( P < .0001). The full strength indigenous extracts, B-DF (DF allergen standard extract from Bioproducts and Diagnostics, India) and C-DF (DF allergen extract from Creative Diagnostics, India) extracts, had mean wheal sizes of 7.69 (standard deviation [SD] 9.91) and 31.01(SD 51.04), respectively. The full strength S-DF (DF allergen extract from Jubilant Hollister Stier, Spokane, WA, USA) had a mean wheal size of 109.97 (SD 162.73), which was significantly higher ( P < .0001) than both the indigenous extracts. For each of the dilutions, the S-DF mean wheal size was significantly greater than that of the corresponding B-DF and C-DF wheal sizes. The full strength indigenous C-DP (DP allergen extract from Creative Diagnostics, India) had mean wheal size of 39.37 (SD 51.74). The full strength standard S-DP (DP allergen extract from Jubilant Hollister Stier, Spokane, WA, USA) extract had a mean wheal size of 167.66 (SD 270.80), which was significantly higher ( P < .0001) than the indigenous C-DP extract. Similar differences were seen across all dilutions. Conclusion The indigenous extracts have significantly lower potency compared to USFDA-approved extracts; hence, there is an urgent need for policy makers to institute stringent criteria for standardization of antigens in India.

Evaluation of the Skin-prick Test for Predicting the Outgrowth of Cow's Milk Allergy

Background Although considerable efforts have been made to develop diagnostic tools for predicting the outcome of oral food challenges, tests for predicting the outgrowth of food allergies are lacking. Objective The aim of this study was to assess the diagnostic value of the wheal size and skin index (SI) (the ratio of an allergen-induced wheal to a histamine-induced wheal diameter) of the skin-prick test based on the outcome of a controlled oral provocation test for cow's milk. Moreover, we assessed whether wheal size and/or SI were useful for predicting the outgrowth of cow's milk allergy (CMA). Methods This study included 135 children with suspected CMA. Eighty-one patients were definitely diagnosed by oral provocation tests for cow's milk, and their wheal diameters, SIs, and cow milk's–specific serum immunoglobulin E concentrations were determined. Results The wheal diameters were significantly larger and the SIs significantly higher in children with positive oral provocation test results than in those with negative test results. We found that 50% of the patients were expected to be able to drink cow's milk by age 5 years. In these patients, the wheal diameters were significantly smaller and the SIs significantly lower at the time of CMA outgrowth than at the time of diagnosis, whereas these values were apt to increase in patients who did not outgrow CMA, with no significant difference. Conclusions The skin-prick test can be used to diagnose CMA and predict CMA outgrowth. A wheal diameter of 8 mm or/and an SI of 1.0 is informative, not only in diagnosing CMA but also in predicting a natural CMA outgrowth.

Egg Baked in Product Open Oral Food Challenges are Safe in Selected Egg-Allergic Patients

Egg allergy is one of the most common food allergies in children. Most egg-allergic children are able to tolerate egg baked in product (EBP) and will likely outgrow his/her egg allergy. By introducing EBP in the diet of an egg-allergic child, diet can be expanded and family stress can be reduced. Recent evidence suggests that children who tolerate EBP and continue to consume it will have quicker resolution of egg allergy than those who strictly avoid EBP; therefore, we aimed to evaluate the egg-allergic children who underwent EBP oral food challenge (OFC) in our allergy clinic to help define any specific predictors to be used in predicting the outcome of such challenges. We performed a retrospective chart review and 43 egg-allergic patients underwent EBP OFC in our outpatient allergy office from January 2011 to December 2012 were excluded. Nine patients who did not have a prior history of symptomatic egg ingestion. Clinical characteristics and laboratory findings of the remaining 34 patients were all recorded and analyzed. Of the remaining 34 patients, 22 (64.7%) were boys. Average age of first reaction to egg was 12.90 months, with average age at EBP OFC of 71.32 months. The average of the most recent skin-prick test wheal size was 10.10 mm and serum-specific IgE to egg white was 3.21 kU/L. Twenty-eight of the 34 patients (82.4%) passed the EBP OFC. Of the six patients who failed, none required epinephrine. After analysis of all of the clinical characteristics and laboratory findings, no risk factors, such as skin-prick test wheal size, were identified to be associated with an increased risk of failing EBP OFC. EBP OFC is a valuable tool to assess tolerance. As seen in our group of patients, the majority of egg-allergic patients pass EBP OFC. Thus, OFC should be considered as a clinical tool to expand a patient's diet and to improve quality of life as early as possible. Because we were unable to determine any clinical or laboratory predictors helpful to select egg-allergic patients who are likely to pass EBP OFC, additional prospective studies are necessary to determine the ideal egg-allergic patient who is likely to pass EBP OFC.