Tolerance of peanuts and tree nuts in Spanish children with exclusive sensitization to lipid transfer proteins.

BACKGROUND: Allergy to peanuts and tree nuts is a common cause of food allergy in Spain, with lipid transfer proteins (LTP) being the most frequently recognized panallergen. LTP sensitization often leads to multiple food group sensitivities, resulting in overly restrictive diets that hinder patient's quality of life. This study aimed to assess the tolerance of peanuts and tree nuts (hazelnuts and walnuts) in children sensitized to LTP, potentially mitigating the need for such diets. METHODS: This prospective study enrolled individuals diagnosed with allergy to peanuts, hazelnuts, or walnuts. Data were collected from medical records, including demographics and clinical history. Allergological assessment comprised skin prick tests using commercial extracts and the nuts in question, alongside measurements of total and specific IgE to nuts and their primary molecular components. Participants showing positive LTP sensitization without sensitization to seed storage proteins underwent open oral nut challenges. RESULTS: A total of 75 individuals labeled as allergic to peanuts, 44 to hazelnuts, and 51 to walnuts were included. All of them underwent an open oral provocation test with the incriminated nut, showing a high tolerance rate. Peanut was tolerated by 98.6% of patients, 97.72% tolerated hazelnut, and 84.3% tolerated walnut. CONCLUSION: The findings suggest that the majority of patients allergic to peanuts, hazelnuts, or walnuts, due to LTP sensitization and lacking IgE reactivity to seed storage proteins, can tolerate these nuts. This supports the need for personalized nut tolerance assessments to avoid unnecessary dietary restrictions.

Sensitisation to peach allergen Pru p 7 is associated with severe clinical symptoms in a Spanish population.

BACKGROUND: Pru p 7 has been reported as a major allergen in peach allergy, associated with severe clinical symptoms and related to IgE sensitisation to cypress pollen. The main objective of this study was to prospectively evaluate the frequency of sensitisation to Pru p 7 and its clinical relevance amongst pediatric patients with peach allergy in Madrid (Spain). METHODS: Patients with a history of IgE-mediated symptoms (oral allergy syndrome, urticaria/angioedema, rhinoconjunctivitis/asthma, gastrointestinal symptoms, or anaphylaxis) occurring within 2 h after peach intake or contact were prospectively recruited from February 2020 to September 2021. Skin tests, sIgE by ImmunoCAP® (Pru p 1, Pru p 3, Pru p 4, Pru p 7, and Cupressus arizonica) and oral food challenge (OFC) were performed. The study was approved by the local Ethics Committee (PI-4513). RESULTS: Ninety-two patients were included (53.3% male); median age, 10 (IQR 6.0-14.75) years. Seventy-four (80.4%) patients had a reaction after ingestion of fresh peach (25.0% from peel, 23.9% from pulp, and 44.6% from both). Fifteen (16.3%) patients were sensitised to Pru p 7. Upper airway symptoms, anaphylaxis, and grade 2 reactions were statistically more frequent in patients sensitised to Pru p 7. Seven (7.9%) patients presented with exercise as a cofactor, four of whom were sensitised to Pru p 7 (p = .001). Patients sensitised to Pru p 7 were significantly more likely to have a positive OFC result than patients who were not (p = .008). Four patients who reacted to peach at OFC were sensitised to Pru p 7. Specific IgE against Cupressus arizonica pollen was positive in 25 (62.5%) patients. CONCLUSIONS: Pru p 7 sensitisation was observed in 16.3% of our population and was related to severe reactions, upper airway symptoms, anaphylaxis, and the presence of an eliciting cofactor.

Drug Provocation Tests for Assessing Antibiotic Hypersensitivity: Is Shorter Also Better?

BACKGROUND: Suspected antibiotic hypersensitivity in children is a frequent reason for consultation. Skin test performance and drug provocation test (DPT) duration are controversial issues. The objective of this study was to assess the effectiveness of diagnostic tests used in the study of antibiotic hypersensitivity and to estimate an optimal duration for DPT. METHODS: Sixty-two children with a suspected hypersensitivity reaction to antibiotics were studied. Skin tests were performed on all patients. In the case of negative results, DPTs were performed for a duration similar to the time elapsed from the start of treatment until the onset of the reaction. RESULTS: The frequency of antibiotic hypersensitivity in the study population was 8.1% (5 of 62). Only 1 patient showed positive skin tests. The other allergic patients were diagnosed by DPT, which reproduced the reaction within the first 6 hours in all but one of them. CONCLUSIONS: Shortening DPT duration may decrease the sensitivity of the test for the diagnosis of non-IgE-mediated hypersensitivity; however, it should be considered as an opportunity to reduce the resulting microbial resistances.

Prospective assessment of diagnostic tests for pediatric penicillin allergy: From clinical history to challenge tests.

BACKGROUND: Diagnostic guidelines for penicillin allergy in children recommend cumbersome protocols based partially on data from adults, which may be suboptimal for pediatric use. OBJECTIVE: To assess the accuracy of tools for diagnosis of penicillin allergy in children. METHODS: A prospective, multicenter study was conducted in children with reported adverse events related to penicillin, excluding severe reactions. All patients underwent a uniform diagnostic protocol that consisted of clinical history, skin tests, serum specific IgE (sIgE), and, regardless of these results, drug provocation tests (DPTs). RESULTS: A total of 732 children (mean age, 5.5 years; 51.2% males) completed the allergy workup, including DPTs. Amoxicillin triggered 96.9% of all reactions. None of the patients with an immediate index reaction (IR) developed a reaction on DPT. Penicillin allergy was confirmed in 35 children (4.8%): 6 immediate reactions (17%) and 29 nonimmediate reactions (83%) on the DPT. No severe reactions were recorded. The allergist diagnosis based on the clinical history was not associated with the DPT final outcome. In 30 of 33 allergic patients (91%), the results of all skin tests and sIgE tests were negative. A logistic regression model identified the following to be associated with penicillin allergy: a family history of drug allergy (odds ratio [OR], 3.03; 95% confidence interval [CI], 1.33-6.89; P = .008), an IR lasting more than 3 days vs 24 hours or less (OR, 8.96; 95% CI, 2.01-39.86; P = .004), and an IR treated with corticosteroids (OR, 2.68; 95% CI, 1.30-5.54; P = .007). CONCLUSION: Conventional predictors of allergy to penicillin performed weakly. The authors propose straightforward penicillin provocation testing in controlled, experienced centers for the diagnosis of nonsevere penicillin allergy in children.

Psychometric Field Study of Hereditary Angioedema Quality of Life Questionnaire for Adults: HAE-QoL.

BACKGROUND: Hereditary angioedema due to C1 inhibitor deficiency (C1-INH-HAE) may affect health-related quality of life (HRQoL). A specific HRQoL questionnaire for adult patients with C1-INH-HAE, the HAE-QoL, has recently been developed in Spain. OBJECTIVE: The objective of this study was to perform a cross-cultural validation and psychometric study of the HAE-QoL in an international setting. METHODS: Cross-cultural adaptation of the Spanish HAE-QoL draft version and an international rating phase with experts were performed. The resultant version of the HAE-QoL, a clinical questionnaire, and Short Form 36-item Health Survey Version 2.0 (SF-36v2) were pilot tested internationally. Item reduction was based on both descriptive and exploratory factor analysis. Psychometric properties were assessed. RESULTS: Cross-cultural adaptation of the HAE-QoL was performed in 18 countries. The draft version of the HAE-QoL was pilot tested in 332 patients, and accurate data were obtained from 290 patients from 11 countries. The reduction process resulted in a new version with 25 items and 7 dimensions (treatment difficulties, physical functioning and health, disease-related stigma, emotional role and social functioning, concern about offspring, perceived control over illness, and mental health). Strong psychometric properties were observed (Cronbach's α 0.92; test-retest reliability 0.87). Convergent validity showed mild to moderate correlations with SF-36v2 physical and mental component summaries (0.45 and 0.64, respectively) and with SF-36v2 dimensions (P < .004). HAE-QoL scores discriminated significantly among severity groups (median: asymptomatic 133.5 vs severe 84.0; P < .001); between patients with and without long-term prophylaxis (median: 101 vs 90; P = .001); and between patients with and without psychiatric and/or psychological care (median: 74 vs 103; P ≤ .001). CONCLUSIONS: The HAE-QoL, currently available in 18 languages, showed good reliability and validity evidence.

Paracetamol-induced fixed drug eruption at an unusual site.

BACKGROUND: Paracetamol (acetaminophen) is a widely used analgesic/antipyretic drug for which hypersensitivity reactions appear to be increasingly frequent. OBJECTIVE: We report the case of a woman who experienced several delayed selective reactions induced by paracetamol: fixed drug eruptions (FDEs) with typical features but an unusual distribution (hard palate and a maculopapular rash. METHODS: Skin tests: prick, intradermal and patch tests as well as a single-blind oral challenge test (OCT) were performed. RESULTS: Skin tests were negative. The OCT was necessary to confirm the diagnosis. Interestingly, the challenge test elicited an FDE-type lesion instead of a maculopapular rash. CONCLUSIONS: Our findings could reflect 2 different clinical patterns of delayed allergic reactions, or, more probably, the initial phase of a unique clinical entity that was stopped by the corticosteroids prescribed during the challenge. However, we were unable to confirm these hypotheses. The uncommon anatomical site of the lesions (hard palate) is noteworthy. Some relevant patents are also summarized in this paper.

Development of a disease-specific quality of life questionnaire for adult patients with hereditary angioedema due to C1 inhibitor deficiency (HAE-QoL): Spanish multi-centre research project.

BACKGROUND: There is a need for a disease-specific instrument for assessing health-related quality of life in adults with hereditary angioedema due to C1 inhibitor deficiency, a rare, disabling and life-threatening disease. In this paper we report the protocol for the development and validation of a specific questionnaire, with details on the results of the process of item generation, domain selection, and the expert and patient rating phase. METHODS/DESIGN: Semi-structured interviews were completed by 45 patients with hereditary angioedema and 8 experts from 8 regions in Spain. A qualitative content analysis of the responses was carried out. Issues raised by respondents were grouped into categories. Content analysis identified 240 different responses, which were grouped into 10 conceptual domains. Sixty- four items were generated. A total of 8 experts and 16 patients assessed the items for clarity, relevance to the disease, and correct dimension assignment. The preliminary version of the specific health-related quality of life questionnaire for hereditary angioedema (HAE-QoL v 1.1) contained 44 items grouped into 9 domains. DISCUSSION: To the best of our knowledge, this is the first multi-centre research project that aims to develop a specific health-related quality of life questionnaire for adult patients with hereditary angioedema due to C1 inhibitor deficiency. A preliminary version of the specific HAE-QoL questionnaire was obtained. The qualitative analysis of interviews together with the expert and patient rating phase helped to ensure content validity. A pilot study will be performed to assess the psychometric properties of the questionnaire and to decide on the final version.

Usefulness of abdominal ultrasonography in the follow-up of patients with hereditary C1-inhibitor deficiency.

BACKGROUND: Hereditary angioedema (HAE) is caused by the deficiency of functional C1 inhibitor. Symptoms of this disease include cutaneous angioedema, abdominal pain, and even laryngeal edema. OBJECTIVE: To evaluate the usefulness of abdominal ultrasonography in patients with hereditary C1-inhibitor deficiency in diagnosing acute abdominal edema attacks and possible adverse effects of long-term prophylaxis with attenuated androgens. METHODS: Fifty-nine adult patients with HAE regularly observed in our department were included whether they were symptomatic or not and whether they received long-term androgen prophylaxis or not. We evaluated the ultrasonographic findings in the assessments performed routinely or in the moment of an acute abdominal attack. RESULTS: Of the 59 patients, 55 ever had any symptom due to HAE (abdominal location, 78% of the symptomatic patients); 4 patients were asymptomatic. In 11 cases, ultrasonography was performed during acute attacks. Ascites and intestinal wall swelling were found in 7 of these 11 cases and, thus, diagnosis was confirmed. Of the 59 patients, 33 were or had been receiving androgen prophylaxis. Abdominal ultrasonographic assessments were performed routinely in 31 of these patients. Four cases of angiomas, 4 of steatosis, and 1 each of portal hypertension, hepatic cysts, and hepatomegaly were found. Assessments were also performed in 17 patients who did not receive androgen prophylaxis; there were no findings in any of these patients. CONCLUSION: Abdominal ultrasonography has been proved useful as an early tool for diagnosing the adverse effects of therapy and for confirming diagnosis in the case of an acute abdominal attack.