RESUMO
BACKGROUND: Lupin is a protein-rich legume with a growing presence in the food market worldwide. With increased consumption, lupin allergy (LA) reports are also rising. Uncertainties exist on the cross-reactivity between peanut and lupin, the allergenic potential of different lupin species, and sensitization patterns among different populations. OBJECTIVE: To evaluate the molecular basis of LA and to determine lupin allergens from 3 different species that may be involved in peanut allergy (PA) cross-reactivity. METHODS: A total of 43 subjects with PA, those with LA, or controls without food allergy were evaluated with skin prick tests (SPTs) and specific IgEs (sIgEs). Lupin-sensitized subjects were offered a lupin oral food challenge (OFC). Immunoblots and enzyme-linked immunosorbent assays were performed on sera from lupin-sensitized subjects. RESULTS: In this study, 44% of the PA subjects were confirmed to have LA by OFC. Anaphylaxis was the most frequent manifestation after lupin consumption, with a minimal eliciting dosage of 1 g lupin flour. There was no difference in lupin sIgE or SPT wheal size between lupin-sensitized and confirmed LA subjects or in the severity of symptoms among confirmed LA subjects. Sera from lupin-sensitized subjects uniformly reacted to all 3 different lupin species. Immunoblotting and enzyme-linked immunosorbent assays revealed immunoglobulin E binding to α- and γ-conglutin in all analyzed sera, whereas α- and ß-conglutin recognition was variable. CONCLUSION: Our findings reveal a high prevalence of LA among PA subjects, emphasizing lupin must be labeled as an allergen in foods. Owing to high variability in lupin-sIgE and lupin-SPT results, LA diagnosis may require OFC. In our population, γ-conglutin is the major allergen of lupin.
Assuntos
Hipersensibilidade Alimentar , Lupinus , Hipersensibilidade a Amendoim , Humanos , Hipersensibilidade a Amendoim/diagnóstico , Hipersensibilidade a Amendoim/epidemiologia , Alérgenos , Prevalência , Imunoglobulina E , Lupinus/efeitos adversos , Arachis , Testes Cutâneos/métodosRESUMO
Food allergy prevalence is increasing worldwide, therefore there is a high demand for reliable tests to correctly diagnose this disease. Knowledge of proteins allergenicity and how they react both in the body and in diagnostic tests is necessary to adequately assess the potential immunogenicity of both natural foods and those produced through biotechnological processes. Thus, our aim was to analyze the factors that influence the protein extraction of foods in terms of, immunogenicity and immunoassays sensitivity. Peanut proteins were extracted using four distinct extraction buffers with different pH values (physiological saline, tris buffer, borate buffer with and without ß-mercaptoethanol), the protein concentration was determined by the Lowry method and polyacrylamide electrophoresis (SDS-PAGE) was used to compare the protein profile of each extract. The immunogenicity of each extract was verified by sensitizing two mouse strains (Balb/c and C57Bl/6) with a solution containing 100 µg of the extracted proteins and was determined by ELISA. Results show that extraction with the distinct buffers resulted in protein solutions with different yields and profiles. The immunogenicity of the different extracts also demonstrated distinct patterns that varied depending on the extraction methods, mouse strain and in vitro test. Immunoreactivity varied in accordance with the protein extract used to coat the microtitration plates. In conclusion, the protein profile in the extracts is critically influenced by the salt composition and pH of the extraction buffers, this in turn influences both in vivo immunogenicity and in vitro immunoreactivity.
Assuntos
Alérgenos/imunologia , Alérgenos/isolamento & purificação , Arachis/imunologia , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/sangue , Hipersensibilidade a Amendoim/diagnóstico , Proteínas de Plantas/imunologia , Proteínas de Plantas/isolamento & purificação , Alérgenos/administração & dosagem , Animais , Biomarcadores/sangue , Soluções Tampão , Fracionamento Químico , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Concentração de Íons de Hidrogênio , Injeções Subcutâneas , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Hipersensibilidade a Amendoim/imunologia , Proteínas de Plantas/administração & dosagem , Valor Preditivo dos Testes , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Peanut allergy among adults with respiratory diseases has seldom been studied within Mexico. OBJECTIVE: To establish the prevalence of peanut allergy among adults that have been diagnosed with either asthma or allergic rhinitis; we will also be describing the symptoms that are associated with peanut allergy. METHODS: We carried out a cross-sectional study through which we analyzed the corresponding data of 257 patients with allergic respiratory diseases, asthma or allergic rhinitis, all participants were 16 years of age or older, and were recruited in a consecutive manner. Peanut allergy was established by testing positive to a peanut skin-prick test; we also conducted a standard interview with each patient. RESULTS: From our sample of 257 patients, 18 tested positive to peanut sensitization, (7.0%; 95% CI = 3.9% to 10.1%); among these 18 participants, 7 were considered to be allergic to peanuts (2.7%; 95% IC: 0.7% to 4.7%). Predominant symptoms were oral, primarily affecting the pharynx and the palate, followed by swelling of the lips. When it came to respiratory discomfort, sneezing and rhinorrhea stood out, and lastly there were cutaneous symptoms. We did not detect any systemic reactions to the peanut. CONCLUSION: In our study, peanut allergy among adults with allergic respiratory diseases is not an uncommon occurrence.
Antecedentes: La alergia al cacahuate en adultos con enfermedades respiratorias alérgicas pocas veces ha sido estudiada en México. Objetivo: Establecer la prevalencia de alergia al cacahuate en un grupo de adultos con asma o rinitis alérgica; también se describen los síntomas asociados con la alergia al cacahuate. Métodos: Se realizó estudio transversal en el que analizaron los datos correspondientes a 257 pacientes con enfermedades respiratorias alérgicas, asma o rinitis alérgica, con edad igual o mayor a 16 años; los pacientes fueron reclutados consecutivamente. La alergia al cacahuate se determinó por una prueba cutánea positiva al cacahuate y a través de una entrevista estandarizada. Se estimaron intervalos de confianza (IC) a 95 % para proporciones. Resultados: De los pacientes incluidos, 18 estuvieron sensibilizados al cacahuate (7.0 %, IC 95 % = 4.4-10.9), siete de ellos fueron considerados alérgicos al cacahuate, para una prevalencia de 2.7% (IC 95%: 1.2% - 5.6%). En los pacientes con alergia al cacahuate, los síntomas predominantes fueron los orales, principalmente el prurito en la faringe y en el paladar, seguidos de edema de los labios; entre las molestias respiratorias sobresalieron los estornudos y la rinorrea y, al final, los síntomas cutáneos. No se documentaron reacciones sistémicas al cacahuate. Conclusión: En nuestro estudio, la alergia al cacahuate en adultos con enfermedades respiratorias alérgicas no fue infrecuente.
Assuntos
Hipersensibilidade a Amendoim/diagnóstico , Hipersensibilidade a Amendoim/epidemiologia , Adulto , Asma/complicações , Estudos Transversais , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Hipersensibilidade a Amendoim/complicações , Prevalência , Rinite Alérgica/complicações , Adulto JovemRESUMO
31 years old female with a history of contact dermatitis, eczema, allergic rhinitis, pernicious anemia, alopecia areata and latent tuberculosis was treated concurrently with methotrexate along with isoniazid and pyridoxine. Five months into the therapy she developed acute onset jaundice progressing into fulminant liver failure with altered mentation and worsening liver function tests. Extensive workup including serological and histopathological evaluation revealed drug-induced liver injury as the etiology of her liver failure and she underwent a successful orthotropic liver transplant. On post-transplant follow-up at four months, she was noted to have an allergic reaction consisting of a perioral rash and swelling (without anaphylaxis) after receiving a kiss from her significant other who had just eaten a peanut butter chocolate. She denied any history of allergic reaction to peanuts prior to the transplant. Percutaneous skin testing revealed immediate hypersensitivity to peanut, hazelnut, and pecan believed to be acquired newly post-transplant. Further investigation revealed that the organ donor had a documented history of systemic anaphylaxis from the peanut allergy and a positive peanut-specific IgE level. Also, another parallel solid organ recipient (lung transplant) from the same organ donor experienced a serious anaphylactic reaction after peanut exposure. This is a case of food (peanut) allergy transfer from the donor to the recipient after the liver transplant. This case highlights the importance of incorporating known donor allergies as a part of pre-transplant screening, given the potentially serious consequences from the transfer of allergies to a previously anergic recipient.
Assuntos
Transplante de Fígado/efeitos adversos , Hipersensibilidade a Amendoim/etiologia , Doadores de Tecidos , Transplantados , Adulto , Anticorpos Anti-Idiotípicos/imunologia , Feminino , Seguimentos , Humanos , Imunoglobulina E/imunologia , Hipersensibilidade a Amendoim/diagnóstico , Hipersensibilidade a Amendoim/imunologia , Testes CutâneosAssuntos
Hipersensibilidade a Amendoim , Alérgenos , Arachis , Criança , Humanos , Fatores Imunológicos , ImunoterapiaRESUMO
Introdução: Os dados sobre prevalência de alergia alimentar são escassos e limitados no Brasil. Este trabalho objetiva descrever as características clínicas de crianças brasileiras com alergia alimentar diagnosticada através de teste de provocação duplo-cego placebo-controlado (TPDCPC). Métodos: Dos pacientes avaliados, foram selecionadas, de forma prospectiva, no Ambulatório de Alergia e Pneumologia Pediátrica, 234 crianças com suspeita clínica de alergia alimentar e teste alérgico positivo para alimento, no período de 1993 a 2005. Para confirmar o diagnóstico de alergia alimentar, foram realizados TPDCPCs com o alimento suspeito. Resultados: Dos 234 TPDCPCs realizados, 30 foram positivos (12,8%), sendo mais frequentes em crianças abaixo de dois anos e do sexo masculino. Dos testes positivos, 26 (86,6%) foram positivos para ovo ou leite de vaca. Pacientes com diagnóstico inicial de dermatite atópica ou alergia gastrointestinal apresentaram TPDCPC positivo mais frequentemente do que pacientes com sintomas respiratórios. Entre os sintomas apresentados durante o TPDCPC, prevaleceram os sintomas cutâneos (60%) e respiratórios (56,67%). Conclusão: A incidência de alergia alimentar na população com suspeita clínica foi de 12,8%. Leite de vaca e ovo são os principais alimentos responsáveis pela alergia alimentar em nosso meio, que é mais frequente em crianças abaixo de dois anos. O teste alérgico positivo é um fraco preditor de alergia alimentar (VPP = 13,5%), mas o teste alérgico negativo praticamente afasta o diagnóstico, pois o seu valor preditivo negativo na população estudada foi próximo de 100%.
Introduction: Data on the prevalence of food allergy are scarce and limited in Brazil. This work aims to describe the clinical characteristics of Brazilian children with food allergy, diagnosed through the Double-Blind Placebo-Controlled Food Challenge (DBPCFC). Methods: Of the evaluated patients, 234 children with clinical suspicion of food allergy and positive food allergy test between 1993 and 2005 were selected prospectively in a Pediatric Allergy and Pneumology Clinic. In order to confirm the diagnosis of food allergy, the DBPCFC was used with suspected allergenic food. Results: Of the 234 TPDCPCs performed, 30 tests were positive (12.8%), more frequently in children less than two years old and male sex. Of these positive tests, 26 (86.6%) were positive for eggs or cow's milk. Patients with initial diagnosis of atopic dermatitis or gastrointestinal allergy had a positive TPDCPC more frequently than patients with respiratory symptoms. Among the symptoms presented during the TPDCPC, cutaneous (60%) and respiratory symptoms (56.67%) prevailed. Conclusion: The incidence of food allergy in the clinically suspected population was 12.8%. Cow's milk and eggs are the main foods responsible for food allergy in our setting, and they are more common in children less than two years old. A positive allergic test is a poor predictor of food allergy (PPV = 13.5%), but a negative allergic test virtually eliminates this diagnosis, as its negative predictive value in the studied population was close to 100%.
Assuntos
Humanos , Recém-Nascido , Lactente , Pré-Escolar , Criança , Testes Cutâneos , Hipersensibilidade Alimentar , Pacientes , Sinais e Sintomas , Incidência , Prevalência , Valor Preditivo dos Testes , Hipersensibilidade a Leite , Hipersensibilidade a Ovo , Hipersensibilidade a Amendoim , Dermatite Atópica , AlimentosRESUMO
INTRODUCTION: The prevalence of peanut allergy (PA) has increased, affecting approximately 1.1% of children in Western countries. PA causes life-threatening anaphylaxis and frequently persists for life. There are no standardized curative therapies for PA, and avoidance of peanuts remains the main therapeutic option. A better understanding of the pathogenesis of PA is essential to identify new treatment strategies. Intestinal dendritic cells (DCs) are essential in the induction and maintenance of food tolerance because they present dietary allergens to T cells, thereby directing subsequent immune responses. Areas covered: In this review, we discuss the factors related to the acquisition of oral tolerance to peanut proteins. We focus on intestinal DC-related aspects, including the latest advances in the biology of intestinal DC subtypes, effect of tolerance-inducing factors on DCs, effect of dietary components on oral tolerance, and role of DCs in peanut sensitization. Expert commentary: Given the increasing prevalence of PA, difficulty of avoiding peanut products, and the potentially serious accidental reactions, the development of novel therapies for PA is needed. The ability of DCs to trigger tolerance or immunity makes them an interesting target for new treatment strategies against PA.
Assuntos
Alérgenos/imunologia , Apresentação de Antígeno , Células Dendríticas/imunologia , Mucosa Intestinal/imunologia , Hipersensibilidade a Amendoim/imunologia , Linfócitos T/imunologia , Criança , Pré-Escolar , Células Dendríticas/patologia , Feminino , Humanos , Mucosa Intestinal/patologia , Masculino , Hipersensibilidade a Amendoim/epidemiologia , Hipersensibilidade a Amendoim/patologia , Prevalência , Linfócitos T/patologiaRESUMO
OBJECTIVE: To confirm new observations on peanut allergy and answer current concerns that families and healthcare providers have about peanut allergy. STUDY DESIGN: Children who presented with a story of peanut allergy or peanut sensitization were asked to participate in a registry, which allowed an analysis focused on questions that a food allergy support group had about children with peanut allergy or sensitization. RESULTS: A total of 1070 children were entered into the registry over 5 years. Two-thirds had a reaction to peanut. Children with peanut allergy were predominantly male (63%), white (78%), and with private health insurance (80%). Most reactions involved the skin (55%) and anaphylaxis occurred in 35%. The median age of a reaction was 1 year old. Atopic dermatitis was noted in 60% and asthma in 41%. Additional food allergy was noted in 58%. When second exposures occurred 28% had a more severe reaction. Skin test size did not differentiate the type of a reaction and children with anaphylaxis had slightly higher specific IgE levels. Severe reactions with inadvertent exposure in children who were peanut sensitized was rare (<1%). CONCLUSIONS: The strategies for peanut allergy prevention and treatment have evolved. The data obtained in this large registry can answer many questions that families and healthcare providers have during this transition.
Assuntos
Hipersensibilidade a Amendoim/epidemiologia , Adolescente , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Indiana/epidemiologia , Lactente , Masculino , Hipersensibilidade a Amendoim/complicações , Hipersensibilidade a Amendoim/diagnóstico , Hipersensibilidade a Amendoim/terapia , Sistema de Registros , Fatores de RiscoRESUMO
BACKGROUND: In our country, the prevalence and the factors associated to peanut allergy are unknown, a health problem that has been emerging worldwide. OBJECTIVE: To establish the prevalence and the factors that are associated to peanut allergy amongst school children. METHODS: This is a population-based cross-sectional study. We included 756 children aged 6-7 years. The children's parents were questioned about their peanut intake habits. A structured questionnaire was applied, it included questions regarding peanut intake; family and personal history of asthma; rhinitis; and atopic dermatitis. Allergic reactions to peanuts were registered as: probable, convincing and systematic. The statistical analyses included logistical regression models to look for associated factors. RESULTS: Males were 356/756 (47.1%). Peanut allergy prevalence: probable reaction: 14/756 (1.8%), convincing reaction: 8/756 (1.1%) and systemic reaction: 3/756 (0.4%). Through multivariate analysis, the presence of symptoms of allergic rhinitis (OR=4.2 95% CI 1.3-13.2) and atopic dermatitis (OR=5.2; 95% CI 1.4-19.5) during the previous year, showed significant association to probable peanut reaction. The former year, the presence of atopic dermatitis was the only variable that was substantially associated to a convincing reaction (OR=7.5; 95% CI 1.4-38.4) and to a systematic reaction (OR=45.1; 95% CI 4.0-510.0), respectively. CONCLUSIONS: The reported prevalence of peanut allergy was consistent with that found in previous studies; symptoms of allergic rhinitis and atopic dermatitis were identified as associated factors to peanut allergy.