M.Martin Esteban

Frequency of food allergy in a pediatric population from Spain

We evaluated the prevalence and characteristics of the principal foods implicated in 355 children diagnosed with IgE‐mediated food allergy. Diagnosis was established on the basis of positive clinical history for the offending food, positive specific IgE by skin prick test and RAST, and open food challenge. Our results showed the principal foods involved in allergic reactions are: eggs, fish, and cows milk. These are followed in frequency by fruits (peaches, hazelnuts and walnuts), legumes (lentils, peanuts and chick peas) and other vegetables (mainly sunflower seeds). The legumes demonstrated the highest degree of clinical cross‐reactivity. Most patients with food allergy reacted to one or two foods (86.7%). Only 13.3% of patients reacted to 3 or more foods, mostly to legumes and fruits. We found that food allergy begins most frequently in the first (48.8%) and second (20.4%) years of life. Allergy to proteins of cows milk, egg, and fish begins predominantly before the second year, demonstrating a clear relationship with the introduction of these foods into the childs diet. Allergy to foods of vegetable origin (fruits, legumes and other vegetables) begins predominantly after the second year.;

Fish allergy: Evaluation of the importance of cross-reactivity

Fish constitute one of the most important groups of allergens in the induction of immediate (type I) food hypersensitivity. In our environment, fish allergy is present in 22% of all patients with a diagnosis of food hypersensitivity. We studied the allergenic significance of the fish species considered most representative because of their greater consumption in our environment (flatfishes: Pleuronectiformes such as sole, whiff, and witch; Gadiformes such as hake; and Scombriformes such as albacore) or because of the results of previous studies of Gadiformes such as cod. Through the use of isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting, we have observed that several allergens common to all these species are able to bind specific IgE from the sera of sensitized patients. This allergenic community has been confirmed by radioallergosorbent inhibition. Another group of species-specific allergens focuses in the regions at about pH 5 and with molecular weights less than 14 kilodaltons; these allergens correspond to sarcoplasmic parvoalbumins. From the results observed, which have been confirmed by various procedures and techniques, we conclude that hake is the fish with the capability to induce the strongest IgE response, followed by whiff; the witch seems to be the least allergenic of all flatfishes. Among all species studied, albacore was the least allergenic. These results may be considered when one introduces supplementary feeding with fish in infants, most particularly in infants at high risk for atopy.

Allergy to white potato

Allergy to potato is uncommon, and even more uncommon is allergy to potato pollen. The occurrence of both phenomena in the same patient made it possible to study cross-reactivity patterns of potato antigens. An 11-year-old girl, exclusively breast-fed for her first 4 months, developed anaphylactic symptoms after ingestion of potato at 5 months of age when she was fed potato for the first time. Subsequently, she developed urticaria, angioedema, and respiratory and systemic symptoms on contact with potatoes, ingestion of potatoes, and exposure to cooking potatoes or potato pollen. Three allergenic extracts from potato pulp, peel, and pollen were prepared. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and isoelectrofocusing of the three extracts were performed. IgE-mediated allergy to these extracts was demonstrated by means of immediate skin test reactivity, positive passive transfer, RAST, RAST inhibition, and leukocyte histamine release. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the pulp extract followed by electroblotting and autoradiography demonstrated specific IgE antibodies directed against several proteins ranging from 14,000 to 40,000 daltons.

Incidencia de alergia a proteínas de leche de vaca en el primer año de vida y su repercusión en el consumo de hidrolizados

objetivo Calculo de la incidencia de alergia a proteinas de lechede vaca (APLV) en el lactante y coste del tratamiento con hidrolizados de leche de vaca en la comunidad de Madrid Pacientes y metodos Lactantes con sospecha de APLV nacidos entre el 1 demarzo de 2000 y el 28 de febrero de 2001 en el Hospital LaPaz pertenecientes a las areas que atiende el Hospital Infantil.Se les aplico el algoritmo diagnostico de APLV delservicio. Se realizo el calculo teorico del consumo de hidrolizadosutilizados en el tratamiento de los APLV y seextrapolo a la comunidad de Madrid Resultados Nacidos vivos en el Hospital La Paz pertenecientes a lasareas citadas: 5.356 ninos. Consultaron por sospecha fundadade APLV: 185 ninos. Se diagnosticaron como alergicosa PLV a 101 (54 %). La incidencia calculada de APLV fue de:101/5.356: 1,9 %. Nacidos en la comunidad de Madrid enel mismo periodo: 57.078 ninos. El numero de posiblesAPLV en un ano seria de 1.084. El calculo aproximado deconsumo de hidrolizados en el primer ano de vida pornino, supone un coste de 1.585,72 3. El gasto de hidrolizadosen los 1.084 alergicos en la comunidad de Madrid seriade 1.718.922,9 3. El gasto de los 923 ninos en los que sedescarto alergia supondria 1.463.621,8 3 Conclusiones La incidencia de APLV en el primer ano de vida en nuestromedio es de, al menos, 1,9 %. El diagnostico correctopermite descartar APLV en casi la mitad de los casos, evitandosometer al lactante a dietas innecesarias y que suponenun elevado coste

La importancia alergénica de las legumbres

Resumen Las leguminosas son una fuente barata de proteinas que se cultivan practicamente en todo el mundo y son base de alimentacion en muchos paises en vias de desarrollo. En el area mediterranea y oriente medio se consumen principalmente lenteja y garbanzo. En cambio en paises anglosajones y sureste asiatico se consumen, de forma preferente, cacahuete y soja, respectivamente Las manifestaciones clinicas de la alergia a legumbres son similares para todas ellas y abarcan desde sindrome de alergia oral, urticaria, angioedema, rinitis, crisis asmaticas hasta anafilaxia e incluso muerte. Las legumbres tienen un alto grado de reactividad cruzada inmunologica; diversos autores han descrito reactividad cruzada entre diferentes legumbres y entre estas y varios alimentos vegetales. La alergenicidad de las legumbres se relaciona principalmente con alergenos procedentes de las proteinas de almacenamiento de las semillas, las vicilinas podrian ser un alergeno comun importante en la alergia clinica a legumbres, las profilinas se consideran causa de reactividad cruzada entre frutas, verduras y algunos polenes y son consideradas un panalergeno. Otros panalergenos de importancia creciente son las proteinas de transferencia lipidica Hay escasos estudios que valoren la evolucion a largo plazo de la alergia a legumbres. Se estan investigando nuevos agentes terapeuticos para el tratamiento de la alergia a cacahuete que podria ser extensible a otras legumbres

Exercise-induced asthma in asthmatic children. Predisposing factors

BACKGROUND Exercise-induced bronchoconstriction (EIB) has a high prevalence in children with asthma, and this is a common problem, even in case of controlled asthma, because of the high levels of physical activity in the childhood. OBJECTIVES The aim of our study was to identify factors associated with the development of EIB in children with controlled asthma. METHODS We studied children evaluated for asthma. A personal and familiar history was collected from each patient to estimate asthma severity, precipitating factors, exercise ability, immunotherapy treatment and atopic familiar disorders. Skin prick tests for inhalant allergens, pulmonary function tests (PFTs) and exercise challenge test (ECT) measurements were realized in every patient. We used the Chi Squared test to compare qualitative variables, the Students-t test for quantitative variables and a logistic regression analysis to estimate the independent effect of the variables. RESULTS We evaluated 132 asthmatic patients. Eighty-two, 6 to 14 years old (average 110 +/- 36.9 months), were included in the study. Forty one have coughing or wheezing with exercise at least three months ago, in addition to a positive ECT; 9 of these children had solitary EIB (group A), and 32 (group B) had controlled chronic asthma, 27 intermittent and 5 moderately persistent. Forty one controlled asthmatic children, 39 intermittent, 1 mildly persistent and 1 moderately persistent (group C) had a good tolerance for exercise with a negative ECT. No differences were found in familiar history, asthma severity or evolution time in B vs C group. We found that 35 patients (42,68 %) patients were sensitized to indoor allergens: 24 (58,53 %) were patients suffering EIB and 11 (26,8 %) allowed to group C. Precipitating factors of asthma were in group B: respiratory infections in 19 cases, pollen in 20 and in 10 indoor allergens exposure. In group C: 14 patients had asthmatic symptoms with viral respiratory infections, 32 with pollen and 2 with indoor allergens exposure. A patient from group A had allergy rhinitis after exposure to cats. Allergy to indoor allergens demonstrated an direct association to EIB suffering (p = 0,026). Twenty six patients with allergic asthma followed pollen immunotherapy treatment, 7 of group B (33,3 %) and 19 (59,3 %) of group C. This treatment was inversely associated with EIB suffering (p = 0,048). A logistic regression analysis confirmed the independence of both variables as predisposing and protecting factors in EIB suffering. CONCLUSIONS Allergy to indoor allergens might be considered a risk factor for EIB. Immunotherapy treatment could be a protective factor against the development of EIB in children with allergic asthma.