Taraneh Dean

Peanut allergy in relation to heredity, maternal diet, and other atopic diseases: results of a questionnaire survey, skin prick testing, and food challenges.

Abstract Objectives: To determine rates of other atopic manifestations in people with peanut allergy and the prevalence of such allergy in their families. Design: A survey of people with self reported peanut allergy and people referred by their general practitioner for suspected peanut allergy; survey and skin testing of 50 children with reported peanut allergy and their available first degree relatives. Subjects: 622 adults and children with reported, suspected, or known peanut allergy. Main outcome measures: Prevalence of peanut allergy and other allergies in the families of people with peanut allergy. Results: 622 valid completed questionnaires were returned out of the 833 questionnaires dispatched (74.7%). All forms of atopy were both more common in successive generations (P<0.0001) and more common in maternal than paternal relatives (P<0.0001). Peanut allergy was reported by 0.1% (3/2409) of grandparents, 0.6% (7/1213) of aunts and uncles, 1.6% (19/1218) of parents, and 6.9% (42/610) of siblings. Consumption of peanuts while pregnant or breast feeding was more common among mothers of probands aged </=5 years than mothers of probands aged >5 years (P<0.001). Age of onset correlated inversely with year of birth (r = -0.6, P<0.001). Skin prick testing of 50 children with reported peanut allergy and their families: 7 probands (14%) had a negative result for peanut. Peanut allergy was refuted by food challenge in all those tested (5/7). No parent and 13% (5/39) of siblings had a positive result on skin prick testing for peanut. Two of these siblings had negative challenge with peanuts. The prevalence of peanut allergy in siblings is therefore 3/39 (7%). Conclusions: Peanut allergy is more common in siblings of people with peanut allergy than in the parents or the general population. Its apparently increasing prevalence may reflect a general increase of atopy, which is inherited more commonly from the mother. Peanut allergy is presenting earlier in life, possibly reflecting increased consumption of peanut by pregnant and nursing mothers. Key messages The apparent epidemic of peanut allergy is a reflection of the general increase in atopic diseases and increased case identification The age of onset of peanut allergy is decreasing, possibly secondary to increased consumption by mothers and by infants early in life Peanut allergy affects 7% of siblings of people with peanut allergy but only 1.3% of the general population

Clinical characteristics of peanut allergy

Background Current clinical advice regarding peanut allergy is based on small series of patients.

Prevalence and cumulative incidence of food hypersensitivity in the first 3 years of life

Background:  Prevalence and incidence of food hypersensitivity (FHS) and its trends in early childhood are unclear.

Interleukin-8 concentrations are elevated in bronchoalveolar lavage, sputum, and sera of children with cystic fibrosis.

ABSTRACT: Concurrent pulmonary inflammation and neutrophil infiltration are characteristic of children with cystic fibrosis (CF). The production of the major neutrophil chemotactic cytokine IL-8 by alveolar macrophages or other cells could be of great importance in the pathology of acute lung disease, but its role in the persistent lung inflammation characteristic of CF has not been evaluated. In this study, we have measured, by ELISA, the concentration of IL-8 in sputum, bronchoalveolar lavage, and sera specimens obtained from children with CF. For comparison, IL-8 in bronchoalveolar lavage obtained from asthmatic patients and from non-CF children with or without lung infection and in sera from age-matched controls was measured. High levels of IL-8 were measured in sputum (mean = 2952 pM) and in bronchoalveolar lavage (mean = 6624 pM) from CF patients. In both cases, there was a significant correlation between clinical status (Schwach-man score) and IL-8 levels. This was not true for IL-8 levels measured in sera, which nevertheless were significantly higher in CF patients (p = 0.0001) than in normal controls in the over-10-y age group.

Time trends in the prevalence of peanut allergy: three cohorts of children from the same geographical location in the UK

Background:  This article investigated the prevalence of peanut allergy in three cohorts of children born in the same geographical location, Isle of Wight, UK and seeks to determine whether the prevalence of peanut allergy has changed between 1994 and 2004.

Prevalence of sensitization reported and objectively assessed food hypersensitivity amongst six‐year‐old children: A population‐based study

There is a paucity of information on food hypersensitivity (FHS) in young children and there are even fewer population‐based studies in this area. The aim of the study was to determine the prevalence of parentally reported FHS, and objectively diagnosed FHS amongst six‐year‐old children and to establish the rates of sensitization to key allergens. This population‐based cohort study recruited 798 6‐year‐olds resident on the Isle of Wight (UK). Sensitization rates, reported rates of FHS and objectively assessed FHS was established using food challenges. A total of 94 (11.8%) 6 yr olds reported a problem with a food or food ingredient. The rate of sensitization to the pre‐defined panel of food allergens was 25/700 (3.6%). Based on open food challenge and/or suggestive history and skin tests, the prevalence of FHS was 2.5% (95% CI 1.5–3.8). Based on double‐blind challenges, a clinical diagnosis or suggestive history and positive skin tests, the prevalence was 1.6% (95% CI 0.9–2.7). The rates of perception of FHS are higher than the prevalence of sensitization to main food allergens and the prevalence of FHS based on food challenges. Milk, peanut and wheat were the key food allergens amongst those with positive challenges.

HLA class II DRB1, DQB1 and DPB1 genotypic associations with peanut allergy : evidence from a family-based and case-control study

Peanut is one of the most common foods provoking allergic reactions and is the most frequent cause of fatal and near‐fatal food‐induced anaphylaxis. However, as yet, little is known of the genetic and immunological mechanisms which underly peanut allergy.

Serological characteristics of peanut allergy

Peanut is the most common cause of severe or fatal food‐associated anaphylaxis. Studies indicate that peanut extracts contain many allergenic proteins. The identification of major and minor allergenic components is necessary for standardization of experimental and diagnostic extracts.

Role of elevated plasma soluble ICAM-1 and bronchial lavage fluid IL-8 levels as markers of chronic lung disease in premature infants.

BACKGROUND--Pulmonary neutrophilia characterises both the relatively transient inflammation associated with infant respiratory distress syndrome (IRDS) and the persistent inflammation of chronic lung disease. The possibility that persistently raised markers of inflammation indicate the development of chronic lung disease in low birth weight (< 1730 g) preterm (< 31 weeks) infants was therefore investigated. METHODS--Soluble ICAM-1 (sICAM-1) levels in plasma, and interleukin (IL)-8 and myeloperoxidase (MPO) levels in bronchial lavage fluid (BLF) obtained from 17 infants on days 1, 5, and 14 following birth were measured and correlations with the number of neutrophils in BLF sought. Peripheral neutrophils were isolated on Polymorphoprep and chemotactic responsiveness to IL-8 was assessed using micro Boyden chambers. RESULTS--Sixteen infants developed IRDS and, of these, 10 infants subsequently developed chronic lung disease. Levels of IL-8 in BLF at 14 days of age correlated with the long term requirement for intermittent positive pressure ventilation (IPPV). Interleukin 8 levels in BLF correlated with neutrophil numbers and MPO concentration, suggesting both recruitment and activation in response to this cytokine. Antibody depletion studies showed that approximately 50% of total neutrophil chemotactic activity in BLF was due to IL-8. No difference in peripheral neutrophil chemotactic responsiveness at any age was observed for infants with IRDS or chronic lung disease. Plasma soluble intercellular adhesion molecule (sICAM-1) was higher at 14 days of age in infants who developed chronic lung disease than in those with resolving IRDS, and correlated with severity of disease, as indicated by duration of IPPV. CONCLUSIONS--The results indicate that high levels of plasma sICAM-1 and IL-8 in BLF at day 14 correlate with the development of chronic lung disease and indicate the severity of disease.

Prevention of sensitization to house dust mite by allergen avoidance in school age children: a randomized controlled study

Background Sensitization to dust mites predisposes to asthma and allergic rhinitis, and prevention of this sensitization might reduce the rising prevalence of these disorders.