Dietary assessment in children adhering to a food allergen avoidance diet for allergy prevention

OBJECTIVE: The purpose of this investigation was to verify if avoidance of allergenic foods in children adhering to a food allergen avoidance diet from birth was complete and feasible, and whether dietary assessment can be used as a tool in predicting the outcome of double-blind, placebo-controlled food challenges (DBPCFCs). DESIGN: Children adhering to an allergen avoidance diet from birth underwent DBPCFCs. The investigator-dietician verified whether the elimination was complete, using food frequency questionnaires for common allergenic foods. SETTING: University Medical Centre Groningen, the Netherlands. SUBJECTS: Thiry-eight children aged 1-13 years, who were consecutively referred to the University Medical Centre Groningen for DBPCFC between January 2002 and February 2004. RESULTS: Among the 38 children undergoing DBPCFCs, there were 15 challenges with egg, 15 with peanut, five with hazelnut and three with soy. Fifteen food challenges (39%) were positive. Small quantities of allergenic foods were inadvertently present in the diets of 13 patients (34%), were possibly present in the diets of 14 patients (37%) and could not be identified in the diets of 11 patients (29%). Seven patients (54%) who had inadvertently ingested small quantities of allergenic foods without sequelae had a positive DBPCFC. CONCLUSION: Dietary avoidance was incomplete and not feasible in most cases. Tolerance of small amounts of allergenic foods does not preclude positive challenge reactions. Dietary assessment does not seem a useful tool in predicting the outcome of DBPCFC in children adhering to an elimination diet. SPONSORSHIP: The Stichting Astma Bestrijding (Foundation for the Prevention of Asthma), The Netherlands.     

Dietary approaches to the prevention of food allergy

PURPOSE OF REVIEW: The primary prevention of food allergy and atopy has become a public health priority in developed countries. Although some preventive dietary interventions have entered common practice, the level of evidence underpinning these strategies varies. RECENT FINDINGS: Exclusive breast-feeding and delayed introduction of complementary foods from the age of 4-6 months are key strategies in primary food allergy and atopy prevention. Maternal elimination diets during pregnancy and lactation are currently not recommended. Partially and extensively hydrolyzed formulae may confer a small preventive effect in high-risk infants. Amino acid-based formula is, however, considered a treatment formula and not recommended for primary allergy prevention. The effect of prebiotic oligosaccharides and probiotic bacteria in prevention of food allergy remains unclear and requires further investigation. Maternal fish oil supplementation during pregnancy shows promise in reducing the risk of allergic sensitization in the infant, but prospective long-term data are required. Fish oil supplementation in young infants was not effective. SUMMARY: Although there is evidence for the primary dietary prevention of eczema and possible respiratory allergies, data on food allergy prevention have, so far, remained less convincing. Further prospective research is needed to clarify the effectiveness of dietary interventions in primary food allergy prevention.     

维生素D与儿童食物过敏的研究进展

近年来,食物过敏的发生率呈逐年上升趋势,婴幼儿为其高发人群,故应引起家长和儿科医生的广泛重视。目前,食物过敏的病因及其发病机制尚不明确,但最新研究发现,维生素D(VitD)与儿童食物过敏存在密切相关性,因其可影响人体免疫系统的调节作用。但目前国内外关于VitD与儿童食物过敏的相关资料研究较少,本文就VitD与食物过敏的流行病学及发病机制的最新研究进展作一综述。     

无锡地区儿童食物过敏情况分析

目的了解无锡市3～14岁儿童食物过敏的发生率及临床和实验室检查特点。方法采用抽样调查的方式,2016年1月至2017年12月在无锡市各区对3 858名3～14岁儿童进行食物过敏问卷调查,获取食物过敏发生率及临床特征。比较分析无锡食物过敏患儿的病史、实验室检查诊断特点。结果无锡地区3～14岁儿童食物过敏自我报告率6.53%。调查在常见食物过敏原中自我报告率以鱼虾最高,其值是2.85%;而过敏原SIgE检测阳性率以牛奶及奶制品最高,其值是1.61%。在我们调查共发现常见过敏原食物自我报告和相应的SIgE值X²检验比较差异均具有统计学意义(X²值分别是牛奶和奶制品452.7767、鸡蛋701.1511、鱼虾331.9857、花生390.5119、坚果497.9674、小麦126.9695、豆类或豆制品152.7221、水果154.551、蔬菜191.5006,P均<0.05)。检测到食物SIgE阳性与自我报告相符率中最高的是水果和蔬菜,其值是50%。结论无锡地区儿童食物过敏自我报告率6.53%,本地区自我报告食物过敏物质以鱼虾多见,而食物过敏...     

Cholesterol precursors and plant sterols in children with food allergy

BACKGROUND: The data on lipid metabolism in allergic children is limited. OBJECTIVE: We investigated lipid and sterol metabolism in young children whose diets were restricted because of food allergy. DESIGN: Children in group A [n = 21; mean (+/- SD) age: 1.78 +/- 0.73 y] were allergic to fish, eggs, and either cow milk or cereals; those in group B (n = 31, aged 1.45 +/- 0.58 y) were allergic to fish, eggs, and both cow milk and cereals. Cholesterol precursor and plant sterol to cholesterol ratios (10(2) x micro mol/mmol cholesterol) and apolipoprotein E phenotype distributions were analyzed in 36 subjects. The control group for cholesterol precursor and plant sterol measurements consisted of 18 healthy age-matched children. RESULTS: The mean serum cholesterol concentration was 3.6 +/- 0.6 mmol/L, and HDL cholesterol was 1.03 +/- 0.3 mmol/L in group A. Corresponding values in group B were 3.4 +/- 0.7 and 1.09 +/- 0.2 mmol/L. The daily cholesterol intake was low: 61.3 +/- 36.0 mg in group A and 50.7 +/- 48.5 mg in group B. Cholesterol precursor plant sterol concentrations were significantly higher in allergic subjects than in control subjects. CONCLUSIONS: Allergic children with restricted diets have a low intake of cholesterol and relatively low serum cholesterol concentrations. Dietary intake of plant sterols was obviously increased because of supplementation with rapeseed oil, which is rich in plant sterols, leading to elevated plant sterol concentrations. Plant sterols may have inhibited cholesterol absorption, which in turn stimulated cholesterol synthesis in compensation, also explaining the increased precursor sterol ratios in serum in our subjects.     

多不饱和脂肪酸与儿童食物过敏

在过去的20年里,食物过敏在全球范围内变得越来越普遍,迫切需要有效的预防治疗方法,而多不饱和脂肪酸可以影响人体的免疫反应,尤其是n-3多不饱和脂肪酸,可以通过“抑制炎症”的作用防止免疫紊乱的发展。本篇综述从食物过敏的影响因素出发,探讨了多不饱和脂肪酸与儿童食物过敏之间的关系,总结了目前关于多不饱和脂肪酸与食物过敏之间的研究成果,旨在为儿童食物过敏的防治提供新思路。     

The optimal diagnostic workup for children with suspected food allergy

Food allergy is defined as an abnormal immunologic reaction to food proteins that causes an adverse clinical reaction. In addition to well-known acute allergic reactions and anaphylaxis triggered by immunoglobulin E antibody–mediated immune responses to food proteins, there is an increasing recognition of cell-mediated disorders such as eosinophilic esophagitis and food protein–induced enterocolitis syndrome. More than 90% of food allergies in childhood are caused by eight foods: cow’s milk, hen’s egg, soy, peanuts, tree nuts, wheat, fish, and shellfish. The diagnostic workup for a child with suspected food allergy includes a detailed medical history, physical examination, food allergy screening tests, and responses to an elimination diet and an oral food challenge. None of the screening tests, alone or in combination, can definitely diagnose or exclude a food allergy. Novel diagnostic methods including those that focus on immune responses to specific food proteins or epitopes of specific proteins are under active study. Unconventional diagnostic methods are increasingly used, but they lack scientific rationale, standardization, and reproducibility. In selected cases, such as eosinophilic esophageal gastroenteropathies or food protein–induced gastroesophageal reflux disease, invasive procedures are mandatory for an accurate diagnosis. Properly done, an oral food challenge is still the gold standard in the diagnostic workup. An incorrect diagnosis is likely to result in unnecessary dietary restrictions, which, if prolonged, may adversely affect the child’s nutritional status and growth.     

Food allergy knowledge,perception of food allergy labeling,and level of dietary practice: A comparison between children with and without food allergy experience

BACKGROUND/OBJECTIVESThe prevalence of food allergies in Korean children aged 6 to 12 years increased from 10.9% in 1995 to 12.6% in 2012 according to nationwide population studies. Treatment for food allergies is avoidance of allergenic-related foods and epinephrine auto-injector (EPI) for accidental allergic reactions. This study compared knowledge and perception of food allergy labeling and dietary practices of students.SUBJECTS/METHODSThe study was conducted with the fourth to sixth grade students from an elementary school in Yongin. A total of 437 response rate (95%) questionnaires were collected and statistically analyzed.RESULTSThe prevalence of food allergy among respondents was 19.7%, and the most common food allergy-related symptoms were urticaria, followed by itching, vomiting and nausea. Food allergens, other than 12 statutory food allergens, included cheese, cucumber, kiwi, melon, clam, green tea, walnut, grape, apricot and pineapple. Children with and without food allergy experience had a similar level of knowledge on food allergies. Children with food allergy experience thought that food allergy-related labeling on school menus was not clear or informative.CONCLUSIONTo understand food allergies and prevent allergic reactions to school foodservice among children, schools must provide more concrete and customized food allergy education.     

Incidence of food allergy and zinc deficiency in children treated for atopic dermatitis

Among the 134 children who were admitted to hospital with atopic dermatitis, authors found 41, suffering from food allergy and 39, being hypozincaemic; the latter ones belonged to the group of patients with serious and extended ekzemic laesions. The lymphoblast transformation with aspecific mitogen in the blood of ten hypozincaemic patients with negative tuberculinplaster-reaction in 9 cases showed pathological decreased level, and after one month of zinc intake, 8 children's lymphoblast transformation became normal.     

攀枝花市0~3岁儿童食物过敏流行病学调查

目的了解四川省攀枝花市0~3岁儿童食物过敏现状。方法2010年1月—2012年12月,采用分层随机抽样方法在市内3个城区随机抽取0~3岁儿童1 387名进行问卷调查、体检,对所有纳入儿童进行皮肤点刺试验（SPT）,根据SPT和病史结果确定可疑病例进行食物排除（FE）和食物激发试验,由激发试验结果确诊食物过敏;筛查的9种食物包括鸡蛋、牛奶、鱼、虾、橘子、核桃、大豆、花生和小麦。结果除28名失访外,共计1 359名儿童完成调查与体检,食物激发试验确诊食物过敏儿童103例,食物过敏检出率为7.58%,病史阳性率15.96%,SPT阳性率10.45%,FE阳性率9.49%;最常见的食物过敏原为鸡蛋（4.12%）,其次是牛奶（2.43%）,鱼（1.77%）,虾（0.74%）,花生、核桃、橙子等（各0.22%）;在过敏儿童中单种食物过敏者70.87%,2种食物过敏26.22%,>2种食物过敏2.91%;常见的食物激发临床表现主要为皮肤症状。结论攀枝花市0~3岁儿童食物过敏率为7.58%,最常见的食物过敏原为鸡蛋,其次是牛奶、鱼和虾,单一食物过敏最常见,食物激发临床表现以皮肤症状为主。     

Parental perception of food allergy or intolerance in children under 4 years of age

The perceived prevalence of food allergy among parents of pre-school children in Ireland is unknown. An interview-assisted questionnaire was used to interview the parents of 600 children, aged 0–4 years, about food allergy. Twelve and a half per cent of the children were perceived by their parents to be food allergic. However, no instance of food allergy in children aged under 6 months was reported. Hyperactivity was the most common symptom noted, with sweets, sugary drinks and food colours being the most frequently implicated foods. Rash, the second most common symptom cited was largely associated with dairy products and eggs. Neither parental age, education, socio-economic groups or infant feeding practices affected perception of food allergy. Food allergy was diagnosed primarily by the parents themselves using simple food avoidance.     

Living with food allergy

Food allergy is among the most common of the allergic disorders, with a prevalence of 6-8 per cent in children up to the age of three. However, many people self-diagnose, putting their children at risk of malnutrition, possibly as a result of lack of awareness by health professionals of food allergy as a potential cause of conditions such as infantile eczema, chronic diarrhoea, faltering growth and gastrooesophageal reflux. NICE (The National Institute for Health and Clinical Excellence) recently published guidelines, which they hope will help to improve the diagnosis of food allergies within the community. If food allergy or lactose intolerance is suspected, the mainstay of a diagnostic work up should comprise of a detailed allergy-focused clinical history, part of which will involve determining whether the adverse reaction is typically an immediate (IgE mediated) or more delayed-type (non-IgE mediated) allergic reaction, or whether it may be lactose intolerance; a form of non-allergic hypersensitivity.