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AIM: We investigated phenotypes of milk hypersensitivity among schoolchildren aged 11-12 in Northern Sweden.

METHODS: In a population-based cohort, 1,824 (98%) children aged 11-12 participated in a questionnaire survey, skin prick testing, interviews on food hypersensitivity and assessment of body mass index (BMI). Of the 265 children reporting milk hypersensitivity, milk avoidance and no celiac disease, 236 (89%) participated in a structured interview and blood samples for analyses of milk-specific Immunoglobulin E. The children were then categorised into milk hypersensitivity phenotypes according to preset criteria.

RESULTS: In all, 14.5% reported milk hypersensitivity. Of these, 3% were categorised as current milk allergy, 23% as outgrown milk allergy, 40% as probable lactose intolerance and 11% were non-definable. Furthermore, 23% had discontinued their elimination diet. Milk allergy was associated with other atopic disorders and lower BMI, with an odds Ratio of 0.82 and 95% confidence interval of 0.80-0.98. Only 2% had previously undergone an oral challenge.

CONCLUSION: The most common symptom phenotypes among Swedish children aged 11-12 with self-reported milk hypersensitivity and milk avoidance, were lactose intolerance and outgrown milk allergy while current milk allergy was uncommon. Children with milk allergy had a lower BMI and most lacked a challenge proven diagnosis. 

Objectives Knowledge about the prevalence of allergies to foods in childhood and adolescence is incomplete. The purpose of this study was to investigate the prevalence of allergies to milk, egg, cod, and wheat using reported data, clinical examinations, and double-blind placebo-controlled food challenges, and to describe the phenotypes of reported food hypersensitivity in a cohort of Swedish schoolchildren. Methods In a population-based cohort of 12-year-old children, the parents of 2612 (96% of invited) completed a questionnaire. Specific IgE antibodies to foods were analyzed in a random sample (n=695). Children reporting complete avoidance of milk, egg, cod, or wheat due to perceived hypersensitivity and without physician-diagnosed celiac disease were invited to undergo clinical examination that included specific IgE testing, a celiac screening test, and categorization into phenotypes of food hypersensitivity according to preset criteria. Children with possible food allergy were further evaluated with double-blind challenges. Results In this cohort, the prevalence of reported food allergy to milk, egg, cod, or wheat was 4.8%. Food allergy was diagnosed in 1.4% of the children after clinical evaluation and in 0.6% following double-blind placebo-controlled food challenge. After clinical examination, children who completely avoided one or more essential foods due to perceived food hypersensitivity were categorized with the following phenotypes: allergy (29%), outgrown allergy (19%), lactose intolerance (40%), and unclear (12%). Conclusions There was a high discrepancy in the prevalence of allergy to milk, egg, cod and wheat as assessed by reported data, clinical evaluation, and double-blind food challenges. Food hypersensitivity phenotyping according to preset criteria was helpful for identifying children with food allergy.

Double-blind placebo-controlled food challenges are considered the most reliable method to diagnose or rule out food allergy. Despite this, there are few validated challenge recipes available. The present study aimed to validate new recipes for low-dose double-blind placebo-controlled food challenges in school children, by investigating whether there were any sensory differences between the active materials containing cow's milk, hen's egg, soy, wheat or cod, and the placebo materials. The challenge materials contained the same hypoallergenic amino acidbased product, with or without added food allergens. The test panels consisted of 275 school children, aged 810 and 1415yr, respectively, from five Swedish schools. Each participant tested at least one recipe. Standardized blinded triangle tests were performed to investigate whether any sensory differences could be detected between the active and placebo materials. In our final recipes, no significant differences could be detected between the active and placebo materials for any challenge food (p>0.05). These results remained after stratification for age and gender. The taste of challenge materials was acceptable, and no unfavourable side effects related to test materials were observed. In summary, these new validated recipes for low-dose double-blinded food challenges contain common allergenic foods in childhood; cow's milk, hen's egg, soy, wheat and cod. All test materials contain the same liquid vehicle, which facilitates preparation and dosing. Our validated recipes increase the range of available recipes, and as they are easily prepared and dosed, they may facilitate the use of double-blind placebo-controlled food challenges in daily clinical practice.

Aim At the extremes of latitude, UVB intensity is insufficient for adequate vitamin D synthesis in winter. Fatty fish, vitamin D enriched milk, margarine and eggs are main dietary sources of vitamin D. Their elimination may increase the risk of vitamin D deficiency. The aim was to assess vitamin D status in food-allergic adolescents eliminating milk, egg and/or fish compared with adolescents on normal diets. Methods In winter, vitamin D intake was assessed by a food frequency questionnaire in 20 food-allergic adolescents and 42 controls in the population-based Obstructive Lung Disease In Northern Sweden (OLIN) cohort studies. Vitamin D supplementation was queried. Serum 25-hydroxyvitamin D [S-25(OH)D] and S-parathormone (S-PTH) levels were determined. Results Mean (SD) dietary vitamin D intake was 7.9 (3.6) g/day in allergic adolescents and 7.8 (3.4) in controls (p>0.05). Mean (SD) S-25(OH)D levels in supplement consumers were 44 (18) nmol/L compared with 35 (10) in non-consumers (p=0.03). S-25(OH)D and S-PTH levels were similar in food-allergic adolescents and controls (p>0.05). Eighty-two percentage had deficient S-25(OH)D levels <50nmol/L, and none reached levels >75nmol/L. Conclusion Vitamin D deficiency was as common in food-allergic adolescents as in controls although the vitamin D intake met national recommendations. Large-scale studies on the prevalence of vitamin D deficiency in this region are needed.

Nutritional studies in patients with chronic obstructive pulmonary disease (COPD) are often based on oral nutritional supplementation and are of short duration. Our aim was to study the changes in body weight and physical performance in COPD patients after receiving the dietary advice for 1 year. Thirty-six patients with COPD as a primary diagnosis (mean age: 68.5+/-7.8 years), referred to a pulmonary rehabilitation program were studied. Each patient received dietary advice individually. Body weight had increased significantly by 1.3kg (p=0.02) and walking distance by 83.2m (p=0.007) after 1 year. There was an increase in mean handgrip strength after 1 year (1.6kg, p=0.07). The mean intake of energy and protein expressed as percent of energy and protein requirement had increased after 1 year (15%, p<0.001, and 5.6%, p=0.09, respectively). Handgrip strength correlated significantly with energy (r=0.53, p=0.002), fat (r=0.50, p=0.02) and protein intake (r=0.41, p=0.002) after 1 year. In conclusion, positive effects on body weight, handgrip strength and walking distance in patients with COPD were seen after receiving dietary advice with a 1-year follow-up.