Vitamin D deficiency in children and adolescents with food allergy: Association with number of allergens, sun exposure and nutritional status

Our objective was to describe the serum vitamin D concentrations of children and adolescents with food allergy (FA) and to verify the association between the number of food allergens involved, length of sun exposure, and nutritional status. Through a cross-sectional study, 79 patients with FA, from ages 2 to 15 years, were assessed and followed up in a reference outpatient clinic, in Sao Paulo, Brazil. Clinical and biochemical data were collected for analysis of 25(OH)D, calcium, phosphorus, phosphatase, parathyroid hormone (PTH), and high-sensitivity C-reactive protein (hs-CRP). The cut-off point used for vitamin D deficiency was 25(OH)D ≤ 20 ng/mL. Vitamin D deficiency was detected in 45.6% of patients with a median age of 6.9 years (Interquartile range [IQR] 4.7; 10.2). The median serum 25(OH)D concentration was 21.1 ng/mL (IQR 17.8; 26.0). Multivariate linear regression was performed considering serum vitamin D level as a dependent variable. Allergy to multiple foods (inverse) and length of sun exposure (direct), but not nutritional status, were independently associated with serum 25(OH)D levels (P = 0.034 and P = 0.014, respectively). Patients with cow’s milk allergy also showed lower vitamin D concentrations in comparison with other FA (19.1 ng/mL [IQR 16.6; 24.4] vs 22.2 ng/mL [IQR 18.1; 27.1] [P = 0.056]). Vitamin D deficiency affected about half of individuals with FA. Multiple food allergy was associated with lower vitamin D concentrations, reinforcing the importance of monitoring vitamin D status in patients with FA (AU)

Open oral food challenge in the confirmation of cow's milk allergy mediated by immunoglobulin E

Background The most reliable method to diagnose food allergy or to determine tolerance is the oral food challenge. Objectives The aim of this study was to describe the open oral food challenge applied to children with suspicion of cow's milk allergy mediated by immunoglobulin E, and evaluate the relation between the clinical history and skin prick test with the challenge outcomes. Patients and methods Forty-six children (median age 13.8 months), with clinical history of immediate reactions to cow's milk and positive skin prick test, underwent an open oral food challenge with cow's milk. Results The challenge was positive in 41.3%. Cutaneous reactions were the most common (73.7%), followed by respiratory (57.9%) and gastrointestinal reactions (36.8%). According to the severity of the reactions, 57.9%, 36.8% and 5.3% had mild, moderate and severe reactions, respectively. Oral antihistamine was sufficient as treatment in all positive cases. A higher frequency of positive skin prick test with total milk and casein was observed in children with positive oral food challenge. There was a significant agreement between the reactions reported by the family history and those observed during the challenge for 68.4% of children with positive results (Kappa=0.728; p<0.001). Conclusions The method was considered suitable for children up to three years of age, and is safe and easy to perform. There was a significant correlation between the clinical history and the challenge outcomes. A positive skin prick test with total milk and casein was significantly associated with positive challenge results(AU)