Food allergy is an immunologically mediated adverse reaction to food protein. Cow's milk protein allergy (CMPA) is the most frequent type and is the one that is most difficult to diagnose. This study had the objective of analyzing the accuracy of hypersensitivity and specific IgE skin tests among children with CMPA and predominantly gastrointestinal clinical manifestations. The participants in this study were 192 children aged one and five (median of 2 yr). Among these, 122 underwent open oral challenge to the suspected food. After evaluating the sensitivity, specificity and positive and negative predictive values (respectively, PPV and NPV) of skin and specific IgE tests in relation to the gold standard (open oral challenge); all the children underwent the skin prick test (SPT), specific IgE test and atopy patch test (APT) for cow's milk, eggs, wheat and peanuts and the open oral challenge for the food to which the child was sensitive or had suspected sensitivity. Presence of food allergy was confirmed for 50 children (40.9%). Among these cases, 44/50 (88%) were of allergy to cow's milk protein. Children who presented a positive response to an oral challenge to cow's milk protein were considered to be cases, while the controls were children with negative response. Twenty-two of the 44 cases (50.0%) presented symptoms within the first 4 h after the challenge. The SPT presented 31.8% sensitivity, 90.3% specificity, 66.7% PPV and 68.4% NPV. The APT presented 25.0% sensitivity, 81.9% specificity, 45.8% PPV and 64.1% NPV. The specific IgE test presented, respectively, 20.5%, 88.9%, 52.9% and 64.6%. Despite the operational difficulty and the possible exposure risk, oral challenge is the best method for diagnosing CMPA, because of the low sensitivity and PPV of skin and specific IgE tests.

BACKGROUND:Bovine beta-casein is a cow's milk protein that targets both humoral and cellular immune responses in patients with Type 1 diabetes and, to a lesser degree, also in normal subjects. In this study we aimed to determine whether the avoidance of cow's milk consumption early in life could prevent the development of antibody response to bovine beta-casein despite the mother being exposed on a daily basis to cow's milk consumption.

MATERIALS AND METHODS:We measured the antibody response to bovine beta-casein using an ELISA method in 28 healthy infants under 4 months of age, of whom 16 were exclusively breast-fed and 12 were bottle-fed with cow's milk. In addition, beta-casein antibodies were measured in 37 prepubertal children with Type 1 diabetes and in 31 healthy children who were exposed to cow's milk or dairy products to see whether differences in antibody titers exist in this young age group. Antibodies binding to beta-casein were also evaluated by immunoblotting analysis.

RESULTS:Elevated levels of beta-casein antibodies were found in bottle-fed infants compared to breast-fed infants (p<0.0001). Antibody levels to bovine beta-casein were also significantly higher in children with Type 1 diabetes compared to age-matched controls (p=0.03). By western blot analysis we confirmed specific binding to bovine beta-casein in bottle-fed infants, in children with Type 1 diabetes and in controls exposed to cow's milk, but not in infants who were exclusively breast-fed.

CONCLUSIONS:The results of this study indicate that breastfeeding within the first 4 months of life prevents the generation of antibody response to bovine beta-casein despite the mothers' consumption of cow's milk during the breastfeeding period. These findings may have relevance for disease prevention.

OBJECTIVE: To determine whether chicken-based formula can replace soy-based formula in infants with cow milk allergy.

SUBJECTS AND METHODS: Thirty-eight infants with cow's milk allergy, aged between 2-24 months of age were randomized to receive either chicken-based formula or soy-based formula for 14 days.

RESULTS: In the group of soy-based formula, 12 out of 18 infants had evidence of intolerance and could not continue with the formula. However, only 4 out of 20 infants in the chicken-based formula group had evidence of clinical intolerance. All other 16 infants were fed the chicken-based formula with success. The number of infants who were intolerant to chicken formula was significantly lower than the number of those fed soy-based formula (p = 0.009).

CONCLUSION: Chicken-based formula can be used more effectively than soy-based formula in infants with cow milk allergy.

OBJECTIVE:To study the prevalence of atopic dermatitis in exclusively breast-fed infants of allergic mothers who were placed either on liberal diets or on dairy-product-restricted diets.

MATERIAL AND METHOD:Infants aged 0 to 4 months old, who were exclusively breast-fed and whose mothers had a history of allergic disease, were the subjects of the present study. The mothers were randomized into two groups; mothers in a control group were on liberal diets, while mothers in an intervened group were on dairy product-restricted diets. Infants of both groups were examined for atopic dermatitis at seven days, one month, and four months of age.

RESULTS:There were 32 and 30 infants in the control and intervened groups, respectively. Eight infants in the control group and two infants in the intervened group developed atopic dermatitis by the age of four months. The prevalence of atopic dermatitis in the intervened group was significantly lower than that in the control group (6.67% vs. 25%, p<0.05).

CONCLUSION:Dairy product restriction in allergic mothers results in decreasing prevalence of atopic dermatitis in 4-month-old infants who were exclusively breast-fed.