Single low-dose exposure to cow's milk at diagnosis accelerates cow's milk allergic infants' progress on a milk ladder programme.

BACKGROUND: Cow's milk protein allergy (CMPA) is one of the most common food allergies in infancy. Most infants with CMPA tolerate baked milk from diagnosis and gradually acquire increased tolerance. Nevertheless, parents often display significant anxiety about this condition and a corresponding reluctance to progress with home introduction of dairy due to concerns about possible allergic reactions. OBJECTIVE: To evaluate the impact on gradual home introduction of foods containing cows' milk after a supervised, single low-dose exposure to whole milk at time of diagnosis. METHODS: Infants less than 12 months old referred with suspected IgE-mediated cow's milk allergy were recruited to an open-label randomized, controlled trial of intervention-a single dose of fresh cow's milk, using the validated dose of milk that would elicit reactions in 5% of CMPA subjects-the ED05 - vs routine care. Both groups implemented graded exposure to CM (using the 12 step MAP Milk Tolerance Induction Ladder), at home. Parents completed food allergy quality of life questionnaires and State and Trait Anxiety Inventories (STAI). Main outcome measures were milk ladder position at 6 months and 12 months post-randomization. RESULTS: Sixty patients were recruited, 57 (95%) were followed to 6 months. By 6 months, 27/37 (73%) intervention subjects had reached step 6 or above on the milk ladder compared to 10/20 (50%) control subjects (p = .048). By 6 months, 11/37 (30%) intervention subjects had reached step 12 (i.e. drinking unheated cow's milk) compared to 2/20 (10%) of the controls (p = .049). Twelve months post-randomization, 31/36(86%) of the intervention group and 15/19(79%) of the control group were on step 6 or above. However, 24/37 (65%) of the intervention group were at step 12 compared to 7/20 (35%) of the control group (p = .03). Maternal STAIs were significantly associated with their infants' progress on the milk ladder and with changes in skin prick test and spIgE levels at 6 and 12 months. CONCLUSION: This study demonstrates the safety and effectiveness of introduction of baked milk implemented immediately after diagnosis of cows' milk allergy in a very young cohort. A supervised single dose of milk at the ED05  significantly accelerates this further, probably by giving parents the confidence to proceed. Maternal anxiety generally reflects infants' progress towards completion of the milk ladder, but pre-existing high levels of maternal anxiety are associated with poorer progress.

Single-dose oral challenges to validate eliciting doses in children with cow's milk allergy.

BACKGROUND: There is increasing interest in the use of eliciting doses (EDs) to inform allergen risk management. The ED can be estimated from the distribution of threshold doses for allergic subjects undergoing food challenges within a specified population. Estimated ED05 values for cow's milk (the dose expected to cause objective allergic symptoms in 5% of the milk-allergic population) range from 0.5 mg to 13.9 mg cow's milk protein. We undertook a single-dose challenge study to validate a predicted ED05 for cow's milk of 0.5 mg protein. METHODS: Participants were recruited from 4 clinical centres. Predetermined criteria were used to identify patients reacting to 0.5 mg cow's milk protein (approximately 0.015 mL of fresh cow's milk). Children over 1 year underwent formal challenge to cow's milk to confirm clinical reactivity. RESULTS: 172 children (median age 6.0 (IQR 0.7-11) years, 57% male) were included in this analysis. Twelve (7.0%, 95% CI 3.7%-11.9%) children experienced objective symptoms that met the predetermined criteria. One participant had mild anaphylaxis that responded to a single dose of adrenaline, the remainder experienced only mild symptoms with no treatment required. We did not identify any baseline predictors of sensitization that were associated with objective reactivity to the single-dose challenge using 0.5 mg cow's milk protein. CONCLUSIONS: These data support an estimated ED05 for cow's milk of 0.5 mg protein. Values for ED05 above 0.5 mg for cow's milk protein proposed for allergen risk management need to be reviewed.