Successful introduction of milk after a negative double-blind placebo-controlled food challenge test is independent of the total dose and milk product used during the challenge test.

Background: Failure of milk introduction after a negative food challenge test is reported in a substantial number of patients. For this reason, guidelines recommend that the total dose of milk protein for a food challenge test should be comparable to a normal serving.

Objective: Our aim is to compare the success rate of milk introduction after a negative double-blind placebo-controlled challenge test performed with different doses of milk protein and different milk products.

Methods: We conducted a retrospective chart review of 485 patients challenged with a low or high dose of milk protein. Pasteurized milk and milk protein powder were used for the low-dose challenge tests, and condensed milk for the high-dose challenge tests. Successful introduction was defined as regular milk consumption, and discontinuation of further introduction due to the reappearance of symptoms as unsuccessful introduction. We also evaluated the association between milk products and successful introduction.

Results: The outcome of 288 (59.4%) double-blind placebo-controlled food challenge tests was negative. There were no significant differences between the low and high dose of milk protein in patient characteristics, percentage of patients lost to follow-up (15% vs 20%), in whom introduction had not yet been performed (4% vs 3.1%), reappearance of symptoms (18% vs 17%), and successful introduction (88.0% and 83.4%). Age, gender, specific immunoglobulin E for milk, dose of milk protein, and atopy were not associated with successful introduction. Children who experienced symptoms during the introduction were less likely to consume milk (P < .001). There was a nonsignificant trend toward higher successful introduction rate if pasteurized milk was used as test material compared to milk protein powder, and condensed milk.

Conclusion And Clinical Relevance: Successful introduction of milk after a negative challenge test is independent of the total dose of milk protein, and milk product used during the challenge test.