Background: Multiple food intolerance in infants, including intolerance to extensively hydrolysed proteins (HP), is often difficult to treat. However, few data have been reported on clinical outcome and dietary treatment of these patients.
Aims: To evaluate the clinical characteristics of patients with HP-intolerance and the long-term outcome of treatment with ass' milk.
Patients and methods: This study included 21 HP-intolerant infants (15 males, median age at diagnosis 2 months) treated with an ass' milk-based diet and 70 cow's milk (CM) intolerant infants (40 males, median age at diagnosis 3 months) treated with casein hydrolysate milk-based diet. All patients were followed-up for a median period of 4 years. Both HP-intolerance and intolerance to other foods were diagnosed according to the double-blind placebo-controlled procedure. Formal CM-challenges were conducted at yearly intervals until tolerance was demonstrated. At diagnosis and after one year of the respective diets, the following growth parameters were determined: relative weight for sex and age, relative weight for height and height z-score.
Results: During the study period, multiple food intolerance was documented in 21/21 HP-intolerant infants (ass' milk group) and in 20/70 infants with CM-intolerance but tolerating HP (casein hydrolysate group) (P < 0.0001). In the ass' milk group, the more frequent food intolerances were toward soya, oranges, tomatoes and fish; goat's milk intolerance was demonstrated in five out of six patients receiving this food, and sheep's milk derivatives intolerance in four out of seven; these patients tolerated ass' milk. During the study period 3/21 patients in the ass' milk group became ass' milk intolerant; they showed vomiting (one cases) or diarrhoea (two cases). A lower percentage (52%) of patients in the ass' milk group became CM-tolerant during the study period than in the casein hydrolysate group (78%) (P < 0.01) and the age of the children at CM-tolerance was higher in the ass' milk than in the casein hydrolysate-treated children (P < 0.05). At diagnosis, a higher frequency of cases with elevated serum total IgE and specific IgE to CM antigens (P < 0.01) was observed in the ass' milk group. No difference was recorded between the two treatment groups in any of the growth parameters considered either at diagnosis or during the follow-up.
Conclusions: HP-intolerant patients showed a higher frequency of persistent food intolerance and of multiple food intolerance than patients tolerating casein hydrolysate. Ass' milk feeding was confirmed as a safe and valid treatment of the most complicated cases of multiple food intolerance.