Diagnostic approach and management of cow's-milk protein allergy in infants and children: ESPGHAN GI Committee practical guidelines.

OBJECTIVES: This guideline provides recommendations for the diagnosis and management of suspected cow's-milk protein allergy (CMPA) in Europe. It presents a practical approach with a diagnostic algorithm and is based on recently published evidence-based guidelines on CMPA. DIAGNOSIS: If CMPA is suspected by history and examination, then strict allergen avoidance is initiated. In certain circumstances (eg, a clear history of immediate symptoms, a life-threatening reaction with a positive test for CMP-specific IgE), the diagnosis can be made without a milk challenge. In all other circumstances, a controlled oral food challenge (open or blind) under medical supervision is required to confirm or exclude the diagnosis of CMPA. TREATMENT: In breast-fed infants, the mother should start a strict CMP-free diet. Non-breast-fed infants with confirmed CMPA should receive an extensively hydrolyzed protein-based formula with proven efficacy in appropriate clinical trials; amino acids-based formulae are reserved for certain situations. Soy protein formula, if tolerated, is an option beyond 6 months of age. Nutritional counseling and regular monitoring of growth are mandatory in all age groups requiring CMP exclusion. REEVALUATION: Patients should be reevaluated every 6 to 12 months to assess whether they have developed tolerance to CMP. This is achieved in >75% by 3 years of age and >90% by 6 years of age. Inappropriate or overly long dietary eliminations should be avoided. Such restrictions may impair the quality of life of both child and family, induce improper growth, and incur unnecessary health care costs.

Microarray and allergenic activity assessment of milk allergens.

BACKGROUND: Cow's milk is one of the most common causes of food allergy affecting approximately 2.5% of infants in the first years of their life. However, only limited information regarding the allergenic activity of individual cow's milk allergens is available. OBJECTIVE: To analyse the frequency of IgE reactivity and to determine the allergenic activity of individual cow's milk allergens. METHODS: A nitrocellulose-based microarray, based on purified natural and recombinant cow's milk allergens was used to determine IgE reactivity profiles using sera from 78 cow's milk-sensitized individuals of varying ages. The allergenic activity of the individual allergens was tested using patients' sera for loading rat basophil leukaemia cells (RBL) expressing the α-chain of the human receptor FcεRI. RESULTS: Using the microarray and the RBL assay, cow's milk allergens were assessed for frequency of IgE recognition and allergenic activity. Moreover, the RBL assay allowed distinguishing individuals without or with mild clinical reactions from those with severe systemic or gastrointestinal symptoms as well as persons who grew out cow's milk allergy from those who did not. CONCLUSIONS: Component-resolved testing using milk allergen microarrays and RBL assays seems to provide useful additional diagnostic information and may represent a basis for future forms of prophylactic and therapeutic strategies for cow's milk allergy.

Serum tryptase and urinary 1-methylhistamine as parameters for monitoring oral food challenges in children.

To study the usefulness of urinary 1-methylhistamine and serum tryptase concentration as monitoring parameters in clinical settings, we investigated 32 children with atopic dermatitis and suspected food allergy during oral food challenges with eggs and cow's milk. Urinary 1-methylhistamine (MH) excretion increased significantly within 1 h after positive oral food challenges (p < 0.006), but showed considerable variation in negative challenges. MH seems to be a sensitive parameter (92.8%), but its specificity is insufficient (37.7%). In the group of 16 positive oral food challenges serum tryptase concentration increased significantly (p < 0.02) directly after provocation and remained elevated up to 2 h after provocation. No variation was observed in negative challenges or nonatopic controls. Serum tryptase concentration seems to be specific for marked clinical reactions after oral food challenges (100%), but its sensitivity was low (25%) and not superior to evaluation by clinical means. We conclude that, despite positive results for the group of children, MH and serum tryptase concentrations are not useful parameters for monitoring oral food challenges in an individual child due to insufficient sensitivity and specificity.