[Standardized multidisciplinary diagnosis of cow's milk protein allergy in children. Work Group Cow's Milk Protein Allergy of the Groningen Academic Hospital].

Objective: Evaluation of standardized multidisciplinary diagnostic procedures for cow's milk allergy (CMA) in children.
Design: Prospective standardized study.
Setting: Beatrix Children's Hospital, Department of Allergology, Dermatology and Dietetics, University Hospital Groningen, the Netherlands.
Methods: From August 1991 until May 1993, 114 children suspected of CMA for the first time were investigated according to the protocol for diagnosis of CMA, together with 23 children, previously diagnosed as CMA, in whom CMA was re-evaluated. Of 114 children with first suspicion of CMA, 66 improved on a cow's milk-free diet. The remaining 48 were excluded from the study because of no improvement on a cow's milk free diet, no diet given, insufficient data or no follow-up. The protocol was evaluated by questionnaire sent to 10 representatives of the departments involved.
Results: In 26/66 (39%) children, the diagnosis of CMA was confirmed by cow's milk challenge. The eosinophilic granulocytes were higher (p = 0.04), both IgE RAST and Skin Prick Test (SPT) for cow's milk were more often positive (both p = 0.01) in CMA than in non-CMA. The sensitivity and specificity were 50%-82% for IgE RAST and 60%-84% for the SPT, respectively. Four of the 23 children still had CMA at re-evaluation. In three of them, a SPT was performed, which was positive in all. In 12 of the 19 children, without CMA at re-evaluation, a SPT was performed, which was negative in all. At 1, 2, 3 and 4 years of age 13%, 48%, 74% and 78%, respectively, of the re-evaluation CMA patients had developed tolerance for cow's milk. The use of the protocol was found important by the representatives involved, although some practical difficulties remain.
Conclusion: A multidisciplinary approach of CMA is possible. Improvement on a cow's milk-free diet by itself is not sufficient to diagnose CMA. Cow's milk challenge is obligatory. Laboratory investigations are of limited value. Re-evaluation of CMA after one year of age is necessary in view of the temporary character of CMA. When the SPT for cow's milk is positive, postponement of re-evaluation may be considered.