[Double-blind, placebo-controlled cow's milk challenge in children with alleged cow's milk allergies, performed in a general hospital: diagnosis rejected in two-thirds of the children]

Abstract

Objective: To present the results of double-blind, placebo-controlled food challenges with cow's milk in a general hospital.

Design: Retrospective chart review with a prospective protocol.

Method: Food challenges were performed between 1 December 2003 and 31 March 2005, consisting of 2 challenges separated by 1 week conducted in the out-patient hospital ward. Signs and symptoms that occurred during the food challenge and following reintroduction of cow's milk (if performed) were recorded.

Results: Food challenge was conducted in 43 children (23 boys and 20 girls) with a median age of 14 months. The challenge was not performed completely in 2 children. No anaphylactic reactions occurred. In all 41 patients a diagnosis ofcow's milk allergy had been made prior to referral to the paediatrician, based on symptoms, open elimination and challenge results. This diagnosis was rejected in 28 children (68%), based on negative results from the double-blind food challenge. Symptoms occurred during the placebo challenge in 10 children (24%), 8 of whom experienced symptoms identical to the presenting symptoms. After reintroduction of cow's milk, 2 recurrences of presenting symptoms were noted (possible late reactions).

Conclusions: Food challenge was conducted safely and effectively in a general hospital. Two-thirds of cases of cow's milk allergy diagnosed before referral were rejected based on the food challenge results. Many reactions attributed to cow's milk allergy did not appear to be caused by cow's milk allergy.