Cow's milk-associated gastrointestinal symptoms evaluated using the double-blind, placebo-controlled food challenge

The aim of this study was to evaluate the suspicion of cow's-milk allergy in infants with unspecific gastrointestinal (GI) symptoms using the double-blind, placebo-controlled food challenge.

A prospective cohort study, which recruited 57 consecutive children with gastrointestinally manifested symptoms suspected of cow's-milk allergy. All patients underwent a 5-day double-blind, placebo-controlled food challenge for cow's milk.

The median age of the patients was 8.7 months. None had measurable cow's-milk-specific IgE. The food challenge was positive in 18 (32%) cases, with symptoms manifesting within 48 hours in 17 of 18 cases. The only symptom that correlated with the positive challenge was loose stools, reported as a presenting symptom in 78% of challenge-positive and in 46% of challenge-negative children (P = 0.043). During active challenge, the respective proportions were 82% and 2% (P < 0.0001). No serious adverse effects were manifested during the challenges. In the challenge-negative group, significant placebo reactions occurred in 18 (46%) patients. In the challenge-negative children, adult-type hypolactasia genotype CC frequency was higher (31%, P = 0.033) than national prevalence of 18%.

In an infant with unspecific GI symptoms suspected of cow's-milk allergy, this diagnosis is seldom confirmed. Other reasons for the troublesome GI symptoms should also be identified.