Background and aims Cow^’s milk protein allergy (CMPA) is the most common food allergy in children. Eliminating diet plays a key role in CMPA management and extensively hydrolyzed formulas are used. The aim of study was to compare the efficacy of whey extensively hydrolyzed formula (eWHF) and casein-based extensively hydrolyzed formula (eCHF) in infants with cow’s milk protein allergy.

Methods 66 infants (4 to 12 months of age) with moderate and severe forms of CMPA were divided into 2 groups and received either eWHF (n=20) or eCHF (n=46) during 5 week period. SCORAD index, specific-IgE levels, weight gain were evaluated before and after study.

Results Atopic dermatitis was present for 56.4% (37) infant, gastrointestinal (GI) symptoms took place in 8.8% (6), and combined skin and GI symptoms – in 34.8% (23) patients. Elevated specific-IgE level was found to bovine serum albumin (34.5%), casein (15.5%), β-lactoglobulin (19%) and to goat^’s milk protein (43.1%). Diagnostic levels of antibodies to eWHF were detected in 12.1% (0,250–0,292 ng/ml), to eCHF in none of patients (0042 ng/ml). SCORAD index decreased in eWHF group from 44.0 to 16.3 in moderate forms and from 73.1 to 50.7 in severe forms. In eCHF group these scores decreased from 42.9 to 5.3 and from 83.1 to 9.7 respectively (p<0.05). Due to balanced composition of both formulas an average food intake in eWHF group for protein was 3.1±0.79 g/kg, and in eCHF – 2.9±0.8 g/kg, and for energy 118±0.2 kcal/kg and 114±0.2 kcal/kg respectively. Weight gain in spite of eliminating diet was corresponding to age references (564±68 g per month for 4–6 months infants and 430±124 g per month for 7–12 months infants).

Conclusions Casein-based extensively hydrolyzed formula is both clinically and immunologically more effective for treatment of moderate and severe forms of CMPA in paediatric patients than whey extensively hydrolyzed formula. Infants feeding eCHF have demonstrated weight gain and tolerance.