Effect of a new synbiotic mixture on atopic dermatitis in infants: a randomized-controlled trial

Clinical trials investigating the therapeutic effect of probiotics on atopic dermatitis (AD) show inconsistent results. Better results can possibly be achieved by combining probiotics with prebiotics, i.e. synbiotics.

To investigate the therapeutic effect of a synbiotic mixture on the severity of AD in infants.

In a double-blind, placebo-controlled multi-centre trial, 90 infants with AD [SCORing Atopic Dermatitis (SCORAD) score > or =15], aged < 7 months and exclusively formula fed, were randomly assigned to receive either an extensively hydrolysed formula with Bifidobacterium breve M-16V and a galacto-/fructooligosaccharide mixture (Immunofortis), or the same formula without synbiotics for 12 weeks. The primary outcome was severity of AD, assessed using the SCORAD index. A secondary outcome measure was intestinal microbiota composition.

There was no difference in SCORAD score improvement between the synbiotic and the placebo group. The synbiotic group did have a significantly higher percentage of bifidobacteria (54.7% vs. 30.1%, P<0.001) and significantly lower percentages of Clostridium lituseburense/Clostridium histolyticum (0.5 vs. 1.8, P=0.02) and Eubacterium rectale/Clostridium coccoides (7.5 vs. 38.1, P<0.001) after intervention than the placebo group. In the subgroup of infants with IgE-associated AD (n=48), SCORAD score improvement was significantly greater in the synbiotic than in the placebo group at week 12 (-18.1 vs. -13.5 points, P=0.04).

This synbiotic mixture does not have a beneficial effect on AD severity in infants, although it does successfully modulate their intestinal microbiota. Further randomized-controlled trials should explore a possible beneficial effect in IgE-associated AD.