Table 1.

Randomized and non-randomized studies on the use of pre and probiotics for the prevention of atopic dermatitis in children.

References	Study Type	Population (N)	Time of exposure	Interventions	Outcomes
Penders et al. (22)	Prospective birth cohort (KOALA birth cohort)	957 infants at 1 month	Postnatal	Detection of gut microbiota composition in stool and total and specific IgE in venous blood	Associations between microbial composition and atopy at 2 years
Watanabe et al. (63)	Case-control	30 AD cases, and 68 controls	Postnatal	Detection of fecal microflora, fecal IgA concentrations, IgA on the skin surface	Differences in fecal microflora between patients with AD and healthy control subjects
Huang et al. (65)	Systematic review and meta-analysis of 13 RCTs	13 RCTs of children <18 years with confirmed AD	Postnatal	Scoring AD (SCORAD) assessment following probiotic administration	Effect of probiotics in the treatment of AD
Arslanoglu et al. (66)	RCT	134, high-risk infants	Postnatal	2 arms: 8 g/L scGOS/lcFOS) or placebo (8 g/L maltodextrin) during the first 6 mo of life	Allergic manifestations and infections during the first 2 years
Osborn and Sinn (67)	Systematic review of RCTs	4 RCTs, including 1428 infants	Postnatal	Prebiotic mixtures in low-risk and high-risk infants	Allergy outcomes in the first 2 years of life
Tam-lim et al. (68)	Systematic review and meta-analysis of RCTs	22 RCTs including 28 different strains	Postnatal	2 arms—strain mixes vs. placebo Mix1 (Bifidobacterium animalis subsp. lactis CECT 8145, Bifidobacterium longum CECT 7347, and Lactobacillus casei CECT 9104); Lactobacillus casei DN-114001; and Mix6 (Bifidobacterium bifidum, Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus salivarius)	Efficacy of probiotic strains compared to placebo, on pediatric atopic dermatitis