8. Prevention
As the underlying skin barrier defects observed in AE are the first step
in the atopic march, the prevention of AE is very appealing - and
especially in families with known risk factors – highly important. As
emollients are the primary management strategy in AE, emollient
application at early age is an obvious prevention method for AE.
Contradictory data exists on its efficiency. Whereas earlier studies
hinted towards a highly effective approach for AE prevention in
neonates, this could not be confirmed in recent studies where no
evidence was found that daily emollients had a preventive effect in
neither a population-based nor a high-risk cohort [145-150]. One
factor for the conflicting results could be the formulation of the
ointment. Ceramide-based emollients are more efficient in reducing the
TEWL, whereas peanut-oil based ointments were reported to be a
facilitator for allergy [115, 151]. Due to the barrier defect,
emollient components can most likely cross the skin barrier more easily
in AE. Even though early supplementation of peanut, cow milk, wheat and
eggs was not protective for AE [146], a diverse diet and cheese
consumption seem to be beneficial, possibly due to the high microbial
diversity found in cheese [152, 153]. In the same direction, pre-
and probiotics are potentially protective for AE development [154].
Whereas prebiotics are non-digestional ingredients which promote
beneficial bacteria such as Bifidobacterium and Lactobacilli, probiotics
are active bacteria which are beneficial for human health [155,
156]. Among them are Bifidobacterium and Lactobacilli ,
Gram positive, anaerobic bacteria which are potentially capable of
producing lactic-acids and antimicrobial substances and bacteriocins,
limiting potentially pathogenic gut bacteria [154]. The data on the
efficiency of pre- and probiotics is highly controversial, likely due to
differences in type or mixture of strains [157]. Orally applied
prebiotic Escherichia coli and Enterococcus faecalis in
children were ineffective in AE prevention[158]. Contrarily, the
administration of probiotics during pregnancy has been confirmed to
prevent AE of the children in a meta-analysis of 19 studies [159].
Continuation of probiotics during breastfeeding and then the infant
seemed efficient in reducing the risk of AE [157, 160].