Antibiotic use and infant skin microbiome
There has been some evidence from
meta-analyses for the link between antibiotic use in pregnancy (n=18
studies)47 and early life (n=22
studies)48 and infant AD. These studies varied
considerably in design, ranging from cohort studies to case-control
studies and retrospective medical record reviews, yielding high
heterogeneity. Wan et al47 in particular showed that
significant links were demonstrated only for retrospective studies but
not for prospective or cross-sectional studies, suggesting that a degree
of ascertainment bias may exist. Confounding by indication may also be
present in studies where the indication for antibiotic prescriptions may
be due to early skin disease or infections. The meta-analyses were also
not able to delineate the specific at-risk window in pregnancy or early
life where antibiotic administration might conclusively increase the
risk of infant AD.
It has also been shown that the skin microbiome in healthy adults
receiving antibiotic treatment manifested greater changes, as
demonstrated by increased Bray-Curtis dissimilarities after treatment
compared to baseline.49 Longer antibiotic courses
induced more profound and persistent changes, suggesting that there was
also a dose/duration-dependent effect.
Antenatal, perinatal, and postnatal antibiotic exposure may
theoretically likewise cause perturbations in the host microbiome and
this has been demonstrated in gut microbiome
studies.50 There is, however, limited data describing
the impact of maternal antibiotic exposures on their infants’ skin
microbiome and its potential impact on infant AD. Hence, definitive
conclusions on whether the skin microbiome plays any role in the weak
link between maternal and early life antibiotic exposures and infant AD
cannot be made.