Antibiotics, child microbiota and long-term health effects

Drug

Pediatrics

Antibiotic therapy is a cornerstone of the modern therapeutic arsenal but it displays a number of side effects, in particular a detrimental action on the human microbiota and the creation of a reservoir of antibiotic resistance genes (resistome). While the resistome is still under-investigated, the impact of dysbiosis caused by antibiotics is increasingly understood through scientific research, particularly in children. Let’s explain further.

About this article

Created 18 October 2019

Updated 25 November 2021

GUT MICROBIOTA HOMEOSTASIS AND HEALTH

The intestinal microbiota is a complex and diverse ecosystem composed of microorganisms coexisting with their host in a collaborative relationship. This microbiota plays an important part in the proper functioning of the digestive system, but also in metabolic and immune homeostasis. Its particularities made it a key component in human health and a significant research field aiming at exploring the consequences of antibiotics-induced dysbioses. A literature review provided a better understanding of the effects of antibiotics on the intra- and postpartum development of the intestinal microbiota in children.¹ During that period, exposure to antibiotics can take many different forms: mother treatment during pregnancy, cesarean delivery, postpartum treatment (especially in premature children), and even breastfeeding since antibiotics can change breast milk microbiota and/or be transmitted to the child.

THE GUT RESISTOME: AN AVENUE WORTH EXPLORING

The resistome designates all microbiota genes potentially coding for antibiotic resistance.
The growth of this gene reservoir has hardly been studied, but early acquired resistance could be related to the exposure to maternal and environmental microbes during and after birth.
The role of the resistome in the composition of the intestinal microbiota and its impact on individual or collective human health have yet to be defined.

HOST-MICROBIOTA INTERACTIONS: A SMALL WINDOW OF OPPORTUNITY

Several publications emphasize the importance of early intestinal colonization and the existence of a perinatal window of opportunity during which microbial exposure defines the “basic programming“ of the future microbiota, and consequently the long-term health of the child. The beginning and duration of this window of opportunity has not yet been documented and represents an active field of research. It is apparently short, however, and encourages a limited use of antibiotics to restrict adverse effects. Research shows that not all antibiotic drugs have the same effect on the microbiota and that individual sensitivity plays an important role in the impact on health. That being said, most children in developed countries are exposed to them during their first year of life. This observation calls for research to dig deeper into early dysbiosis caused by antibiotic therapies in order to better manage the associated metabolic and autoimmune disorders.

ANTIBIOTICS ARE PERINATAL DETERMINANTS

Newborns are colonized at a very early stage in life by aerobic bacteria and facultative anaerobic bacteria, and later, by strictly anaerobic bacteria from the maternal microbiota and the environment.
Antibiotics, as well as mode of delivery, gestational age or feeding method, have an impact on this colonization.
An antibiotic treatment of over 3 days is a risk factor for colonization by antibiotic resistant enteric bacteria, especially if a broad-spectrum drug is used.