Early-Life β-Lactam Exposure and the Developing Microbiome: Clinical Relevance and Controversies

Area of Science:

• Microbiology
• Pediatric Health
• Pharmacology

Background:

• Antibiotic-induced dysbiosis is linked to pediatric outcomes but lacks consistent definition.
• Early-life microbiome development is critical for long-term health.

Purpose of the Study:

• To critically evaluate data on early-life β-lactam antibiotic exposure and its effects on the developing microbiome.
• To synthesize current knowledge on microbiome alterations and potential health implications.

Main Methods:

• Conducted a narrative review of experimental and epidemiological studies.
• Included studies examining β-lactam exposure during pregnancy, perinatal period, and early childhood.

Main Results:

• β-lactams cause reproducible microbiome changes: decreased Bifidobacterium/Lactobacillus, increased Enterobacteriaceae.
• Reduced microbial diversity and altered short-chain fatty acid producers were observed.
• Associations with immune, metabolic, and neurodevelopmental outcomes are inconsistent and confounded.

Conclusions:

• Human causality for β-lactam-associated health outcomes remains limited, despite animal model evidence.
• Microbiome perturbations may increase susceptibility during critical developmental periods.
• Antibiotic stewardship is essential, emphasizing appropriate use and duration.