YVAN VANDENPLAS
Vrije Universiteit Brussel, Department of Pediatrics, UZ Brussel, 1090 Brussels, Belgium

Abstract

This review summarizes how the composition of the gastro-intestinal microbiota depends on pre- and postnatal factors, and birth itself. The impact of method of delivery, feeding during infancy and medications, such as antibiotics and anti-acid medication, on the composition of the gastro-intestinal microbiota has clearly been shown. However, the duration of the impact of these factors is not well established. The gastro-intestinal microbiome composition is associated with many auto-immune mediated diseases. Although causality has not been obviously demonstrated, there is a strong tendency in this direction. Nevertheless, results of the manipulation of the gastro-intestinal microbiome composition in these conditions are often disappointing. A better understanding on factors determining the long-term composition of the gastro-intestinal microbiome and its health consequences are a priority research topic. A better understanding of the association between the microbiome and the immune system may have a tremendous impact on general health.

INTRODUCTION

The microbiome is the ecological community of commensal, symbiotic, and pathogenic microorganisms that literally share our body space. This term was originally coined by Joshua Lederberg, who argued the importance of microorganisms inhabiting the human body in health and disease. A dysbiosis is condition with microbial imbalances “on” or “inside” the body. Dysbiosis is most prominent in the digestive tract or on the skin, but can also occur on any exposed surface or mucous membrane such as lungs, mouth, nose, sinuses, ears, nails, or eyes. Dysbiosis has been associated with different illnesses, such as gastroenteritis, allergy, inflammatory bowel disease, etc.

FACTOR INFLUENCING THE MICROBIOME BEFORE BIRTH
Current evidence does not support a major role for maternal dietary restrictions during pregnancy or lactation (1). However, there is some evidence that manipulation of the maternal gastrointestinal microbiota during pregnancy may have a health benefit for the offspring. A group of 256 women was randomized during the first trimester of pregnancy (2). Intensive dietary counseling provided by a nutrit ...