Microbiome composition changes in health and disease

An increasing number of studies show that microbiome communities shift in patients with various chronic inflammatory conditions. These microbial community imbalances – often referred to as microbiome dysbiosis – have been associated with a growing number of inflammatory conditions and cancers.

Some studies demonstrate direct relationships between microbiome composition and disease onset. For example, Amar and team studied a group of patients and found that levels of microbial ribosomal DNA in the blood were significantly elevated in those who went on to develop diabetes.

Studies of microbiome dysbiosis demonstrate changes in the composition of entire microbial ecosystems. This suggests that chronic inflammatory disease processes resulting from persistent infection are not due to acquisition of any single pathogen. It follows that Koch’s postulates, which dictate that one microbe must cause a single disease state, may no longer be relevant in the era of the metagenome.