Daily Changes in Composition and Diversity of the Intestinal Microbiota in Patients with Anorexia Nervosa: A Series of Three Cases.

Anorexia nervosa, a severe psychiatric illness, is associated with an intestinal microbial dysbiosis. Individual microbial signatures dominate in healthy samples, even over time and under controlled conditions, but whether microbial markers of the disorder overcome inter-individual variation during the acute stage of illness or renourishment is unknown. We characterized daily changes in the intestinal microbiota in three acutely ill patients with anorexia nervosa over the entire course of hospital-based renourishment and found significant, patient-specific changes in microbial composition and diversity. This preliminary case series suggests that even in a state of pathology, individual microbial signatures persist in accounting for the majority of intestinal microbial variation.