Alterations in the human gut microbiome in anti‐N‐methyl‐D‐aspartate receptor encephalitis

Abstract Objective To explore the diversity and composition of the fecal microbiota in patients with anti‐N‐methyl‐D‐aspartate receptor (NMDAR) encephalitis. Methods We enrolled 10 patients in the acute stage with naïve treatment, seven patients with relapse, 13 patients without relapse in the remission phase, and 12 paired healthy controls. The fecal microbiota in different groups was compared by 16S ribosomal DNA (rDNA) gene pyrosequencing. Results Prominent dysbiosis in the gut microbiome of patients with anti‐NMDAR encephalitis was found. Our primary findings showed that the overall species richness (alpha diversity indexes) of the microbiota was higher in patients than in controls (P