Tongue Microbiota in Children with Geographic Tongue: A Pilot Case–Control Study

This study aimed to explore the characteristics of tongue microbiota in children with geographic tongue (GT) and provide microecological evidence for elucidating the occurrence and progression mechanism of GT. 16S rDNA high-throughput sequencing combined with bioinformatic analysis was adopted to compare the species differences of tongue microbial communities between children with GT and healthy children. The microbial richness of tongue coating in children with GT was markedly lower than that in healthy children ( p < 0.05). Species analysis revealed that the dominant genera in healthy children’s tongue coating were Prevotella , Veillonella , and Actinomyces , while the tongue coating of children with GT was predominated by Neisseria , Pasteurellaceae , and Streptococcus . Kyoto Encyclopedia of Genes and Genomes functional pathway enrichment analysis demonstrated an overall downregulation trend of metabolic functions in tongue coating microbiota of children with GT, with main differential pathways in histidine metabolism and teichoic acid biosynthesis. These results indicate that the onset of GT is highly correlated with abnormal enrichment of Neisseria , Pasteurellaceae , and Streptococcus . Imbalance of the tongue coating microbial communities may be involved in the development of GT.