Salivary Microbiota Associated with Immunoglobulin A Nephropathy

This study aimed at investigating the salivary microbiota of 28 patients affected by immunoglobulin A nephropathy (IgAN). Fourteen healthy volunteers (HC) were used as control. Compared to HC, the number of some cultivable bacteria groups (e.g., total anaerobes) significantly ( P < 0.05) decreased in the salivary samples of IgAN patients. Total bacteria from salivary samples of IgAN patients and HC subjects were analyzed by pyrosequencing of 16S rRNA gene. Paired t test showed no significant ( P > 0.05) differences of alpha-diversity parameters (OTU, ACE, Chao1, and Shannon index) between the salivary samples of HC and IgAN patients. The difference for the community structure was further analyzed using three phylogeny-based beta-diversity measures. Compared to HC, the ratio between Firmicutes/Proteobacteria markedly decreased in IgAN patients. Gemella haemolysins , Granulicatella adiacens , and Veillonella parvula were positively associated ( P < 0.05) with HC. Within the phylum Bacteroidetes, Prevotella species ( Prevotella nigrescens , Prevotella intermedia , Prevotella pallens , and Prevotella salivae ) were the highest in HC. The only exception was for Prevotella aurantiaca . Compared to HC, the percentage of abundance of some species, belonging to Pasteurellaceae family (e.g., Haemophylus parainfluenzae ), increased in IgAN patients. Fusobacteriaceae ( Fusobacterium ) and Corynebacterium sp. also differed between the salivary samples of HC and IgAN patients.