Oral fungal dysbiosis and systemic immune dysfunction in Chinese patients with schizophreniaOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This cross-sectional study examined the oral fungal microbiota (mycobiome) in patients with schizophrenia compared to healthy controls. Researchers sampled tongue coating and used internal transcribed spacer 1 (ITS1) amplicon sequencing to characterize fungal communities. They also measured host immune markers with multiplex immunoassays to see whether fungal changes tracked with systemic inflammation.
Who was studied?
The study enrolled 118 Chinese patients with schizophrenia and 97 age-matched healthy controls. Fungal profiling was based on tongue coating samples from these participants. The abstract does not report additional demographic details such as sex distribution or illness duration.
What were the most important findings?
Schizophrenia patients had reduced oral fungal richness and significant differences in overall fungal community composition (beta-diversity) compared to healthy controls. Within the fungal community, two mycotypes emerged: a Candida-dominant type and a Malassezia-dominant type, with schizophrenia patients showing increased Malassezia and decreased Candida relative to controls. Patients also showed immune dysfunction, with elevated pro-inflammatory cytokines (IL-6, TNF-alpha) and chemokines (MIP-1alpha, MCP-1); the Malassezia mycotype correlated positively with these inflammatory markers, while the Candida mycotype correlated negatively with them.
What are the greatest implications of this study?
The findings suggest oral fungal dysbiosis, marked by a shift away from Candida toward Malassezia, may be linked to the systemic immune dysregulation seen in schizophrenia. Because these mycotypes tracked oppositely with inflammatory cytokines, oral fungal profiling could serve as a non-invasive diagnostic biomarker candidate for schizophrenia. The results also point toward the oral mycobiome as a potential axis connecting microbial dysbiosis to neuroimmune dysfunction, warranting further mechanistic and longitudinal study.