Gut microbiome alterations in Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS) suggests variation in the gut-brain axis and gut metabolic potential

Abstract

PANDAS, or Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections is a form of Children’s Post infectious Autoimmune Encephalopathy (CPAE), a neuropsychiatric condition characterized by the abrupt onset of diverse neuropsychiatric manifestations following streptococcal infection. It is an increasingly recognized neuropsychiatric disorder that affects a subset of children whose underlying etiology remains unclear. Gut microbiome plays a crucial role in its host brain development and is implicated throughout the life in neurobehavior and neurological disorders. Emerging evidence suggest gut dysbiosis resulting in altered intestinal flora can impair gut barrier and increase leakiness in the blood-brain barrier leading to inflammation. We aimed to investigate if the microbiome is altered in pediatric patients with PANDAS. Stool (n=19), oral (n=20) and nasal swabs (n=18) were collected from patients diagnosed with PANDAS or healthy controls (HC) and used for 16S analysis. 13 stool samples (7 HC and 6 PANDAS) samples were further used for shogun metagenomics and 17 for untargeted metabolomics (8 HC and 9 PANDAS). 16S rRNA gene sequencing identified significant difference in microbial α diversity, with lower Shannon H’ in PANDAS compared to HC (Welch’s t-test t(16.95)=-2.6, p=0.02), and in β-diversity (PERMANOVA R2=0.08 p=0.04) between PANDAS and HC fecal but not throat and nasal samples. Shotgun metagenomics identified a significant reduction in gene diversity (Welch’s t-test t(9.9)=-3.06, p=0.01) and changes in various KEGG ortholog modules involved in gut metabolism and gut-brain axis. Significant differences were also detected in metabolite composition (PERMANOVA R2=0.10, p=0.02). We also identified a set of microbial groups and metabolites enriched or depleted in CPAE patients, involved in different aspects of host physiology and gut metabolism. Our results show that PANDAS patients have an altered gut microbial community, which may exacerbate their behavioral symptoms and it should be taken into consideration in unveiling the complex pathogenesis and selection of treatment options. Arizona Department of Health Services RFGA2022-010-23 (PK) and ADHS17-00007403 (SR, MD); The Alex Manfull Fund (PK). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.