FMT intervention decreases urine 5-HIAA levels: a randomized double-blind controlled study

Area of Science:

• Gastroenterology
• Neuroscience
• Microbiology

Background:

• Autism spectrum disorder (ASD) is frequently associated with gastrointestinal (GI) problems and altered serotonin metabolism.
• Gut microbiota modulation via fecal microbiota transplantation (FMT) is an emerging therapeutic strategy for ASD.
• The precise impact of FMT on serotonin pathways and ASD symptomatology requires further elucidation.

Purpose of the Study:

• To assess the clinical efficacy of FMT in ameliorating GI and core ASD symptoms in children.
• To investigate alterations in urinary metabolite profiles, specifically serotonin metabolites, following FMT.
• To identify potential biomarkers for treatment response in ASD patients undergoing FMT.

Main Methods:

• A randomized, double-blind, placebo-controlled trial was conducted.
• Gastrointestinal Symptom Rating Scale (GSRS) and ASD-related symptom scales (CARS, ABC, SRS) were used for clinical assessments.
• Urinary metabolites, including 5-hydroxyindoleacetic acid (5-HIAA), were quantified using homogeneous enzyme immunoassays.

Main Results:

• FMT intervention led to significant improvements in GSRS, CARS, SRS, and ABC scores compared to placebo.
• The FMT group showed a significant reduction in urinary 5-HIAA levels (p=0.022).
• No significant changes were observed in other urinary metabolites within the FMT group.

Conclusions:

• Fecal microbiota transplantation (FMT) demonstrates safety and efficacy in improving GI and core ASD symptoms in children.
• Reduced urinary 5-HIAA levels post-FMT suggest its potential as a biomarker for treatment response in ASD.
• FMT represents a promising therapeutic avenue for managing ASD-related symptoms and associated GI comorbidities.