RESEARCH DESIGN & METHODS: Here, we present an interesting case of a 22-year-old woman treated with FMT primarily to treat recurrent Clostridioides difficile infection, which coincidentally alleviated her ADHD symptoms. We also present the pre- and post-FMT gut microbiota profiles conducted using shotgun metagenomic sequencing on the patient's fecal samples to thereby highlight potential microbial-associated mechanisms associated with the relief of ADHD symptoms.
RESULTS & CONCLUSIONS: Our case report provides preliminary evidence regarding the use of FMT in a patient with C. difficile and ADHD. We speculate that gut microbiome modulation, in particular the gain or loss of specific microbial species and pathways involving the metabolism of SCFAs, tryptophan and GABA, may merit further exploration as a potential therapeutic strategy for ADHD.