S5183 A Potential Microbiome Signature Showcasing Improvement of Autism in 2 Identical Twins

Introduction: This study explores the remarkable speech recovery in 2 identical twins, Twin A and Twin B, diagnosed with severe autism spectrum disorder and non-verbal status, over a 9-month microbiome-targeted intervention, focusing on the modulation of gut bacterial taxa. At baseline, both twins exhibited no verbal communication and significant microbial dysbiosis, with low levels of beneficial taxa and elevated levels of potentially harmful phyla, known to influence the gut-brain axis. The intervention aimed to increase beneficial microbes while reducing harmful ones, hypothesizing that these microbial shifts could improve neurological outcomes, including speech. Case Description/Methods: At baseline, both twins had near-zero levels (<0.05). By 1-month post-intervention, a slight increase was observed. At 9 months, Twin A showed a significant rise (phylum Actinomycetota ∼0.55, genus Bifidobacterium ∼0.50), while Twin B had a more modest increase (∼0.10). At baseline, Twin A had high levels (Verrucomicrobiota ∼0.035, Elusimicrobiota ∼0.02, Fusobacteriota ∼0.015), and Twin B showed slightly lower but elevated levels (Verrucomicrobiota ∼0.025, Elusimicrobiota ∼0.015, Fusobacteriota ∼0.01). By 9 months, Twin A’s harmful phyla were near zero, while Twin B maintained low levels (Fusobacteriota ∼0.005, others negligible). Discussion: Concurrently, both twins regained speech. By 9 months, Twin A, with the most significant microbial shifts, achieved advanced verbal communication, forming full sentences, engaging in conversations and reading. Twin B, with less pronounced changes, developed full functional speech but less reading capabilities. Both ATEC and CARS scores improved. These findings suggest a correlation between increased beneficial taxa, reduced harmful phyla, and speech recovery in severe atrial septal defect. The intervention likely alleviated neuroinflammatory stressors via the gut-brain axis, facilitating neurological improvements. This case study highlights the potential of microbiome-based therapies for ASD and calls for further research into microbial influences on neurodevelopmental outcomes.