5-HTI	Serotonin
ABC	Aberrant Behavior Checklist
AEs	Adverse Events
ADHD	Attention Deficit Hyperactivity Disorder
ADI-R	Autism Diagnostic Interview—Revised
AGA	American Gastroenterological Association
ASD	Autism Spectrum Disorders
ATEC	Autism Treatment Evaluation Checklist
BBB	Blood–Brain Barrier
BSFS	Bristol Stool Form Scale
CARS	Childhood Autism Rating Scale
DA	Dopamine
CNBS-R2016	Chinese Neuropsychological and Behavioral Scale—Revised 2016
CNS	Central Nervous System
DSR	Daily Stool Record
FMT	Fecal Microbiota Transplantation
GABA	Gamma-Aminobutyric Acid
GI	Gastrointestinal Tract
GSRS	Gastrointestinal Symptom Rating Scale
HAMA	Hamilton Anxiety Rating Scale
HAMD	Hamilton Depression Rating Scale
HPA	Hypothalamic–Pituitary–Adrenal
IBS-D	Irritable Bowel Syndrome with Diarrhea
LGI	Lower Gastrointestinal Route
NGS	Next-Generation Sequencing
NJT	Nasojejunal Tube
PGI-II,III	Parent Global Impressions II,III
SAS	Social Adjustment Scale
SCFAs	Short Chain Fatty Acids
SCL-90	Symptom Checklist-90
SDSC	Sleep Disturbance Scale for Children
SRS	Social Responsiveness Scale
TET	Transendoscopic Enteral Tube
UDP-GlcNAc	Uridine Diphosphate N-Acetylglucosamine
VABS-II	Vineland Adaptive Behavior Scales, Second Edition
WMT	Washed Microbiota Transplantation