ACTH	Adrenocorticotrophin
BAI	Beck anxiety inventory
BD	Bipolar disorder
BDI	Beck depression inventory
BDNF	Brain-derived neurotrophic factor
BMI	Body mass index
COVID-19	Coronavirus disease 2019
CRP	C-reactive protein
DASS	Depression anxiety stress scales
FMT	Fecal microbiota transplantation
FGID	Functional gastrointestinal disorders
GABA	Gamma-aminobutyric acid
HADS	Hospital anxiety and depression scale
HC	Healthy controls
HDRS	Hamilton depression rating scale
HPA axis	Hypothalamic-pituitary-adrenal axis
IBD	Inflammatory bowel disease
IBS	Irritable bowel syndrome
IgM	Immune globulin M
LPS	Lipopolysaccarides
MADRS	Montgomery-Åsberg depression rating scale
MDD	Major depressive disorder
OTU	Operational taxonomic unit
PANDAS	Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections
PHQ-9	Patient health questionnaire
PLS-DA	Partial least squares discriminant analysis
PSS	Perceived stress scale
PUFA	Polyunsaturated fatty acids
QoL	Quality of life
SCFA	Short-chain fatty acids
spp.	Species
YMRS	Young mania rating scale