3-HIBA	3-hydroxyisobutyrate
99mTc-DTPA	99mTc-diethylenetriaminepentaacetic acid
ACR	urinary albumin/creatinine ratio
ADKD	albuminuria DKD
AKI	acute kidney injury
ATP	adenosine triphosphate
BCAA	branched-chain amino acid
BEN	Balkan Endemic Nephropathy
CE	capillary electrophoresis
CE-MS	capillary electrophoresis mass spectrometry
CI	chemical ionization
CKD	chronic kidney disease
CKD-EPI	chronic kidney disease epidemiology collaboration
CRIC	chronic renal insufficiency cohort
CPMG	Carr–Purcell–Meiboom–Gill
DI-MS	direct injection mass spectrometry
DKD	diabetic kidney disease
EI	electron ionization
eGFR	estimated glomerular filtration rate
ESI	electrospray ionization
ESKD	end-stage kidney disease
GC	gas chromatography
GC-MS	gas chromatography-mass spectrometry
GFR	glomerular filtration rate
HESI	heated electrospray ionization
HILIC-LC-MS	hydrophilic interaction liquid chromatography-mass spectrometry
ICU	intensive care unit
IL-18	interleukin-18
KDIGO	Kidney Disease: Improving Global Outcomes
KIM-1	kidney injury molecule 1
LC	liquid chromatography
LC-MS	liquid chromatography-mass spectrometry
MS	mass spectrometry
NADKD	normoalbuminuric DKD
NAG	N-acetyl-beta-d-glucosaminidase
NGAL	neutrophil gelatinase-associated lipocalin
NIST	National Institute of Standards and Technology
NMR	nuclear magnetic resonance
NOESY	nuclear Overhauser effect spectroscopy
PAH	phenylalanine hydroxylase
Q-TOF-MS	quadrupole time-of-flight mass spectrometry
ROS	reactive oxygen species
RP	reverse phase
RP LC-MS	reverse-phase chromatography-mass spectrometry
RPD	renal pelvis dilatation
sCr	serum creatinine
SDM	simple diabetes mellitus group
SNR	signal-to-noise ratio
TCA cycle	tricarboxylic acid cycle
TCI	transmit coil decoupling using inverse detection
TMAO	trimethylamine N-oxide
TNF-a/EGF-R	tumor necrosis factor-alpha/epithelial growth factor receptor
TOF-MS	time-of-flight mass spectrometry
TQ-MS	triple quadrupole mass-spectrometer
UPJO	ureteropelvic junction obstruction
VOCs	volatile organic compounds