Kidney Disease: Improving Global Outcomes (KDIGO) kidney function and disease glossary: suggested terms to describe kidney function and kidney disease and criteria and measures defining them Preferred term Suggested abbreviationsa Rationale/explanation Terms to avoid Part 1. Kidney function and disease The term “kidney” should be used preferentially when describing kidney disease and kidney function, with exceptions Renal; the prefix “nephro-” (except in the setting of specific functions, diseases, or syndromes, see below) Kidney disease Reflects the entirety of acute kidney diseases and disorders and chronic kidney disease Renal disease; nephropathy (except in the setting of specific diseases, e.g., membranous nephropathy) Kidney function Reflects the entirety of different and complex physiological functions of the kidney; should not be equated with glomerular filtration rate (GFR) only Renal function (except when describing specific functions, e.g., renal acidification, renal concentrating mechanism) Normal kidney function General term applicable to various aspects of kidney function, which should be specified Abnormal kidney function General term applicable to various aspects of kidney function, which should be specified Renal/kidney impairment, insufficiency, dysfunction; azotemia Residual kidney function RKF Kidney function in people with kidney failure receiving KRT; further specification is required, e.g., urine flow rate, solute clearance. Although it is usually used in the setting of dialysis, this term could be used to refer to native kidney function in kidney transplant recipients. Residual renal function (RRF) Kidney structure Reflects the entirety of different and complex structures of the kidney, ascertained by imaging and markers of injury and damage Renal structure (except when describing specific structures within the kidney, such as artery, vein, capsule, parenchyma, cortex, medulla, glomeruli, tubules, interstitium, cysts, tumors) Normal kidney structure General term applicable to various aspects of kidney structure, which should be specified Abnormal kidney structure General term applicable to various aspects of kidney structure, which should be specified Causes of kidney disease Cause of AKI, AKD, and CKD should be indicated whenever possible. Cause may be known, presumed, or unknown. Method for ascertainment and attribution of cause should be specified. Cause should not be inferred only from presence of comorbid condition (such as diabetes) Preferred term Suggested abbreviationsa Rationale/explanation Terms to avoid Part 2. Kidney failure GFR 3 mo Chronic renal failure; chronic renal disease; chronic nephropathy; chronic renal/kidney impairment, insufficiency, dysfunction; azotemia; uremia; irreversible kidney failure Symptoms and signs Specification preferred (with, without, or unknown symptoms and signs); with symptoms and signs would be synonymous with uremia Uremia/uremic syndrome A syndrome consisting of symptoms and signs associated with kidney failure (does not indicate a causal role for urea) Treatment Specification required Kidney replacement therapyc KRT Further specification is required, includes dialysis and transplantation Renal replacement therapy (RRT) (Continued on next page) AS Levey et al.: KDIGO nomenclature for kidney function and disease KDIGO conference report Kidney International (2020) 97, 1117–1129 1123 Dialysis AKI stage 3D AKI stage 3 treated by dialysis AKI-D, dialysis-dependent AKI CKD G5D CKD G5 treated by dialysis ESKD, ESKF, ESRD, ESRF, dialysis-dependent CKD Duration Long-term vs. short-term: Long-term refers to dialysis for CKD; may also be referred to as maintenance dialysis. Short-term refers to dialysis for AKD Chronic dialysis, acute dialysis (the terms acute and chronic refer to duration of kidney disease rather than duration of dialysis treatment) Modality and frequency Modalities hemodialysis (HD) hemofiltration (HF) hemodiafiltration (HDF) peritoneal dialysis (PD, ambulatory or automated) Frequency continuous intermittent (short or prolonged) Kidney transplantation CKD G1T–G5T CKD G1–G5 after transplantation ESKD, ESKF, ESRD, ESRF Donor source Specify living donor kidney transplant/transplantation (LDKT) or deceased donor kidney transplant/ transplantation (DDKT) Kidney failure with replacement therapy KFRT CKD G5 treated by dialysis or CKD G1-G5 after transplantation; for epidemiologic studies, both should be included ESKD, ESKF, ESRD, ESRF Kidney failure without replacement therapy CKD G5 without KRT Further specification is preferred: specify whether KRT is not chosen vs. not available ESKD, ESKF, ESRD, ESRF, untreated kidney failure With comprehensive conservative care Further specification is preferred; definition is evolving Without comprehensive conservative care Further specification is preferred: specify whether comprehensive conservative care is not chosen vs. not available Preferred term Suggested abbreviationsa Rationale/explanation Terms to avoid Part 3. Acute kidney diseases and disorders (AKD) and acute kidney injury (AKI) Disease duration #3 mo; conceptually different from initial recognition of CKD Acute renal failure (ARF); acute renal insufficiency (ARI) Acute kidney diseases AKDc KDIGO definition: AKI, or GFR 50% for #3 mo ARF, ARI Acute kidney injury