CKD is defined as kidney damage or glomerular filtration rate (GFR) <60 mL/min/1.73 m(2) for 3 months or more, irrespective of cause. Kidney damage in many kidney diseases can be ascertained by the presence of albuminuria, defined as albumin-to-creatinine ratio >30 mg/g in two of three spot urine specimens.
Chronic kidney disease classification based upon glomerular filtration rate and albuminuria
| GFR stages | GFR (mL/min/1.73 m2) | Terms |
| G1 | ≥90 | Normal or high |
| G2 | 60 to 89 | Mildly decreased |
| G3a | 45 to 59 | Mildly to moderately decreased |
| G3b | 30 to 44 | Moderately to severely decreased |
| G4 | 15 to 29 | Severely decreased |
| G5 | <15 | Kidney failure (add D if treated by dialysis) |
| Albuminuria stages | AER (mg/day) | Terms |
| A1 | <30 | Normal to mildly increased (may be subdivided for risk prediction) |
| A2 | 30 to 300 | Moderately increased |
| A3 | >300 | Severely increased (may be subdivided into nephrotic and nonnephrotic for differential diagnosis, management, and risk prediction) |
The cause of CKD is also included in the KDIGO revised classification but is not included in this table.
GFR: glomerular filtration rate; AER: albumin excretion rate; CKD: chronic kidney disease; KDIGO: Kidney Disease Improving Global Outcomes.
Prognosis of CKD by GFR and Albuminuria Categories
| Prognosis of CKD by GFR and Albuminuria Categories: KDIGO 2012 |
Persistent albuminuria categories Description and range |
|||||
| A1 | A2 | A3 | ||||
| Normal to mildly increased |
Moderately increased |
Severely increased |
||||
| <30 mg/g <3 mg/mmol |
30-300 mg/g 3-30 mg/mmol |
>300 mg/g >30 mg/mmol |
||||
| GFR categories (ml/min/ 1.73 m2) Description and range |
G1 | Normal or high |
≥90 | |||
| G2 | Mildly decreased |
60-89 | ||||
| G3a | Mildly to moderately decreased |
45-59 | ||||
| G3b | Moderately to severely decreased |
30-44 | ||||
| G4 | Severely decreased |
15-29 | ||||
| G5 | Kidney failure |
<15 | ||||
Green: low risk (if no other markers of kidney disease, no CKD); Yellow: moderately increased risk; Orange: high risk; Red, very high risk.
References:
- National Kidney Foundation. K/DOQI clinical practice guidelines for chronic kidney disease: evaluation, classification, and stratification. Am J Kidney Dis. 2002 Feb;39(2 Suppl 1):S1-266. [Medline]
- Levey AS, Eckardt KU, Tsukamoto Y, Levin A, Coresh J, Rossert J, De Zeeuw D, Hostetter TH, Lameire N, Eknoyan G. Definition and classification of chronic kidney disease: a position statement from Kidney Disease: Improving Global Outcomes (KDIGO). Kidney Int. 2005 Jun;67(6):2089-100. [Medline]
- Summary of Recommendation Statements. Kidney Int Suppl (2011). 2013 Jan;3(1):5-14. [Medline]
Created Feb 24, 2023.
