Chronic kidney disease staging criteria

Many kidney disease patients find it difficult to detect problems in the early stages of the disease, which results in it being too late when the problem is discovered. If the disease can be detected and treated early, the cure rate can be greatly improved. Kidney disease can be divided into different stages according to the degree of kidney damage and the different content of elements in the body at the time of onset. Next, we will give you a detailed introduction to the staging standards of chronic kidney disease.

1. In the past, chronic renal failure was divided into the following stages from mild to severe according to the degree of renal function damage.

(1) Compensatory stage of renal insufficiency: When the damage to the renal unit does not exceed 50% of the normal level (creatinine clearance 50-80 ml/min), there is compensation of reserve renal function without increase of metabolites such as blood urea nitrogen, blood creatinine is maintained at normal levels, and there are no clinical symptoms except for increased nocturia.

(2) Decompensated renal failure: more than 50% of the renal units are damaged (creatinine clearance 50-20 ml/min), blood creatinine reaches 133-442 μmol/L (2-5 mg/dl), and blood urea nitrogen exceeds 7.1 mm01/L (20 mg/dl). Patients may have clinical manifestations such as weakness, poor appetite, and mild anemia.

(3) Renal failure stage: serum creatinine rises to 442-707 μmol/L (5-8 mg/dl, creatinine clearance rate decreases to 20-10 ml/min, blood urea nitrogen rises to 179-286 mmol/L (50-80 mg/dl), and patients develop anemia, water-electrolyte-acid-base imbalance and other clinical manifestations.

(4) Uremic stage: serum creatinine reaches 707 μmol/L (8 mg/dl) or above, creatinine clearance drops below 10 ml/min, blood urea nitrogen exceeds 286 mmol/L (80 mg/dl), and the patient has obvious acidosis, anemia and severe systemic symptoms.

2. In recent years, according to the internationally recognized K/DOQI guidelines, chronic kidney disease is clinically divided into 5 stages according to the level of glomerular filtration rate, among which stages 2 to 5 are different stages of chronic renal failure:

Stage 1: Renal damage: GFR is normal or increased [≥90ml/(min•1.73㎡)].

Stage 2: Renal damage with a slight decrease in GFR [60-90 ml/(min•1.73 m2)].

Stage 3: Moderate decrease in GFR [30-59 ml/(min•1.73 m2)].

Stage 4: Severe decrease in GFR [15-29 ml/(min•1.73 m2)].

Stage 5: Renal failure [GFR <15ml/(min•1.73㎡)].

Blood urea nitrogen is greatly affected by many factors such as protein intake, fever and gastrointestinal bleeding, and cannot be used alone as an indicator to measure the severity of renal function damage. Although blood creatinine is relatively stable, its level is low in the elderly and those with muscular atrophy. Creatinine clearance can be used as an indicator for the staging of chronic renal failure, which is helpful for appropriate treatment of patients.