What are the stages of kidney failure and their corresponding treatments?

Kidney Failure Stages and Treatment

Chronic kidney disease is classified into five stages based on glomerular filtration rate (GFR), with each stage requiring progressively more intensive interventions to reduce cardiovascular mortality and slow disease progression. 1

CKD Stage Definitions

Stage 1: GFR ≥90 mL/min/1.73 m²

• Requires evidence of kidney damage (proteinuria, hematuria, structural abnormalities on imaging, or pathological findings on biopsy) to diagnose CKD at this stage 1
• GFR alone is insufficient for diagnosis without markers of kidney damage 2

Stage 2: GFR 60-89 mL/min/1.73 m²

• Requires evidence of kidney damage in addition to mildly decreased GFR 1
• Markers include albumin-to-creatinine ratio >30 mg/g, abnormal urine sediment, or imaging abnormalities 1

Stage 3: GFR 30-59 mL/min/1.73 m²

• Diagnosis based on GFR alone, regardless of kidney damage markers 1
• Subdivided into Stage 3a (GFR 45-59) and Stage 3b (GFR 30-44) 1, 3
• Complications including hypertension, anemia, and bone disease become prevalent below GFR 60 1, 4

Stage 4: GFR 15-29 mL/min/1.73 m²

• Severe kidney function decline with hypertension prevalence approaching 80% 1
• Mandatory nephrology referral for co-management and preparation for renal replacement therapy 3

Stage 5: GFR <15 mL/min/1.73 m² or dialysis

• Kidney failure requiring renal replacement therapy (dialysis or transplantation) when uremic symptoms develop 1
• Approximately 98% of patients begin dialysis at GFR <15 mL/min/1.73 m² 1

Stage-Specific Treatment Approach

Stage 1 Treatment

• Screen high-risk patients (diabetes, hypertension, family history) for kidney damage markers 1
• Implement CKD risk reduction strategies: blood pressure control to <140/90 mmHg, glycemic control in diabetics, smoking cessation 1
• Treat underlying causes (glomerulonephritis, vasculitis) aggressively 1

Stage 2 Treatment

• Diagnose and treat comorbid conditions including diabetes and hypertension 1, 3
• Initiate cardiovascular disease risk reduction with statins and antiplatelet therapy when indicated 1
• Slow progression with ACE inhibitors or ARBs, particularly if proteinuria present 3

Stage 3 Treatment

• Estimate rate of progression by monitoring GFR every 3-6 months 1, 3
• Evaluate and treat complications: anemia (target hemoglobin based on symptoms), secondary hyperparathyroidism (monitor calcium, phosphorus, PTH), metabolic acidosis 1
• Adjust medication dosing for reduced GFR to prevent drug accumulation 1

Stage 4 Treatment

• Prepare for renal replacement therapy through patient education on dialysis modalities (hemodialysis vs peritoneal dialysis) and transplantation options 1, 3
• Create vascular access (arteriovenous fistula preferred) 6-12 months before anticipated dialysis need 5
• Intensify management of complications: erythropoiesis-stimulating agents for anemia, phosphate binders, vitamin D analogs for bone disease 1

Stage 5 Treatment

• Initiate renal replacement therapy when uremic symptoms develop (nausea, vomiting, altered mental status, pericarditis, fluid overload refractory to diuretics) 1
• Hemodialysis typically performed 3 times weekly; peritoneal dialysis performed daily by patient 5
• Evaluate for kidney transplantation, which offers superior survival compared to dialysis 5

Critical Clinical Considerations

Age-related GFR decline should not be dismissed as "normal aging" since decreased GFR in elderly patients remains an independent predictor of cardiovascular mortality and adverse outcomes 1, 3

The risk of cardiovascular death exceeds the risk of progressing to dialysis in early CKD stages, making cardiovascular risk reduction the primary mortality-reducing intervention 6

Multiple complications cluster together as GFR declines below 30 mL/min/1.73 m², requiring simultaneous management of hypertension, anemia, bone disease, and metabolic acidosis 1, 4

Common Pitfalls

• Relying on serum creatinine alone without calculating estimated GFR leads to missed diagnoses, especially in elderly or low-muscle-mass patients 2, 7
• Failing to recognize that iodinated contrast should be avoided in acute kidney injury but can be used in Stage 5 patients already on maintenance dialysis 1
• Delaying nephrology referral until Stage 5, when referral should occur at Stage 4 to allow adequate preparation for renal replacement therapy 3
• Assuming kidney damage markers are unnecessary for diagnosis in Stages 3-5, though they provide important prognostic information about disease progression 1, 4