Question

At which glomerular filtration rate (GFR) is dialysis typically indicated?

• A. $<$90 ml/min/1.73 m²
• B. $<$60 ml/min/1.73 m²
• C. $<$30 ml/min/1.73 m²
• D. $<$15 ml/min/1.73 m²

Hint:

CKD Stages by GFR: Stage 1 ($\ge 90$), Stage 2 ($60\text{--}89$), Stage 3 ($30\text{--}59$), Stage 4 ($15\text{--}29$), Stage 5 ($<15\text{ mL/min}/1.73\text{ m}^2$ $\rightarrow$ Indication for Dialysis Transplant).

Answer 1

The Correct Option is D

Concept:
Chronic Kidney Disease (CKD) is classified into five progressive stages according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines based on estimated Glomerular Filtration Rate (eGFR) and albuminuria.
Stage 5 CKD represents End-Stage Kidney Disease (ESKD) Kidney Failure, requiring Renal Replacement Therapy (RRT) such as dialysis or kidney transplantation.
Explanation:
• The KDIGO CKD stages are defined as:
- Stage 1: $\text{GFR} \ge 90\text{ mL/min}/1.73\text{ m}^2$ with evidence of kidney damage
- Stage 2: $\text{GFR } 60\text{--}89\text{ mL/min}/1.73\text{ m}^2$ (mild decrease)
- Stage 3a/b: $\text{GFR } 30\text{--}59\text{ mL/min}/1.73\text{ m}^2$ (moderate decrease)
- Stage 4: $\text{GFR } 15\text{--}29\text{ mL/min}/1.73\text{ m}^2$ (severe decrease; pre-dialysis preparation)
- Stage 5: $\text{GFR} < 15\text{ mL/min}/1.73\text{ m}^2$ (Kidney Failure ESKD)

• When the GFR falls below $15\text{ mL/min/1.73\text{ m}^2$}, conservative medical management typically becomes insufficient to maintain fluid, electrolyte, and acid-base homeostasis and prevent uremic toxicity.

• Initiation of chronic maintenance dialysis (peritoneal dialysis or hemodialysis) is indicated at this stage, particularly when accompanied by clinical signs of uremia (intractable nausea, pericarditis, encephalopathy), refractory hyperkalemia, severe metabolic acidosis, fluid overload, or growth failure in children.
Final Answer:
Dialysis and renal replacement therapy are indicated when the glomerular filtration rate falls below $15\text{ mL/min}/1.73\text{ m}^2$ (Stage 5 CKD).