Chronic kidney disease is staged by two numbers, not one — filtration and albuminuria — and almost every complication traces back to four jobs the kidney stopped doing. Set the eGFR and the albumin‑to‑creatinine ratio and read the stage, then switch each lost function off and watch the exact signs, labs and nursing actions appear. Finish on the trap bench, where the answers are the ones students most often get backwards.
Set the two staging numbers
38
420
Where this patient sits
Why two numbers
Albuminuria is staged alongside GFR because it independently predicts progression and cardiovascular death. A patient at G2 with A3 is at higher risk than a patient at G3a with A1. When a student asks why we test the urine of a patient whose creatinine is normal, this is the answer.
Switch off a kidney function
How advanced is the uremia?
G4
The premise
Nephrons are lost, the survivors hyperfilter to compensate, that hyperfiltration scars them, and the disease becomes self‑sustaining. That is why treatment aims at lowering intraglomerular pressure rather than at the original insult — whatever it was.