The CKD Reasoner

A single abnormal eGFR or ACR isn’t CKD — it might be a blip. Dehydration, acute illness, heart failure, urinary tract infection, heavy exercise, or a high-protein meal can all shift a one-off reading. That’s why NICE requires the abnormality to be confirmed on a repeat sample, persisting for more than 3 months, before you label someone with CKD.

• eGFR — repeat and confirm the fall is sustained, not a transient dip.
• ACR — ideally use an early-morning urine sample (less affected by posture and exercise); if the first ACR is 3–70 mg/mmol, confirm with a repeat sample.
• An acute, reversible cause (AKI) is a different diagnosis — CKD is the label once the abnormality has genuinely stuck around.

Exam habit: if a stem gives you only one reading with no timeframe, that’s the question testing whether you’ll jump to “CKD” too fast.

Albuminuria is an independent driver of risk — it moves you rightward across the grid whatever the eGFR.

NG238 advises offering atorvastatin 20 mg to everyone with CKD — the diagnosis itself raises cardiovascular risk, which is the commonest cause of harm in CKD.

Vaccination depends on CKD stage: the Green Book lists the annual influenza vaccine for anyone with CKD G3–G5, nephrotic syndrome or a kidney transplant, and a single pneumococcal vaccine (PPV23 or PCV20, using up local PPV23 stock first; Green Book chapter 25, updated August 2026) to those on dialysis or with CKD G4–G5, nephrotic syndrome or a kidney transplant — repeated every 5 years in this group.

Anyone approaching dialysis or transplant work-up should start the hepatitis B vaccination course early — response falls as kidney function declines, so timing matters.

The default target is <140/90. It tightens to <130/80 when albuminuria is heavy (ACR ≥70); NG203 sets no separate target for diabetes. This is the overarching goal — the ACEi/ARB below is usually how you get there.

Why: tighter control slows the loss of filtration and cuts cardiovascular risk, and heavy proteinuria marks faster-progressing disease.

An ACE inhibitor or ARB is driven by albuminuria, not the eGFR. NG203 advises one when:

• Diabetes with ACR ≥3 (A2 or A3),
• Hypertension with ACR over 30 (A3), or
• Any patient with ACR ≥70.

NG203: titrated to the highest licensed dose the person can tolerate — the antiproteinuric effect is the point.

SGLT2 inhibitors (e.g. dapagliflozin) sit alongside the ACEi/ARB: at an eGFR of 45–90, ACR ≥22.6 mg/mmol (upper A2 or A3) qualifies, as does type 2 diabetes at any ACR (NICE TA1075).

Independent eGFR trigger (NICE TA1075, July 2025): an eGFR of 20–44 now qualifies on its own — no ACR or diabetes needed. That covers all of G3b (30–44) and most of G4 (20–29), but not the bottom of G4 (15–19) or G5. If the category is G4, check the exact eGFR rather than assuming from the category alone.

They slow CKD progression and reduce cardiovascular and heart-failure risk independently of glucose lowering.

The statin needs no maths — every CKD patient gets one, regardless of ACR. Vaccines depend on CKD stage, not ACR. The rest climb the ACR number like a staircase — the lower rungs only trigger treatment if paired with a specific condition, but the top rung triggers it on its own, no matter what:

“Sugar needs 3, SGLT2 joins at 22, pressure needs 30, 70 stands alone.”

NICE TA1075 (dapagliflozin, July 2025; empagliflozin TA942 uses the same bands): there’s also an eGFR-only route onto an SGLT2 inhibitor — eGFR 20–44 qualifies on its own, no ACR or diabetes needed. It sits outside this staircase because it runs on the eGFR axis, not the ACR axis — think of it as a separate lift that also reaches the SGLT2 floor. If you want to learn the when and the why behind changes like this — read our blog.

Recheck eGFR and ACR more often the redder the square — roughly once a year in the milder squares, rising to two, three or four-plus times a year as filtration falls or albuminuria climbs (more still if things are unstable). The At a glance grid shows the exact figure for each square.