chronic kidney disease

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staging

GFR categories

albuminuria categories

KDIGO risk heat map

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renoprotective strategies

RAS blockade

ACEi or ARB — first-line for CKD with albuminuria (A2–A3). Titrate to maximum tolerated dose. Accept up to 30% rise in creatinine after initiation; beyond that, investigate renal artery stenosis.

• Hold in AKI, volume depletion, hyperkalaemia >5.5 mmol/L
• Do not combine ACEi + ARB (ONTARGET — no benefit, more hyperkalaemia and AKI)

SGLT2 inhibitors

Add regardless of diabetes status if eGFR ≥20 mL/min/1.73 m² and ACR ≥20 mg/mmol (or eGFR 20–45 even without significant albuminuria per EMPA-KIDNEY).

• DAPA-CKD (2020) — dapagliflozin reduced sustained ≥50% eGFR decline, ESKD, or renal/CV death by 39% vs placebo; benefit in diabetic and non-diabetic CKD
• EMPA-KIDNEY (2023) — empagliflozin reduced progression or CV death by 28%; included patients with eGFR 20–45 without significant albuminuria
• CREDENCE (2019) — canagliflozin in diabetic nephropathy; 30% reduction in primary renal composite

Expect an initial eGFR dip of 3–5 mL/min (haemodynamic, not injury) — do not stop for this. Withhold perioperatively and in acute illness (sick-day rules).

finerenone (non-steroidal MRA)

Add in type 2 diabetes with CKD (eGFR ≥25, K⁺ <5.0 mmol/L, ACR ≥3 mg/mmol) already on maximised RAS blockade.

• FIDELIO-DKD (2020) — 18% reduction in kidney composite endpoint
• Monitor K⁺ at 1 month and regularly; hold if K⁺ >5.5 mmol/L

BP targets

<120/80 mmHg (KDIGO 2024, standardised office measurement). Tolerate higher targets if symptomatic hypotension, advanced age/frailty, or eGFR declining with lower BP.

other measures

• Statin or statin/ezetimibe for all CKD G3–G5 not on dialysis (SHARP trial)
• Sodium restriction <2 g/d (≈5 g NaCl) — potentiates RAS blockade
• Protein: avoid high-protein diets; 0.8 g/kg/d in G4–G5 (controversial, modest benefit)
• Glycaemic control in diabetes — HbA1c ≤53 mmol/mol (≤7%); individualise in advanced CKD (hypoglycaemia risk increases as renal clearance of insulin falls)
• Avoid nephrotoxins: NSAIDs, aminoglycosides, iodinated contrast without hydration

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outpatient assessment framework

history — nephrology-specific

• Creatinine and ACR trend — start with a one-line trajectory summary
• Duration and control of diabetes (HbA1c, microvascular complications) and hypertension (home readings)
• NSAID use — ask by brand name (patients often don’t recognise “NSAID”)
• PPI use — common cause of AIN; question ongoing need
• Lower urinary tract symptoms, UTI history
• Vasculitic screen: joint pain, rashes, oral ulcers, haematuria
• Volume status symptoms: dyspnoea, orthopnoea, PND, peripheral oedema
• Previous AKI episodes and circumstances

examination

• BP both arms (sitting) + standing (one arm) — retake elevated readings after settling
• Volume status: JVP, lung crackles, peripheral oedema
• Weight trend for diuresis assessment

investigations

• Trend creatinine and ACR over time
• Urinalysis — blood (glomerular source?), protein
• HbA1c trend in diabetes
• Renal US if not done — size, echogenicity, obstruction
• Consider: calcium, phosphate, PTH, vitamin D (G3b+); haemoglobin (G3+); iron studies

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nephrology referral indications

• eGFR <30 (G4–G5) or declining rapidly (>5 mL/min/yr sustained)
• ACR >60 mg/mmol (A3) or nephrotic-range proteinuria
• Persistent haematuria with proteinuria (glomerular disease likely)
• Refractory hypertension despite ≥3 agents
• Refractory hyperkalaemia or metabolic acidosis
• Suspected systemic disease affecting kidneys (vasculitis, myeloma, amyloid)

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traps

• Stopping ACEi/ARB for a modest creatinine rise — up to 30% increase is expected and acceptable. Stopping prematurely removes long-term renoprotection.
• Ignoring albuminuria when eGFR is normal — A3 albuminuria with G1 eGFR is still high-risk CKD. ACR drives prognosis independently of GFR.
• Attributing all CKD to diabetes/hypertension without confirmation — atypical features (active sediment, rapid decline, no retinopathy in a diabetic with advanced nephropathy) warrant biopsy consideration.
• NSAIDs in CKD — patients self-medicate without mentioning it. Ask by brand name every visit.
• Forgetting sick-day rules — patients on ACEi/ARB + SGLT2i + diuretics need a clear plan to hold these during acute illness (vomiting, diarrhoea, febrile illness).

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key trials

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related: acute kidney injury · nephrotic syndrome · hyponatraemia · hyperkalaemia · dialysis overview