FFinalistSouthampton · 2027
Endocrine
AKT · Endocrine/Diabetes & glucose

Diabetic nephropathy

Microvascular glomerular damage from chronic hyperglycaemia

Overview

Progressive glomerular damage from diabetes — the leading cause of end-stage renal disease. Earliest marker is moderately increased albuminuria (raised ACR); progresses through proteinuria to declining eGFR. Slowed by glycaemic and BP control with renin-angiotensin blockade and SGLT2 inhibition.

Recognise

  • Rising urine albumin:creatinine ratio (ACR) — the earliest sign — then frank proteinuria and falling eGFR
  • Often with retinopathy (the two track together); hypertension
  • Progresses to CKD/ESRD; nephrotic-range proteinuria in advanced disease

Red flags

  • Rapidly rising creatinine, haematuria, or absence of retinopathy → consider a non-diabetic renal cause (refer/biopsy)
  • Hyperkalaemia/AKI on ACE-i/ARB → monitor U&Es

Differentials & how to tell them apart

Hypertensive nephrosclerosislong-standing hypertension without the diabetic microvascular picture
Other glomerulonephritishaematuria, rapid decline, no retinopathy → biopsy
Renovascular diseaseeGFR fall on ACE-i, asymmetric kidneys, vascular disease

Investigations

Annual ACR (early-morning) and eGFR; BP. Retinal screen (retinopathy usually coexists). Exclude other causes if atypical.

Management

ACE-inhibitor/ARB for albuminuria + SGLT2 inhibitor + tight glucose/BP control

  1. 1Optimise glucose and BP. Start an ACE-inhibitor or ARB once ACR is raised (titrate to max tolerated); add an SGLT2 inhibitor for additional renoprotection.Gate: Do NOT combine an ACE-inhibitor with an ARB; monitor U&Es/potassium after starting/up-titrating (a small creatinine rise is expected, but a >25–30% rise or hyperkalaemia means stop/seek advice)
  2. 2Refer to nephrology for advanced CKD/uncertain cause; manage CKD complications; prepare for renal replacement in ESRD.
ACE inhibitor or ARB — first-line for albuminuria — renoprotective; monitor U&Es/K+; not combined together
SGLT2 inhibitor — add for CKD with albuminuria — slows progression independent of glucose
Tight glycaemic + BP control — the foundation; BP target lower with albuminuria

Key points

ACR is the early signal and retinopathy usually accompanies it — its ABSENCE should make you doubt a purely diabetic cause. ACE-i/ARB + SGLT2 are the renoprotective spine.

Monitor & prognosis

Annual ACR/eGFR; U&Es after RAS blockade changes.

Slowed but not reversed; leading cause of ESRD.

Source: NICE NG28/NG203 (CKD); SGLT2 renal trials