Renal Vein Thrombosis ✅
🩸 Renal Vein Thrombosis (RVT)
A serious complication most commonly associated with nephrotic syndrome.
Loss of anticoagulant proteins (antithrombin III, protein C, protein S) + ↑ procoagulant factors → hypercoagulable state.
📖 About
- Thrombosis of the renal vein draining the kidney.
- Can be unilateral or bilateral (bilateral → ↑ risk of AKI).
- Reducing proteinuria (e.g. ACEi/ARB) lowers overall thrombotic risk.
⚠️ Aetiology
- Nephrotic syndrome (esp. membranous nephropathy in adults).
- Loss of anticoagulants + ↑ fibrinogen, platelet activation, ↓ fibrinolysis.
- Trauma, dehydration, sepsis (especially neonates).
🔗 Associations
- Membranous nephropathy, lupus nephritis.
- Renal cell carcinoma (tumour invasion into renal vein).
- Systemic prothrombotic states (e.g. antiphospholipid syndrome).
🩺 Clinical Features
- Acute: flank pain, haematuria, AKI, enlarged kidney.
- Chronic: often asymptomatic.
- May present with pulmonary embolism.
🧪 Investigations
- 🩸 Nephrotic picture: proteinuria, hypoalbuminaemia, hyperlipidaemia
- 🫁 CT renal venography: investigation of choice
- 🧲 MRI venography if contrast contraindicated
- 🩺 Doppler USS: supportive but less sensitive
- 🧬 Renal biopsy: defines underlying glomerular disease
💊 Management
- Anticoagulation:
- Treat as VTE → at least 3–6 months
- Extend if ongoing nephrotic syndrome (persistent risk)
- LMWH → warfarin commonly used; DOACs increasingly used but evidence limited
- Underlying disease:
- ACEi/ARB → reduce proteinuria
- Immunosuppression depending on cause (e.g. membranous nephropathy)
- Supportive:
- Diuretics for oedema
- Statins for hyperlipidaemia
- Intervention:
- Thrombolysis/thrombectomy in severe acute bilateral RVT or worsening renal failure
📌 Clinical Pearls
- Think RVT in nephrotic patients with flank pain or PE.
- Membranous nephropathy = highest thrombosis risk.
- Hypercoagulability correlates with low serum albumin (<25 g/L).
📚 References
- KDIGO Clinical Practice Guideline for Glomerular Diseases
- UK Renal Association Guidelines
- BNF – Anticoagulation
