Related Subjects:
|Metabolic acidosis
|Lactic acidosis
|Acute Kidney Injury (AKI) / Acute Renal Failure
|Renal/Kidney Physiology
|Chronic Kidney Disease (CKD)
|Anaemia in Chronic Kidney Disease
|Analgesic Nephropathy
|Medullary Sponge kidney
|IgA Nephropathy (Berger's disease)
|HIV associated nephropathy (HIVAN)
|Balkan endemic nephropathy (BEN)
|Autosomal Dominant Polycystic kidney disease
🧾 Key Point: Minimal Change Disease (MCD) is the commonest cause of nephrotic syndrome in children.
✅ Prognosis is excellent – only ~1% progress to end-stage renal failure.
About 👶
- MCD = most common cause of nephrotic syndrome in children, especially boys under 5 years.
- Can occur in adults, but far less common.
- Strong steroid responsiveness ➝ good long-term outcome.
Causes & Triggers ⚡
- 🔹 Idiopathic in most cases (~80–90%).
- 🔹 Secondary causes (10–20%):
- 💊 Drugs: NSAIDs, rifampicin.
- 🦠 Infections: EBV (infectious mononucleosis).
- 🎗 Malignancies: Hodgkin’s lymphoma, NHL, thymoma.
Aetiology & Pathophysiology 🔬
- 👁 Electron microscopy: shows fusion/effacement of podocyte foot processes.
- ⚡ Loss of the negative charge of the GBM ➝ selective albuminuria.
- 📌 Associations: atopy, HLA-DR7, Hodgkin’s disease, NSAIDs.
Clinical Features 🤒
- 💧 Oedema: periorbital → peripheral → anasarca.
- 🍺 Frothy urine: due to heavy proteinuria.
- 🧪 Nephrotic syndrome triad: proteinuria, hypoalbuminaemia, hyperlipidaemia.
- ❌ Hypertension and haematuria are uncommon (contrast with other GN).
Investigations 🔍
- 🧪 U&E: usually normal.
- 💧 Urinalysis: highly selective proteinuria (>3 g/day, mainly albumin).
- 📉 Serum albumin: low (<25 g/L typical).
- ⬆️ Cholesterol/lipids: elevated.
- 🔬 Renal biopsy: not needed if classic presentation, but shows podocyte effacement on EM.
Management 🩺
- 💊 Steroids: Prednisolone 8 weeks then taper ➝ remission in ~90% children.
- 🔄 Relapses: occur in ~50% ➝ may require cyclophosphamide or ciclosporin.
- 💧 Supportive: fluid/salt restriction, diuretics for oedema, infection prophylaxis (pneumococcal vaccine >2yrs).
Prognosis 📈
- 🌟 Excellent with treatment – most achieve remission.
- ⚠️ Relapsing course common, but ESRF progression is very rare (~1%).
- 🦠 Infection (due to immunoglobulin loss) remains the main serious risk.
✨ Exam Pearl:
Child with sudden oedema, frothy urine, hypoalbuminaemia + hyperlipidaemia = MCD until proven otherwise.
👉 If hypertension + haematuria present, think other causes (e.g., FSGS, membranous GN).
Cases — Minimal Change Disease (MCD)
- Case 1 — Childhood nephrotic syndrome 🧒: A 5-year-old boy presents with periorbital swelling, frothy urine, and ankle oedema. Urine dip: 4+ protein, no blood. Serum albumin: 16 g/L, cholesterol elevated. Renal function normal. Diagnosis: nephrotic syndrome due to minimal change disease. Managed with high-dose oral corticosteroids; biopsy often deferred unless atypical features develop.
- Case 2 — Relapsing disease in adolescence 🔄: A 14-year-old girl with a history of childhood nephrotic syndrome presents again with oedema after a viral URTI. Urine: heavy proteinuria. Previous biopsy: minimal change disease. Diagnosis: relapsing MCD. Managed with repeat steroid therapy, with consideration of calcineurin inhibitor if frequent relapses.
- Case 3 — Adult secondary MCD 💊: A 42-year-old man develops sudden-onset nephrotic syndrome while being treated with NSAIDs for chronic back pain. Renal biopsy: minimal change disease. Diagnosis: secondary MCD due to NSAID use. Managed by stopping NSAID, starting steroids, and nephrology follow-up.
Teaching Point 🩺: Minimal change disease is the commonest cause of nephrotic syndrome in children, but can also affect adults. It is usually steroid-responsive. Secondary forms may be triggered by NSAIDs, lymphoma, or infections. Electron microscopy shows podocyte foot process effacement.