Paediatric Nephrotic Syndrome
Lesson Objectives
By the end of this lesson, learners should be able to:
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Define nephrotic syndrome and describe its diagnostic criteria.
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Identify primary and secondary causes of nephrotic syndrome in children.
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Recognize clinical features, including oedema, hypertension, and hematuria.
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Interpret laboratory investigations including urine protein, serum albumin, lipids, and immunologic markers.
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Outline supportive care, pharmacologic therapy, and steroid protocols.
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Define remission, relapse, frequent relapse, steroid dependence, and steroid resistance.
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Identify complications and preventive measures.
Description
Nephrotic syndrome is characterized by heavy proteinuria (>40 mg/m²/hr or 3+ on dipstick), hypoalbuminaemia (serum albumin <25 g/L), hyperlipidaemia, and oedema.
Common causes:
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Primary/idiopathic nephrotic syndrome
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Secondary nephrotic syndrome due to infections (Hepatitis B, malaria, syphilis), systemic disease (SLE)
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Congenital nephrotic syndrome (<3 months of age)
Clinical Features
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Oedema (periorbital, peripheral) with or without ascites
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Pleural effusions and generalized oedema (anasarca)
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Hypertension and haematuria may be present
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Weight gain due to fluid retention
Investigations
| Category | Tests / Findings |
|---|---|
| Blood | FBC/ESR, U&E, creatinine, LFTs including serum albumin, C3/C4, ANA, ASOT, anti-DNase B, RPR, HCV antibodies, HBsAg, triglycerides, cholesterol |
| Urine | Dipstick urinalysis, morning urine protein/creatinine ratio ≥0.2 g/mmol |
| Infectious / Immunologic | VZV IgG, Tuberculin skin test |
| Imaging | CXR, KUB ultrasound |
| Renal biopsy | Only if atypical: macroscopic hematuria, age <12 months or >12 years, low C3, vasculitic rash, suspected vasculitis |
Treatment
Supportive Care:
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No added salt in diet
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Diuretics: Furosemide 1 mg/kg twice daily; monitor intravascular volume
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Severe oedema: 20% albumin 1 g/kg over 4–6 hours, with monitoring for pulmonary oedema and hypertension
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Prophylactic antibiotics (penicillin; erythromycin if allergic) for gross oedema or ascites
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Daily weight and urinalysis monitoring
Pharmacologic Therapy:
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Prednisolone:
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Induction: 60 mg/m²/day (≈2 mg/kg) for 4 weeks
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Alternate-day therapy: 40 mg/m² (≈1.5 mg/kg) for 4 weeks
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Gradual taper over 4–6 weeks thereafter
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Antihypertensives: calcium channel blockers (amlodipine, nifedipine) preferred initially; ensure normal creatinine and potassium before ACE inhibitors
Definitions
| Term | Definition |
|---|---|
| Remission | Urine albumin nil/trace (<40 mg/m²/hr) for 3 consecutive days |
| Relapse | Urine albumin 2+ or more for 3 consecutive days after prior remission |
| Frequent relapse | ≥2 relapses in 6 months or >4 relapses in 12 months |
| Steroid dependence | Relapse while on steroids or within 14 days of discontinuation |
| Steroid resistance | No remission after ≥28 days of prednisolone at 2 mg/kg/day |
Complications
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Increased susceptibility to bacterial infections
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Spontaneous bacterial peritonitis
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Hypovolaemia and thromboembolism
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Chronic steroid-related: hypertension, obesity, growth retardation
Key Summary
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Nephrotic syndrome = proteinuria + hypoalbuminaemia + oedema + hyperlipidaemia
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Causes: primary, secondary, congenital
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Supportive care: diet, diuretics, albumin, antibiotics
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Prednisolone is mainstay of therapy
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Monitor for remission, relapse, steroid dependence/resistance
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Watch for infections, thromboembolism, and steroid complications