Nephrotic Syndrome Clinical Features • Severe proteinuria (>3.5g/day) • Low serum albumin due to proteinuria • Oedema • High serum lipids (loss of regulatory proteins through urine) Causes • Minimal change GN • Diabetic nephropathy • Primary/idiopathic and secondary membranous GN • Primary FSGS • Amyloidosis • Fibrillary glomerulopathy Assessment and Investigation • History: onset of symptoms, predisposing conditions (e.g. T2DM), frothy urine • Exam: periorbital and upper arm swelling, BP, autoimmune features (e.g. rash), pitting oedema • Urinalysis: large proteins, occasionally haematuria, glucosuria if T2DM involved • Investigations: serum albumin, EUC, timed urine collection or albumin to creatinine ratio, kidney biopsy • Treatment: depends on cause, paeds usually responsive to prednisolone, some adult forms respond to immunosuppressants Percutaneous Kidney Biopsy • Ultrasound is used to locate the kidney • Spring-loaded needle used to extract kidney sample • Sample analysed by LM, IF and EM o IF: linear GBM staining with IgG in anti-GBM disease, mesangial staining with IgA in IgAN o EM: site of immune deposition, foot processes, fibrillary deposition