Epimembranous glomerulonephritis (diagram)

Stage I: subepithelial depositions without reaction of the basal membrane

Stage II: spikes between subepithelial depositions

Stage III: integration of the subepithelial depositions into the basal membrane

Stage IV: increasing breakup of the integrated depositions and slow condensation of the basal membrane

Stage V: segmental sclerosis

Comment:
About 10% of kidney biopsies. Immune complex GN. 75% idiopathic. The rest caused by medications (penicillamine, gold, mercury, captopril), paraneoplastic, malaria, syphilis, hepatitis B, systemic diseases (systemic lupus erythematosus, chronic polyarthritis, sarcoidosis, renal vein thrombosis, renal transplant graft). Frequently insidious, episodic course. Initially isolated proteinuria, later progression to nephrotic syndrome. Late complications include hypertension and hematuria. Complement C3 and C4 are within normal limits.

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