Type 2

Type II is characterized by:

• mesangial cell proliferation
• electon-dense, linear deposits intramembranous deposits that usually stain for C3 only
• C3 levels are reduced whilst C4 levels remain within the normal range - often associated with C3 nephritic factor, which causes alternative pathway complement activation (low C3 with normal C4)
• recurs in transplants
• light microscopy
  • enlarged glomeruli
  • lobulated due to mesangial cell proliferation
  • double contour basement membrane
• E.M.
  • characteristic dense ribbon like deposits in lamina densa
• immunofluorescence: C3 outlines glomerular B.M.

There is an association between mesangiocapillary glomerulonephritis and partial lipodystrophy; typically a female patient will have little subcutaneous adipose tissue above the waist.