Figure 1.

Kidney and lung biopsy findings. Top panel shows kidney biopsy findings: (a) glomerulus shows membranoproliferative pattern of injury with markedly thickened glomerular basement membranes and a cellular crescent (hematoxylin and eosin, original magnification ×40), (b) bright staining for C3 in the mesangium and along capillary walls (original magnification ×40), and (c) osmiophilic dense intramembranous deposits (original magnification ×4000). Lower panel shows lung biopsy findings: (d) aveolar septae showing capillaritis with intra-alveolar hemorrhages (martius scarlet blue stain, original magnification ×40), (e) C3 staining along alveolar capillaries (original magnification ×20) with insert showing higher magnification of C3 staining of an alveolar capillary (original magnification ×60), and (f) sausage-shaped osmiophilic, continuous intramembranous electron-dense deposits in an alveolar capillary basement membrane (electron microscopy, original magnification ×4000). Arrows point to dense sausage-shaped osmiophilic deposits.