Figure 4.

Representative images of the post-treatment biopsy from patient C3GN1 illustrate strong glomerular staining for IgG and κ light chain, with negativity for λ light chain (column 1; ×600). By electron microscopy, the electron dense subendothelial deposits exhibited an unusual punctate highly electron dense powdery texture, resembling those seen in MIDD. This transformation in the appearance of the deposits post-therapy may represent binding of eculizumab to existing deposits. Original magnification, ×15,000 in A; 40,000 in B.