Fig. 1

Representative light and electron microscopy images of the first and second biopsies. a Mesangial proliferation with segmental sclerosis (arrowheads; periodic acid-Schiff staining; original magnification, 400×). b Double-contour formation (arrows; periodic acid methenamine silver staining; original magnification, 400×) (c) Subendothelial (asterisks) and paramesangial (arrowheads) deposits (electron micrograph; original magnification, 4000×). (a–c) Images from the first biopsy at age 5. d Irregularities of the GBM (asterisks) with mesangial interposition (asterisks; electron micrograph; original magnification, 8000×). d Image from the second biopsy at age 6. GBM: glomerular basement membrane