case_images: PMC5425770_01
case_images: Family pedigree. Our patient (Case 1) is a 40-year-old Japanese man. His 42-year-old brother (Case 2) had glomerulopathy. Their father (Case 3) had already died of nephrotic syndrome but did not undergo renal biopsy. Case 1 has 3 children who have no medical histories, and Case 2 has no offspring. There are no other family histories of kidney diseases. A black square stands for a patient with probable or definite fibrillary glomerulonephritis.
case_images: cnd-0007-0026-g01.jpg
case_images: PMC5425770_01_cnd-0007-0026-g01.jpg
case_images: F1
case_images: In the pedigree analysis (Fig. 1), Case 1's children had no medical history on routine school medical checkup.
case_images: Light microscopic findings of Case 1 and Case 2. Periodic acid methenamine (PAM) silver stain of Case 1 (PAM1) and Case 2 (PAM2) show mesangial expansion and glomerular capillary wall thickening with double contour formation localized to only a small part of the glomerulus.
case_images: cnd-0007-0026-g02.jpg
case_images: PMC5425770_01_cnd-0007-0026-g02.jpg
case_images: F2
case_images: All glomeruli showed mild mesangial expansion and segmental thickening of the glomerular capillary wall (Fig. 2). On light microscopy, 49 glomeruli were observed but no global or segmental sclerosis was observed, and there was diffuse mesangial matrix expansion, along with partial double contour of the glomerular basement membranes (Fig. 2).
case_images: Electron microscopic findings of Case 1. Electron microscopic images show electron-dense deposits, composed of randomly arranged nonbranching fibrils, measuring approximately 20 nm in external diameter (EM1), in the arteriolar basement membrane as well as mesangial lesion and glomerular basement membrane. EM2 shows fibrillary deposits (black arrows) in the arteriolar basement membrane. The asterisk and black square indicate a smooth muscle cell and vascular endothelium, respectively. Bars in EM1 (original magnification x40,000) and EM2 (original magnification x50,000) are 500 nm.
case_images: cnd-0007-0026-g03.jpg
case_images: PMC5425770_01_cnd-0007-0026-g03.jpg
case_images: F3
case_images: Electron microscopy revealed electron-dense deposits with randomly arranged nonbranching fibrils, measuring approximately 20 nm in diameter in the mesangial lesion and glomerular basement membranes (Fig. 3).