PMC5968240_01
Kidney biopsy findings. a Light microscopy shows a glomerulus with basement membrane double contours (arrows) and endocapillary hypercellularity. Periodic acid-Schiff stain; original magnification x400. b Immunofluorescence microscopy shows strong (4+), granular glomerular capillary wall and mesangial staining by lambda. Original magnification x400. c Immunofluorescence microscopy shows strong (4+), granular glomerular capillary wall and mesangial staining by IgG3. Original magnification x400. d Electron microscopy shows subepithelial (white arrow), subendothelial (blue arrow), and mesangial (red arrow) granular electron-dense deposits, some with a variegated appearance. Original magnification x1,500.
cnd-0008-0070-g01.jpg
PMC5968240_01_cnd-0008-0070-g01.jpg
F1
Under light microscopy, glomeruli had a membranoproliferative pattern with hyperlobulated glomeruli, diffuse endocapillary hypercellularity, diffuse glomerular basement membrane duplication, and mild mesangial matrix expansion with hypercellularity (Fig. 1a). IF demonstrated diffuse, global, chunky granular glomerular capillary wall and mesangial positive staining by IgG (4+ on a scale of 0-4), C1q (4+), C3 (4+), and lambda (4+) (Fig. 1b). IgA, IgM, and kappa were negative. IgG3 (4+) (Fig. 1c). IgG1, IgG2, and IgG4 were all negative. These deposits were granular with focally variegated texture (Fig. 1d).