case_images: PMC10914425_01
case_images: Histopathologic and immunohistochemical analysis of kidney sections from patient and controls. (a, b) Representative glomeruli showing FSGS: (a) H&E (400X) and (b) PAS (400X). (c-e) Representative glomeruli showing cellular crescent formation: (c) H&E (400X), (d) PAS (400X), and (e) Toluidine Blue (400X). (f) Representative section of the renal cortex illustrating severe interstitial fibrosis, trichrome (100X). (g, h) Representative images showing diffuse podocyte foot process effacement, electron microscopy (3000X and 8000X). (i) Immunofluorescence confocal microscopy comparing localization of nephrin and synaptopodin in the patient's kidney to a control kidney. (j) Airyscan immunofluorescence microscopy comparing the patient's kidney to MCD and control kidneys.
case_images: CRIN2024-5121375.001.jpg
case_images: PMC10914425_01_CRIN2024-5121375.001.jpg
case_images: fig1
case_images: Light microscopy of H&E, PAS, Masson's trichrome, and toluidine blue stained sections showed focal segmental glomerulosclerosis (FSGS) and global glomerulosclerosis (5-10%), crescent formation, tubular microcystic changes, and severe interstitial fibrosis (Figures 1(a)-1(f)). Electron microscopy highlighted diffuse podocyte foot process effacement and normal glomerular basement membrane thickness without electron-dense deposits (Figures 1(g) and 1(h)). Relative to the control, the nonsclerotic and noncrescentic glomeruli in the patient's sample showed nephrin aggregation in the podocyte cell body instead of a linear distribution along the glomerular basement membrane (Figure 1(i)). Nephrin colocalized with synaptopodin in a healthy control glomerulus, which was not observed in the patient's tissue (Figure 1(i)). Using Airyscan immunofluorescence microscopy, the nonsclerotic and noncrescentic glomeruli in the patient's sample showed strong nephrin staining in the podocyte cell body that was not present in the MCD or control kidney samples, indicating that the nephrin mislocalization is not simply a feature of diffuse podocyte foot process effacement as seen in MCD (Figure 1(j)).