Fig. 1.

Light microscopy and immunofluorescence findings (a): The segmental sclerosis lesion at the perihilar area is indicated by an arrow. A red-coloured podocyte (ReCPo) is surrounded by a square, magnified at the top right (AZAN stain). (b): The ReCPo is indicated by an arrow (AZAN stain). (c): GSECs in the distal tubules are indicated by arrows (AZAN stain). One GSEC is magnified at the lower left. (d): Staining of COX IV emphasizes tubular cells, including many mitochondria, which correspond to GSECs. (e): In the afferent arteriole that connects to the glomerulus of (a), the sizes of the vascular smooth muscle cells are irregular, and their arrangement is disorganized, similar to those seen in older patients (PAM-HE stain). (f): Age-inappropriately disarranged and irregularly sized vascular smooth muscle cells (AiDIVs) are observed in an interlobular artery (PAM-HE stain). (g): IgM deposits are detected in glomeruli. (h): IgG deposits are detected in glomeruli. (i): C1q deposits are detected in glomeruli.