Transition from minimal change disease to focal segmental glomerulosclerosis related to occupational exposure: A case report

Figure 1 Light microscopy and electron microscopy of histological changes of renal biopsy 20 years ago. A: Periodic acid-silver methenamine (PASM), × 100. No obvious lesions in renal interstitium and arterioles; B: PASM, × 400. Vacuolar degeneration of glomerular capillary basement membrane (yellow arrow), renal tubular epithelial cells vacuoles and granular degeneration (white arrow); C and D: Extensive fusion of foot process of glomerular visceral epithelial cells (C: × 6000; D: × 12000, blue arrow).

Figure 2 Light microscopy and electron microscopy of histological changes of renal biopsy after 20 years. A: Masson, × 200. Multifocal and patchy atrophy of renal tubules, multifocal and patchy lymphocytic infiltration of renal interstitium with fibrosis (black arrow), and thickening of arterioles (white arrow); B: Periodic acid-silver methenamine, × 400. Mild segmental hyperplasia of glomerular mesangial cells and matrix, and segmental sclerosis (yellow arrow); C and D: Microvillous transformation of podocytes and extensive fusion of foot processes (C: × 6000, blue arrow; D: × 12000).