Figure 3
a. Positive mesangial IgA staining in immunofluorescence (high power field). b. Light microscopy - glomerulus with remarkably enlarged podocytes with many vacuoles in their cytoplasm. Swollen lacy cytoplasm of podocytes is indicative of FD (Jones methenamine silver stain; high power field). Please note, diagnostic IgA deposits in mesangium were shown in immunofluorescence. c. Semithin section stained with toluidin blue showed characteristic “blue inclusions” mainly in podocytes. These features together with large podocytes with vacuolated cytoplasm in light microscopy represent a key to the morphological diagnosis of FD.