Electron microscopy of the thrombi ultrastructure shows lamellation
of the granular or vacuolated lipid material of which they are comprised and also demonstrates the presence of the lipid material between the glomerular basement membrane and the endothelial cells.
14,17) Likewise, ultrastructural abnormalities in the GBM may be less severe in autosomal recessive than in X-linked Alport syndrome, with a predominance of GBM thinning (resembling changes seen in TBMN or heterozygous carriers of X-linked Alport syndrome) rather than extensive splitting and lamellation
In contrast, in diabetic nephropathy the lamina densa of the glomerular basement membranes is classically thickened, and subepithelial lamellation
is often also present.
2] In contrast to Alport syndrome (AS), there are no widespread areas of thickening, lamellation
, or granular inclusions within the GBM,[3,4] although focal splitting has been described.
Occasionally, individual epidermoid cells possessed lamellar cytoplasmic keratinization or larger compact lamellations
of keratin (keratin pearls) [Figure 1]c.