Epithelial casts

Clinical relevance

These casts belong to the category of cellular casts. They are found in many kidney disturbances, but especially in the presence of nephrotic syndrome. They are also observed in cases of cytostatic treatment of a neoplastic disease, as many cytostatic drugs are nephrotoxic and cause significant tubular damage. They are also frequent in viral hepatitis or cytomegalovirus infection. In kidney transplantation, a rejection reaction can be revealed by the appearance of epithelial casts.

Origin

Epithelial casts originate from the tubular epithelium. In case of tubular disease, damaged tubular epithelial cells are shed into the urine and incorporated into the mucoprotein matrix.

Identification

Epithelial casts are recognizable by their high refractive index and their cellular composition. Renal epithelial cells have a large nucleus and cytoplasmic granules. The cells of the cast can be intact or display varying degrees of degeneration. During the process of decomposition, fat may be incorporated into the epithelial cells.

Two examples of epithelial casts