Lipid casts contain fat droplets (isolated or in groups), oval fat bodies or sometimes cholesterol crystals. Lipids enter the urine upon damage to the glomerular basal membrane. After filtration, they are taken up by tubular epithelial cells (leading to oval fat bodies) or embedded in a hyaline matrix, forming Lipid casts. The casts are usually round, highly refractive and variable in diameter. The amount of lipid droplets varies from sparse and scattered to so abundant as to completely mask the matrix. In rare cases, cholesterol plates protrude from the edges of the cast. Under polarized light, the lipids show the characteristic malteser cross pattern. Lipid casts are often accompanied by fat droplets or oval fat bodies in the urine sediment and are typical in patients with proteinuria in nephrotic range, but may also occur in patients without nephrotic syndrome.