Fatty casts are identified by the presence of refractile lipid droplets. The background matrix
of the cast may be hyaline or granular in nature. Often, they are seen in urines in which free
lipid droplets are present as well. Fatty casts are the most common type seen in cat urines.
Interpretation of the significance of "fatty" casts should be based on the character of the cast
matrix, rather than on the lipid content per se.
Pictured here is a fatty cast with a hyaline matrix. Also notice the free lipid droplets in the background. Such droplets are most commonly seen in feline urine. As an isolated finding, lipiduria is seldom of clinical significance. |
Last Updated: January 15, 1996