American Urological Association - Normal Transitional Cells
Normal Transitional Cells
Superficial transitional cells ("umbrella cells")
- Form the majority of cells in specimens.
- Vary greatly in size and shape, but generally are flat, large, polygonal cells (image A).
- Abundant thin (transparent) cytoplasm, +/- vacuolation.
- Nuclear chromatin is dusty or finely granular (salt and pepper) without nucleoli.
- Multinucleation (>2, <50) may be seen as a reactive change, along with small red nucleoli.
Deep transitional cells
- Same as superficial cells, except smaller with denser blue cytoplasm (image B).
- Includes intermediate and basal cells, which are cytologically similar.
- Increased numbers seen with: instrumentation/catheterization; calculi; and inflammatory/neoplastic conditions.