Rosenthal fibers

Last edit by Alaric Steinmetz on

Rosenthal fibers are worm-like eosinophilic inclusions that can be detected histologically in astrocytic cells and were first described by the pathologist Werner Rosenthal in 1898.

Histopathology

Rosenthal fibers occur in reactively altered astrocytes. They are also a typical characteristic of pilocytic astrocytoma. Ultrastructurally, they are intermediate filaments with attached electron-dense material. Immunohistochemically, Rosenthal fibers are positive for alpha B-crystallin, ubiquitin, and (to varying degrees) for GFAP positive.

Illustration

Rosenthal fibers
Numerous eosinophilic (reddish colored) Rosenthal fibers in a section of a pilocytic astrocytoma. Hematoxylin-eosin staining.

Associated Conditions

Rosenthal fibers can be observed in pilocytic astrocytoma, Alexander disease, or astrocytosis[^1].