Rosenthal fibers are worm-shaped eosinophilic inclusions that can be detected histologically in astrocytic cells and were first described in 1898 by the pathologist Werner Rosenthal.
Histopathology
Rosenthal fibers occur in reactive astrocytes. They are also a characteristic feature of pilocytic astrocytoma. Ultrastructurally, they consist of intermediate filaments with electron-dense material attached. Immunohistochemically, Rosenthal fibers are positive for alpha B-crystallin, ubiquitin, and (to varying degrees) GFAP.
Figure
Associated diseases
Rosenthal fibers may be observed in pilocytic astrocytomas, Alexander disease, or astrocytosis[^1].