• Isolated central nervous system RDD requires attention for
differentiated diagnosis.
• RDD confused with IgG4-RD histopathologically but the disease
completely different.
• Emperipolesis evaluation with plasma cell density support the correct
diagnosis.
• It is confused with meningioma radiologically.
• In bilateral, dura-based lesions (mass-like), central nervous RDD can
be considered.
Rosai-Dorfman disease (RDD) is a benign histiocytosis with unknown
etiology. It generally occurs in cervical lymph nodes. Isolated central
nervous system (CNS) RDD is very rare in the literature. We reported a
case of no systemic involvement Rosai-Dorfmann which is rarely seen
and shows CNS involvement by mimicking meningioma. A 32-year-old
man presented with diplopia and a headache he has been experiencing
for the past two years. His neurological examination showed left facial
paresthesia, consistent with trigeminal nerve trace. Tendon reflexes were
increased at the right side and the right plantar reflex was extensor. Brain
magnetic resonance imaging demonstrated irregularly shaped, tumorlike
lesions in the bilateral cerebellopontin area that were compressing
pons. Rosai-Dorfman disease can be differentiated from IgG4 related
disease (IgG4-RD) by its characteristic features such as plasma cell density
and emperipolesis seen in its histopathology. Rosai-Dorfman disease can
be confused with other diseases radiologically and histopathologically,
especially the IgG4-RD, so be careful about differential diagnosis.
Keywords: Histiocytosis, IgG4 related disease, meningioma, Rosai-
Dorfman disease