Systemic Sarcoidosis With Neurosarcoidosis and Obstructive Hydrocephalus: A Radiologic-Pathologic Case Report.

Sarcoidosis is a systemic granulomatous disease characterized by non-caseating granulomas, most commonly affecting the lungs and intrathoracic lymph nodes. Central nervous system involvement (neurosarcoidosis) is rare but associated with significant morbidity and mortality, particularly in advanced systemic disease. We report a fatal case of a 43-year-old man with long-standing pulmonary sarcoidosis who developed progressive neurosarcoidosis complicated by obstructive hydrocephalus and subsequent ventriculoperitoneal shunt infection. High-resolution computed tomography demonstrated advanced perilymphatic and peribronchovascular fibrosis with symmetric mediastinal lymphadenopathy, consistent with fibrotic pulmonary sarcoidosis (Scadding stage IV). Contrast-enhanced brain magnetic resonance imaging revealed a large, intensely enhancing mass-like lesion centered in the atrium of the right lateral ventricle, with extension into the posterior and temporal horns, causing near-complete obliteration of the ventricular lumen and secondary obstructive hydrocephalus. Autopsy showed extensive fibrotic and granulomatous remodeling of the lungs with non-caseating granulomas. Histological examination of tissue obtained from the central nervous system lesion demonstrated non-necrotizing granulomatous inflammation, supporting central nervous system involvement; however, the precise anatomical origin of the intraventricular lesion was not established microscopically. This case highlights a rare and fatal presentation of sarcoidosis with combined fibrotic pulmonary involvement and neurosarcoidosis. Mechanical obstruction by the mass-like intraventricular lesion played the principal role in the development of hydrocephalus. Radiologic-pathologic correlation provided important insights into the underlying disease mechanisms.