# Neurosarcoidosis: When Altered Mental Status Is a Sign of Systemic Disease

## TL;DR

A 59-year-old woman with progressive cognitive decline was diagnosed with neurosarcoidosis using clinical and imaging findings, showing improvement with corticosteroid therapy.

## Contribution

This case emphasizes the importance of early diagnosis of neurosarcoidosis in subacute cognitive impairment presentations.

## Key findings

- Clinical and imaging findings supported a diagnosis of neurosarcoidosis without histological confirmation.
- Oral corticosteroid therapy led to significant clinical and imaging improvement in the patient.
- Neurosarcoidosis can present with subacute cognitive decline and should be considered in differential diagnosis.

## Abstract

Sarcoidosis is a systemic granulomatous disease of unknown etiology, characterized by a heterogeneous clinical course and the potential to affect any organ. Neurological involvement is rare and often mimics other nervous system disorders, with diagnosis based on the correlation of clinical, radiological, and histological findings, and biopsy of a suspected lesion serving as the definitive diagnostic method.

We report the case of a 59-year-old woman, previously independent, who presented with progressive cognitive decline over 4-5 weeks, culminating in the inability to perform basic activities. Based on clinical, laboratory, and imaging findings, including magnetic resonance imaging and FDG-PET, a diagnosis of neurosarcoidosis (NS) was established, and oral corticosteroid therapy was initiated, resulting in significant clinical and imaging improvement. Although histological confirmation was not obtained, the integration of clinical and imaging findings provided consistent support for the diagnosis.

This case highlights the importance of early recognition of NS, particularly in subacute presentations with cognitive impairment.