C40-21 When Sarcoidosis Hits the Spine: Cauda Equina Syndrome as a Rare Presentation

Abstract Introduction Sarcoidosis is a systemic granulomatous disorder with a wide spectrum of clinical manifestations, ranging from asymptomatic disease to progressive, multisystem involvement. Neurological manifestations occur in 3-5% of cases [1]. Although bilateral hilar lymphadenopathy is considered a “highly probable” finding per American Thoracic Society (ATS) guidelines, variability in organ involvement and presentation contributes to diagnostic uncertainty, delayed recognition, and an underappreciated global health burden [2]. We present a case of neurosarcoidosis with intrapulmonary lymphadenopathy and cauda equina involvement. Case Description A 33-year-old African American male with hypertension and alcohol use disorder presented with progressive lower back pain, bilateral lower extremity weakness, and numbness progressing for one year following a ground-level fall. Three months before admission, he developed bowel and bladder incontinence. Magnetic resonance imaging (MRI) of the thoracic and lumbar spine revealed extensive mediastinal and hilar lymphadenopathy with multifocal right lung nodules, severe left foraminal stenosis at L5-S1, and scattered enhancement of the cauda equina nerve roots, raising suspicion for neurosarcoidosis. Erythrocyte sedimentation rate was elevated at 22 mm/hr. Cerebrospinal fluid (CSF) demonstrated 33 nucleated cells, with 94% lymphocytes, elevated protein at 219 mg/dL, and negative Gram stain. Infectious and autoimmune testing - including syphilis and complement levels C3 and C4 - were negative. Flow cytometry excluded hematolymphoid malignancy, and both serum and CSF angiotensin-converting enzyme (ACE) and lysozyme were within normal limits. Bronchoscopy with fine-needle aspiration of intrathoracic lymph nodes (stations 1L and 7) revealed scattered noncaseating granulomas with negative acid-fast bacilli and Periodic Acid-Schiff (PAS) stains, confirming sarcoidosis. The patient received 1 gram intravenous methylprednisolone for five days, followed by a 12-week oral prednisone taper. With physical therapy, he regained partial lower extremity strength and ambulated with a walker at discharge. Discussion This case highlights the diagnostic complexity of sarcoidosis, particularly when neurological deficits precede other manifestations. The patient had multiple prior emergency department visits for similar complaints with incomplete evaluation. Cranial neuropathies, the most common neurological manifestation, occur in approximately 50% of neurosarcoidosis cases, with neurological symptoms often driving initial evaluation [1,3-5]. Diagnosis relies heavily on histologic confirmation of noncaseating granulomas, often obtained from extra-neural tissue, such as via bronchoscopy. As in this case, treatment response also provides diagnostic utility. Greater recognition of neurosarcoidosis and inclusion of disease-specific diagnostic guidance within ATS recommendations may improve early identification and outcomes [2]. Clinicians should consider neurosarcoidosis within their differential when evaluating patients with cauda equina syndrome of unclear etiology. This abstract is funded by: None