Sarcoidosis is a multisystem disease of unknown etiology that may be a constellation of diseases rather than a single entity. Neurologic involvement is seen in only 5-10% of cases and of those with neurosarcoidosis only 10-17% develop systemic disease. Diagnosis can be challenging, and treatments vary from institution and provider.
A 50-year-old male underwent cervical laminectomy and posterior spinal fusion for cervical spondylotic myelopathy diagnosed after MRI had demonstrated cervical spinal canal stenosis with prominent cord enhancement. Prior to surgery he had mild weakness preceded by progressive lower extremity sensory changes, saddle anesthesias, and incontinence. One month following surgery he was wheelchair bound and had developed symptoms in his upper extremities. Neurology was consulted and repeat MRI demonstrated increased cord signal from the obex of the medulla through T7. A review of presurgical MRIs found a trident sign on axial cuts suggestive of neurosarcoidosis. Serum studies found an elevated IL-2 receptor alpha and angiotensin converting enzyme (ACE). Extensive serum and CSF testing was used to evaluate other possible causes. With the diagnosis of possible neurosarcoidosis he received high dose steroids. Early pulmonary lymph node biopsy was without evidence of granulomas but repeat biopsy weeks later revealed noncaseating granulomas changing his diagnosis to probable neurosarcoidosis. Clinical improvement was seen with steroids and infliximab. At 6-month imaging significant improvement was seen but there was continued enhancement which extended his treatment course.
This case highlights the importance of unique and sometimes subtle radiographic features in sarcoidosis, which can often be overlooked in the setting of severe spondylotic disease that may produce confounding imaging findings. Maintaining a high clinical index of suspicion for neurosarcoid is paramount when the clinical course and spinal imaging are disproportionate to and not entirely explained by spondylotic myelopathy.