A Dorsal Epidural Herniated Disc Fragment Initially Presenting as Guillain-Barré Syndrome.

Guillain-Barré syndrome (GBS) is a rare autoimmune disorder that presents with neurological symptoms that can mimic other conditions. This mimicry can hide other important neurological diagnoses. Here, we present a rare case of thoracic myelopathy secondary to a sequestered dorsal epidural herniated disc fragment that initially presented with the classic findings of GBS. A 58-year-old female presented with progressing bilateral lower extremity weakness, paresthesias, and absent bilateral lower extremity deep tendon reflexes. Lumbar magnetic resonance imaging (MRI) findings were disproportionate to presentation, and lumbar puncture fluid analysis revealed clear, colorless fluid with albuminocytological dissociation. The patient was diagnosed with GBS and treated with a short course of intravenous steroids followed by intravenous immunoglobulin. The patient later developed new-onset ulnar distribution paresthesias, lower extremity spasticity, constipation, and urinary retention that caused a decline in functional progress. Further investigation prompted evaluation with cervical and thoracic MRIs, which revealed a left dorsal epidural lesion at the T9-T10 level causing severe cord compression. The patient was definitively treated with a T9-T10 laminectomy and excision of the offending lesion. Pathology revealed collagenous tissue with fibroblastic proliferation, consistent with a sequestered fragment of the herniated intervertebral disc. The patient was further treated with both acute and subacute rehabilitation. She was eventually discharged home and was able to ambulate independently with a walker. Dependency on positive albuminocytological dissociation in cases of potential GBS can lead to errors in diagnostic accuracy and delay appropriate treatment. Clinicians should remain mindful that GBS is a diagnosis of exclusion and MRI of the entire spine should be considered when the diagnosis of GBS is uncertain.