Unusual Stroke-Like Presentation of Tumefactive Multiple Sclerosis in a 27-Year-Old Man

Tumefactive multiple sclerosis (TMS) is a rare subtype of multiple sclerosis with diverse clinical presentations, often leading to delays in diagnosis and treatment initiation. On investigation, it presents with a large (>2 cm) demyelinating mass-like lesion and can be accompanied by ring enhancement, perilesional edema, and mass effect. We report the case of a 27-year-old man who presented with right-sided weakness and numbness. He had a similar presentation one year ago without a definitive diagnosis. Computed tomography (CT) of the brain showed multiple bilateral hypodensities and vasogenic edema. Magnetic resonance imaging (MRI) of the brain revealed multifocal lesions with partial ring enhancement, which prompted further investigations. Laboratory studies and cerebrospinal fluid (CSF) analysis returned negative for infectious and autoimmune etiologies. Spinal MRI identified focal, non-enhancing lesions in the spinal cord, supporting a demyelinating process. The patient was diagnosed with TMS and received five days of IV methylprednisolone, resulting in significant improvement. This case highlights the importance of clinical suspicion of TMS, which can mimic other etiologies. It also shows the role of efficient history-taking in obviating the need for brain biopsy, which is usually done for similar cases exposing the patient to unwarranted adverse effects.