Abstract | December 20, 2022
Tumefactive Multiple Sclerosis – A diagnosis dilemma
Learning Objectives
- Tumefactive MS can present as pseudo-stroke. The purpose of this report is to emphasize the need for timely and accurate diagnosis of MS to optimize treatment. By using disease-modifying agents, a reduction in the frequency and severity of relapses as well as a decrease in brain lesion development can occur. Unfortunately, the clinician often faces a nonspecific and/or atypical clinical presentation, particularly with the tumefactive form of this disease.
INTRODUCTION: Diagnosis of multiple sclerosis entails evidence of clinical neurological deficits and radiographic dissemination of disease in time. Multiple sclerosis(MS) plaques appear as well-demarcated, homogenous, small ovoid lesions on Magnetic resonace Imaging. Atypical radiographic features of MS lesions include size greater than 2 cm, mass effect, and edema. Tumefactive MS is a condition in which lesions radiographically mimic intra-cranial neoplasms, infarction, or infections. It is a rare form of multiple sclerosis, affecting 1-2 per1000 cases of MS, 3 cases per million per year in general population. We report a case of tumefactive MS who presented with focal neurological deficits and had challenging radiographic findings, posing a considerable diagnostic challenge to both the neurologist and neuroradiologist.
CASE: A 36-year-old white female with past medical history of hypertension, type 2 diabetes mellitus, and hyperlipidemia presented with progressive left sided weakness, slurred speech, dysphagia preceding with stumbling & numbness over left side of face, left arm and left leg over the period of 5 days.
On presentation, vitals were significant for tachycardia with heart rate 113/min and blood pressure 135/85mmhg. Examination revealed sensory deficits involving multiple neurologic territories, positive pronator drift in the left upper extremity and positive hoover sign pointing towards functional weakness. Left leg strength 4/5. Right side 5/5. Cardiopulmonary exam was normal.
She received loading dose of aspirin. Since patient was out of thrombolytic window, thrombolysis was not attempted. Magnetic resonance imaging Brain showed increased FLAIR and T2 signal in right para midline within pons extending to left cerebral peduncle, patchy nonspecific periventricular and sub cortical white matter changes, area of restricted diffusion in brainstem, suggesting subacute infarct initially started on treatment for stroke. Swallow evaluation showed deep laryngeal penetration and risk of aspiration and she was recommended mechanical soft diet with nectar thick liquids. Over the period of 3 days her status remained same and she was discharged to follow up with neurology.
Within 2 weeks she presented with progressively worsening of dysphagia, slurred speech, bladder incontinence, difficulty ambulating due to left sided weakness. Repeat MRI showed small punctate lacunar infarct in anterior belly of pons. Differentials at this time included mild microvascular ischemia and acute tumefactive demyelinating lesion of multiple sclerosis.
She underwent lumbar puncture and cerebrospinal fluid analysis which demonstrated elevated white cells of 57/CUMM, 100% mononuclear and 112mg/dl proteins. Clonal bands were negative. Investigation for autoimmune conditions were negative.
During the period of hospitalization, her left sided weakness progressed to hemiplegia with power 0/5 in the left upper extremity with brisk reflex, and decreased sensation. Cross adductor and positive Hoffman test noted in left lower extremity. She had progression to right sided weakness 3/5 with intact sensation on right. Worsening dysphagia resulted in placement of percutaneous endoscopic gastrostomy. At the time of discharge to rehabilitation center her strength on left side improved to 4/5. She received high dose steroids during hospitalization with plans to start Ocrelizumab in neurology clinic during follow up visit.
DISCUSSION: Our patient highlights the challenging interpretation of clinical and neuroradiological findings and the clinical dilemma in differentiating between acute stroke and acute MS. Acute MS can thus present as pseudo stroke. A natural course of tumefactive MS without treatment has been described as monophasic with a possible consequent conversion to typical relapsing-remitting MS. She did respond to high dose steroids. Therapeutic plasma exchange is another treatment modality along with IV Immunoglobulin.
