Tumefactive multiple sclerosis comprises a rare subset of multiple sclerosis that often poses a diagnostic challenge to physicians. It is unique in its presentation as a solitary lesion, usually larger than 2 cm, with surrounding vasogenic edema, commonly mimicking a primary intracranial malignancy. We present a case of a 25-year-old female with no significant past medical history who presented to our institution with homonymous superior quadrantanopia. During her admission, she underwent a magnetic resonance imaging (MRI) of the brain, which revealed a large lesion in the left temporal area surrounded by marked edema. A thorough workup revealed a diagnosis of tumefactive multiple sclerosis. Subsequently, she was initiated on intravenous immunoglobulin rather than stress dose steroids, given the concern for a superimposed infection. Interestingly, the patient had a paradoxical progression of her symptoms as well as expansion of the vasogenic edema on a repeat MRI. In our case, we highlight the key differences in tumefactive multiple sclerosis diagnosis and management.

INTRODUCTION:Extracorporeal membrane oxygenation (ECMO) provides life-saving support in severe coronavirus disease-19 infections resulting in acute hypoxemic respiratory failure refractory to conventional medication support. We examine the trend of inflammatory markers, including D-dimers, in COVID-19 patients requiring extracorporeal support. METHODS:We retrospectively analyzed 29 patients with COVID-19 infection requiring veno-venous (VV) ECMO. Demographics, pre-ECMO characteristics, complications, and blood product requirements were compared between patients with D-dimer levels < 3,000 versus >3,000 ng/ mL using independent two-sample Student's t-tests for continuous variables and chi-squared test for categorical variables. Inflammatory marker levels for patients before and after circuit exchanges were compared using paired samples t-tests. RESULTS:COVID-19 patients with pre-cannulation D-dimer levels >3,000 ng/mL had a significantly shorter time from admission to cannulation (4.78 vs 8.44 days, p=0.049) compared to those with D-dimer < 3,000 ng/mL. Furthermore, patients with D-dimer >3,000 ng/mL had a trend of lower pH (7.24 vs 7.33), higher pCO2 (61.33 vs 50.69), and higher VIS scores (7.23 vs 3.97) at time of cannulation, however these were not statistically significant. This cohort of patients also required longer duration of ECMO support (51.44 vs 31.25 days). 13 patients required at least one ECMO-circuit exchange and 16 patients did not require any exchanges. There was a consistent drop in D-dimer values after every circuit exchange, which was not observed in any of the other examined inflammatory markers including Ferritin, LDH, or CRP.CONCLUSIONS: Elevated D-dimer levels (>3,000 ng/mL) likely reflect increased disease severity in COVID-19, and predict a longer ECMO course. Once on ECMO, however, the D-Dimer level consistently decreased with circuit exchange and may reflect thrombus within the oxygenator rather than disease severity.