IntroductionMultiple sclerosis is an infrequent inflammatory disease of the central nervous system (CNS) that is distinguished by its assorted clinical and radiological presentations [1, 2]. Tumefactive demyelination, or tumefactive multiple sclerosis, stands apart as a distinctive entity within this spectrum. Demyelinating lesions in the central nervous system (CNS) are a sign of these diseases. These lesions can be big, measuring 2 cm or more in diameter, or small, measuring between 0.5 cm and 2 cm, but have the potential to cause mass effects. This unique feature may result in these lesions being initially misidentified as tumor-like space-occupying lesions; however, they typically exhibit a characteristic appearance on radiographic imaging and are clinically benign [3–5]. Tumefactive demyelination, which is distinct from multiple sclerosis, occurs at an estimated rate of about 1-2 per 1000 cases of MS, although some studies propose a higher incidence ranging from 1.4% to 8% [6–7]. However, tumefactive demyelinating lesions can occur concurrently with autoimmune diseases (e.g., Sjogren disease, lupus erythematosus, neuromyelitis optica), infectious diseases (e.g., HIV), malignancy (e.g., renal cell carcinoma), drug-related conditions (e.g., tacrolimus, fingolimod), and postinfectious conditions (e.g., acute disseminated encephalomyelitis, acute hemorrhage leukoencephalitis). Tumefactive demyelination can show up on its own at the start of a disease or as other diseases progress, but the pathophysiology of how it happens is not well understood. On magnetic resonance imaging (MRI) scans, these lesions can appear either as a single large lesion or several lesions exhibiting varying degrees of contrast enhancement. We present here a case study involving a thirty-year-old female who presented with a fever lasting three days followed by Wernicke’s aphasia without right-sided weakness and whose MRI findings were consistent with tumefactive brain demyelination.
