Case Report: Paraneoplastic Hashimoto's Encephalopathy Associated With Lymphomatosis Cerebri With Periodic Synchronous Discharges Resembling Creutzfeldt–Jakob Disease

Hashimoto's encephalopathy (HE) is an autoimmune encephalopathy that presents with various clinical symptoms, including cognitive deterioration, convulsive seizures, and personality changes. HE is associated with thyroid autoimmunity; however, few cases have been reported to develop as paraneoplastic syndrome. Herein, we report the case of a 73-year-old woman with onset of rapidly progressive dementia. Brain magnetic resonance imaging showed diffuse T2 hyperintensity areas involving the bilateral cerebral white matter, right midbrain tegmental area, left cerebral peduncle, and right middle cerebellar peduncle without clear diffusion hyperintensities and gadolinium enhancement. Her neurological symptoms worsened rapidly, and she presented with the apallic syndrome. Electroencephalogram showed periodic synchronous discharge, suggestive of Creutzfeldt–Jakob disease. However, a brain biopsy revealed infiltration of atypical lymphoid cells expressing CD20, and the anti-NH2 terminal of the α-enolase antibody was detected, diagnosing the complication with lymphomatosis cerebri and HE. High-dose intravenous methylprednisolone therapy and oral prednisolone with whole cranial irradiation enabled her to have simple conversations and consume food orally; however, severe cognitive impairment persisted. Although HE is a rare complication of malignant lymphoma, clinicians should be aware that it could be strongly suspected if the clinical symptoms worsen in the absence of imaging changes.

Diffuse Infiltrative Non-mass-like Brain Parenchymal Lesions on MRI: Differentiating Lymphomatosis Cerebri from its Mimics

Objectives: Diffuse infiltrative “non-mass-like” parenchymal lesions on MRI brain are a known presentation of an aggressive condition called lymphomatosis cerebri (LC) but are often misdiagnosed due to its non-specific clinical and imaging findings. We aim to identify clues to differentiate lymphomatosis from its less aggressive mimics based on imaging features. Material and Methods: MRI brain studies showing diffuse infiltrative “non-mass-like” parenchymal lesions between January 2013 and March 2020 were retrospectively identified and read for lesion location, signal characteristics, and enhancement pattern by two radiologists. Additional findings on MRI spine and whole-body fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) were recorded wherever available. The clinical diagnosis, patient demographics, symptoms, laboratory and histopathology results, treatment details, and follow-up details were also noted. Results: Of the 67 patients, 28 (41.7%) were diagnosed with lymphomatosis. The remaining 39 (13.4%) patients were classified as non-lymphomas (infective, vasculitis, and inflammatory conditions). Diffusion restriction on MRI (20/67, P = 0.007) and increased regional activity on FDG PET-CT (12/31, P = 0.017) were the two imaging parameters found to significantly favor lymphomatosis over other conditions, whereas the presence of microhemorrhages on susceptibility-weighted imaging was significantly associated with vasculitis (P = 0.002). Rapid clinical or imaging deterioration on a short trial of steroids (P = 0.00) was the only relevant clinical factor to raise an early alarm of lymphomatosis. Positive serological markers and non-central nervous system systemic diseases were associated with non-lymphomatous diseases. Conclusion: LC and its less aggressive mimics can be differentiated on diffusion-weighted imaging-MRI and PET-CT when read in conjunction with rapid progression of clinical features, serological workup, and systemic evaluation.

Rapidly progressive dementia associated with leukoencephalopathy: A case report of lymphomatosis cerebri

Introduction Lymphomatosis cerebri is a rare form of primary central nervous system lymphoma characterized by an atypical clinical presentation and neuroimaging, with a poor short-term prognosis. Case Report A 51-year-old woman began with clinical manifestations characterized by rapidly progressing cognitive impairment associated with a behavioral disorder, myoclonus, and gait disturbance. The brain magnetic resonance image showed extensive signaling in the bilateral periventricular white matter. The 18F-FDG PET-CT showed severe dorsolateral neocortical hypometabolism in the absence of focal hypermetabolic lesion, a metabolic pattern indicative of cerebri lymphomatosis. A brain biopsy confirmed the diagnosis. The patient started chemotherapy achieving complete remission. Eighteen months after diagnosis, the patient had improved clinically and neuroimaging. Conclusion This is the first report in Peru of an entity that should be considered in rapidly progressive dementia and leukoencephalopathy cases. Timely diagnosis and appropriate chemotherapy management can increase patient survival.

LYMPHOMATOSIS CEREBRI RARE CASE SCENARIO

Central nervous system lymphoma is an infrequent variant of Lymphomatosis. It is an infrequent type of CNS lymphoma characterized by lymphoma cells diffusely inltrating the brain parenchyma without forming a mass or distorting the cerebral architecture. It is an unusual form of Non-Hodgkin lymphoma, majority being diffuse large B-cell lymphomas. I am presenting a case about 50-year woman with no vascular risk factor, who had a stealthy progressive dementia & right-side weakness Since July 2018.