Rapid Progression of Angioimmunoblastic T cell Lymphoma following BNT162b2 mRNA Vaccine Booster Shot. A Case Report (preprint)

Since nucleoside-modified mRNA vaccines strongly activate T follicular helper cells, it is important to explore the possible impact of approved SARS-CoV-2 mRNA vaccines on neoplasms affecting this cell type. Herein, we report and discuss unexpected rapid progression of lymphomatous lesions after administration of a BNT162b2 mRNA vaccine booster in a man recently diagnosed with AITL.

Structural and metabolic brain abnormalities in COVID-19 patients with sudden loss of smell (preprint)

ObjectivesSudden loss of smell is a very common symptom of coronavirus disease 19 (COVID-19). This study characterizes the structural and metabolic cerebral correlates of dysosmia in patients with COVID-19. MethodsStructural brain magnetic resonance imaging (MRI) and positron emission tomography with [18F]-fluorodeoxyglucose (FDG-PET) were prospectively acquired simultaneously on a hybrid PET-MR in twelve patients (2 males, 10 females, mean age: 42.6 years, age range: 23-60 years) with sudden dysosmia and positive detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on nasopharyngeal swab specimens. FDG-PET data were analysed using a voxel-based approach and compared with that of a group of healthy subjects. ResultsBilateral blocking of the olfactory cleft was observed in six patients, while subtle olfactory bulb asymmetry was found in three patients. No MRI signal abnormality downstream of the olfactory tract was observed. Heterogeneous (decrease or increase) glucose metabolism abnormalities were observed in core olfactory and high-order neocortical areas. A modulation of regional cerebral glucose metabolism by the severity and the duration of COVID-19-related dysosmia was disclosed using correlation analyses. ConclusionsThis PET-MR study shows that sudden loss of smell in COVID-19 is not related to central involvement due to SARS-CoV-2 neuroinvasiveness. Loss of smell is associated with heterogeneous cerebral metabolic changes in core olfactory and high-order cortical areas likely related to combined processes of deafferentation and active functional reorganisation secondary to the lack of olfactory stimulation.

Early postmortem brain MRI findings in COVID-19 non-survivors (preprint)

ImportanceThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is considered to have potential neuro-invasiveness that might lead to acute brain disorders or contribute to respiratory distress in patients with coronavirus disease 2019 (COVID-19). Brain magnetic resonance imaging (MRI) data in COVID-19 patients are scarce due to difficulties to obtain such examination in infected unstable patients during the COVID-19 outbreak. ObjectiveTo investigate the occurrence of structural brain abnormalities in non-survivors of COVID-19 in a virtopsy framework. DesignProspective, case series study with postmortem brain MRI obtained early (<24h) after death. SettingMonocentric study. ParticipantsFrom 31/03/2020 to 24/04/2020, consecutive decedents who fulfilled the following inclusion criteria were included: death <24 hours, SARS-CoV-2 detection on nasopharyngeal swab specimen, chest computerized tomographic (CT) scan suggestive of COVID-19, absence of known focal brain lesion, and MRI compatibility. Main Outcome(s) andMeasure(s)Signs of acute brain injury and MRI signal abnormalities along the olfactory tract and brainstem were searched independently by 3 neuroradiologists, then reviewed with neurologists and clinicians. ResultsAmong the 62 patients who died from COVID-19 during the inclusion period, 19 decedents fulfilled inclusion criteria. Subcortical micro- and macro-bleeds (2 decedents), cortico-subcortical edematous changes evocative of posterior reversible encephalopathy syndrome (PRES, one decedent), and nonspecific deep white matter changes (one decedent) were observed. Asymmetric olfactory bulbs were found in 4 other decedents without downstream olfactory tract abnormalities. No brainstem MRI signal abnormality. Conclusions and RelevancePostmortem brain MRI demonstrates hemorrhagic and PRES-related brain lesions in non-survivors of COVID-19 that might be triggered by the virus-induced endothelial disturbances. SARS-CoV-2-related olfactory impairment seems to be limited to olfactory bulbs. The absence of brainstem MRI abnormalities does not support a brain-related contribution to respiratory distress in COVID-19. Key PointsO_ST_ABSQuestionC_ST_ABSIs there common brain MRI abnormalities patterns in non-survivors of coronavirus disease 2019 ? FindingsIn a case series of 19 non-survivors of severe COVID-19 disease, early postmortem brain MRI demonstrated patterns evocative of intracranial vasculopathy in 4 decedents: subcortical micro- and macro-bleeds (2 decedents), cortico-subcortical edematous changes evocative of posterior reversible encephalopathy syndrome (PRES, one decedent), and nonspecific deep white matter changes (one decedent). Asymmetric olfactory bulbs were found in 4 other decedents but without downstream olfactory tract abnormalities. MeaningPostmortem brain MRI demonstrates hemorrhagic and PRES-related brain lesions in non-survivors of COVID-19 that might be triggered by virus-induced endothelial disturbances.