Metabotropic glutamate receptor 5-related autoimmune encephalitis with reversible splenial lesion syndrome following SARS-CoV-2 vaccination.

RATIONALE: Metabotropic glutamate receptor 5 (mGluR5)-related autoimmune encephalitis (AE) has been rarely reported; however, there are no reports on mGluR5-related AE with reversible splenial lesion syndrome following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). PATIENT CONCERNS: A 29-year-old man was admitted with a history of headache and fever for 9 days and 6 days, respectively. DIAGNOSIS: He was initially diagnosed with an intracranial infection, however the final diagnosis was corrected as anti-mGluR5-related AE with reversible splenial lesion syndrome. INTERVENTIONS: He had received an inactivated SARS-CoV-2 vaccine 3 weeks prior to the examination and was initially diagnosed with an intracranial infection. Physical examination revealed bilateral horizontal nystagmus, ataxia, and neck rigidity. Antiinfective therapy was minimally helpful. An analysis of the cerebrospinal fluid did not reveal pathogens for sequencing. Magnetic resonance imaging displayed abnormal signals in the splenium of the corpus callosum. OUTCOMES: We identified mGluR5 antibodies in the cerebrospinal fluid and serum. Subsequently, intravenous methylprednisolone pulse and gamma-globulin pulse therapies were administered, which substantially improved the symptoms. Follow-up did not reveal abnormal neurological symptoms, and the lesion in the corpus callosum had resolved. LESSONS: AE with mGluR5 antibodies could arise from SARS-CoV-2 vaccination, which warrants the awareness of healthcare workers. Reversible splenial lesion syndrome may accompany mGluR5-related AE and mimic intracranial infection. Thus, early treatment can prevent serious residual signs and symptoms.

Terminal ileitis and cytotoxic lesion of corpus callosum as the presenting features of Multisystem inflammatory syndrome in children (MIS-C): a case report.

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) is a post-viral inflammatory vasculopathy characterized by persistent fever, multiorgan dysfunction, significant laboratory markers of inflammation, lack of an alternative diagnosis, and prior SARS-CoV-2 infection or exposure in children and adolescents. The most common early symptoms include a prolonged fever, as well as dermatologic, mucocutaneous, and gastrointestinal symptoms such abdominal pain, vomiting, and diarrhea. CASE PRESENTATION: We present a pediatric patient with multisystem inflammatory syndrome with the development of abdominal pain and seizure who was found to have a circumferential wall thickening of the terminal ileum and ileocecal junction in abdominal CT scan. The brain MRI of the patient showed cytotoxic lesions of the corpus callosum (CLOCC) which had hypersignal intensity with a few diffusion restrictions in the splenium of the corpus callosum. CONCLUSION: This case is being reported to raise awareness of MIS-C presenting characteristics. Given the rising number of MIS-C patients and a lack of understanding regarding early diagnostic clinical characteristics and therapy, further research into clinical presentations, treatment, and outcomes is urgently needed.

Cytotoxic lesions of the corpus callosum after COVID-19 vaccination.

A 23-year-old previously healthy man (Patient 1) and a 33-year-old woman with a past history of depression (Patient 2) developed neurological symptoms approximately 1 week after receipt of the first COVID-19 mRNA vaccination and deteriorated over the next week. Patient 1 reported nausea, headache, a high fever, and retrograde amnesia. Patient 2 reported visual disturbance, headache, dysarthria, a left forearm tremor, dysesthesia of the mouth and distal limbs, and visual agnosia. PCR test results for SARS-CoV-2 were negative. Complete blood cell count, biochemistry, and antibody test and cerebrospinal fluid test findings were unremarkable. Diffusion-weighted and fluid-attenuated inversion recovery MRI of the brain showed a high signal intensity lesion at the midline of the splenium of the corpus callosum compatible with cytotoxic lesions of the corpus callosum (CLOCCs). High-dose intravenous methylprednisolone improved their symptoms and imaging findings. CLOCCs should be considered in patients with neurological manifestation after COVID-19 vaccination.

"Reversible cytotoxic lesion of the corpus callosum following SARS-CoV-2 mRNA vaccine administration: a finding to be aware of".

Cytotoxic lesions of the corpus callosum (CLOCCs) are a clinical-radiological spectrum of disorders secondary to several etiopathogeneses. Cytotoxic lesions of the corpus callosum are typically associated with mild clinical symptoms including fever, headache, confusion, and altered mental status. We present a case of a 51-year-old Caucasian woman who developed a reversible lesion of the splenium of the corpus callosum associated with small round-shaped white matter hyperintensities after the first dose of SARS-CoV-2 mRNA vaccine. Magnetic resonance imaging is fundamental for diagnosis and no treatment is generally required.

Tumefactive Demyelinating Brain Lesion Developing after Administration of Adenovector-Based COVID-19 Vaccine: A Case Report.

Background: Postmarketing surveillance of COVID-19 vaccination reveals that the COVID-19 vaccine administration is associated with several rare but serious neurological complications. Case Report: We report a case of new-onset tumefactive demyelinating brain lesion that developed after administration of an adenovector-based COVID-19 vaccine. A middle-aged female presented with recent right hemiparesis, which was noticed 2 days after she received the first dose of the vaccine. Magnetic resonance imaging (MRI) revealed a large subcortical T2/FLAIR hyperintensities involving corpus callosum as well. The patient responded to oral methylprednisolone. At 4 weeks, a follow-up MRI revealed a reduction in size of the lesion. Conclusion: To conclude, adenovector-based COVID-19 vaccination may be associated with a tumefactive demyelinating lesion.

Cytotoxic lesions of the corpus callosum in children: Etiology, clinical and radiological features, and prognosis.

OBJECTIVES: Cytotoxic lesions of the corpus callosum (CLOCCs) are secondary lesions associated with entities like infection manifested by restricted diffusion on diffusion-weighted cranial magnetic resonance imaging. Our objectives are to evaluate the clinic-radiological spectrum of pediatric patients with cytotoxic lesions of the corpus callosum (CC). METHODS: Children (0-18 years) admitted between February 2017 and May 2020 with splenial lesions showing diffusion restriction on MRI, either isolated or within involvement of other parts of the brain, were included retrospectively. The primary lesions of the CC (e.g. acute disseminated encephalomyelitis, acute ischemic infarction, and glioblastoma multiforme) were excluded. CLOCCs were divided into infection-associated, metabolic disorder-associated, and trauma-associated lesions, as well as CLOCCs involving other entities. Data were collected from the medical databases. RESULTS: Forty-one patients were determined to have CLOCCs. Twenty-five (61%) were infection-associated, nine (22%) were trauma-associated, and three (7%) were metabolic disorder-associated cases, including 2 inherited disorders of metabolism. There were four (10%) patients with other entities, three with epilepsy, and one had an apparent life-threatening event. Six patients had a known etiology among the infection-associated group; one had multisystem inflammatory syndrome caused by COVID-19 and one had been infected by COVID-19 without any complications. All the infection-associated patients with isolated splenial lesions recovered totally, although six patients required intensive care hospitalization. Four trauma-associated patients had sequela lesions. CONCLUSIONS: CLOCCs are associated with a spectrum of diseases, including the new coronavirus, COVID-19 infection. Infection-associated CLOCCs has the best prognosis, although severe cases may occur. Sequelae are possible based on the etiology.

A 23-Year-Old Man with SARS-CoV-2 Infection Who Presented with Auditory Hallucinations and Imaging Findings of Cytotoxic Lesions of the Corpus Callosum (CLOCC).

BACKGROUND Cytotoxic lesions of the corpus callosum (CLOCC) is a rare clinical and radiological syndrome that has been associated with various infectious etiologies. CLOCC are among the recently described neurological associations with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with coronavirus disease 2019 (COVID-19). We report a case of CLOCC in a man with SARS-CoV-2 infection who presented with auditory hallucinations and rapidly developed systemic inflammatory response syndrome (SIRS). CASE REPORT A 23-year-old man with no past medical and psychiatric history presented with auditory hallucinations, restlessness, and suicidal ideations. A nasopharyngeal swab specimen tested using real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay was positive for SARS-CoV-2. A brain MRI revealed an isolated oval-shaped lesion in the splenium of the corpus callosum, with hyperintense signal on diffusion-weighted imaging (DWI) and hypointense on apparent diffusion coefficient (ADC) maps, suggestive of CLOCC. After a dramatic hospital course associated with multiple organ dysfunction syndrome (MODS) and severe intra-abdominal and cerebral bleeding, he developed cardiac arrest and died on hospital day 15. CONCLUSIONS This case highlights the need for increased vigilance for the atypical manifestations of SARS-CoV-2 infection. In addition, it suggests that CLOCC can be considered as a differential diagnosis by clinicians in patients with SARS-CoV-2 infection who present with unexplained neurological and neuropsychiatric symptoms, leading to poor outcome.

Cerebral microhaemorrhage in COVID-19: a critical illness related phenomenon?

BACKGROUND: Cerebral microhaemorrhages are increasingly being recognised as a complication of COVID-19. This observational retrospective study aims to further investigate the potential pathophysiology through assessing the pattern of microhaemorrhage and clinical characteristics of patients with COVID-19 and microhaemorrhage. By comparing with similar patterns of microhaemorrhage in other non-COVID-19 disease, this study aims to propose possible common pathogenic mechanisms. METHODS: A retrospective observational case series was performed identifying all patients with COVID-19 complicated by cerebral microhaemorrhage on MRI. The distribution and number of microhaemorrhages were recorded using the microbleed anatomical scale, and patients' baseline characteristics and salient test results were also recorded. RESULTS: Cerebral microhaemorrhages were noted to have a predilection for the corpus callosum, the juxtacortical white matter and brainstem. All patients had a preceding period of critical illness with respiratory failure and severe hypoxia necessitating intubation and mechanical ventilation. DISCUSSION: This study demonstrates a pattern of cerebral microhaemorrhage that is similar to the pattern reported in patients with non-COVID-19 related critical illness and other causes of severe hypoxia. This raises questions regarding whether microhaemorrhage occurs from endothelial dysfunction due the direct effect of SARS-CoV-2 infection or from the secondary effects of critical illness and hypoxia.

Reversible splenial lesion syndrome associated with SARS-CoV-2 infection in two children.

BACKGROUND: Reversible splenial lesion syndrome (RESLES) is characterized by a temporary lesion in the splenium of the corpus callosum, emerging related to encephalitis, seizures, antiepileptic drug withdrawal, or metabolic disturbances. Among RESLES, mild encephalitis/encephalopathy with reversible splenial lesion (MERS) has been defined as a distinct clinicoradiologic syndrome associated with viral infections. CASE PRESENTATION: We report two children with multisystem inflammatory syndrome-children related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who developed RESLES during the disease course. Encephalopathy was the main central nervous system symptom. Both of the children showed a rapid recovery, and brain magnetic resonance imaging revealed complete resolution of the splenial lesion within 1 week. CONCLUSION: The complete resolution of the splenial lesion and rapid recovery from encephalopathy in RESLES associated with SARS CoV-2 were similar to observed in MERS.

COVID-19-Associated Cytotoxic Lesions of the Corpus Callosum.

There are very limited published data on the neurologic complications associated with coronavirus disease 2019 (COVID-19) in the pediatric population. Here we present the first 2 pediatric cases of presumed COVID-19 related cytotoxic lesions of the corpus callosum. Similar to reports in adults, these cases suggest that the COVID-19 infection in children may rarely mediate a hyperinflammatory response that can cause CNS pathology. As the pandemic continues further, the presentation of cytotoxic lesions of the corpus callosum should prompt radiologists to consider COVID-19, among other known causes.