Cerebellar progressive multifocal leucoencephalopathy identified by the shrimp sign.

Progressive multifocal leucoencephalopathy (PML) is a demyelinating disease caused by the John Cunningham (JC) virus, which may get reactivated under certain immunosuppressive states such as AIDS, immunomodulatory therapy and haematological malignancies. PML has been reported rarely even in immunocompetent individuals where no immunodeficiency was present. PML characteristically involves periventricular and juxtacortical white matter. Isolated cerebellar or brainstem PML may be seen rarely. We present a case of a man in his 70s who presented with rapidly progressive cerebellar ataxia, ptosis and bipyramidal signs. Investigations excluded a direct viral cerebellar infection, acute disseminated encephalomyelitis, paraneoplastic cerebellar degeneration or any structural cerebellar lesion. MRI PET study revealed the classical shrimp sign which raised the possibility of cerebellar PML, and the same was confirmed by a positive JC virus PCR in the cerebrospinal fluid. Our patient had no known immune-compromising state, but further workup revealed a low CD4 count suggestive of idiopathic CD4 lymphopenia. The case illustrates the importance of the shrimp sign on MRI, the possibility of cerebellar involvement of PML as well as the need to consider a differential diagnosis of PML even in individuals with no obvious immunocompromised state.

Acute-onset chronic inflammatory demyelinating polyneuropathy after COVID-19 infection and subsequent ChAdOx1 nCoV-19 vaccination.

SARS-COV-2 predominantly results in a respiratory illness. However, it has also been associated with a wide range of neurological disorders including a broad range of immune neuropathies. These immune neuropathies associated with SARS-COV2 infection include Guillain-Barré syndrome (GBS), recurrent GBS and exacerbation of pre-existing chronic inflammatory demyelinating polyneuropathy (CIDP). We describe a case with acute-onset CIDP presenting with three relapses of demyelinating polyradiculoneuropathy, the third relapse occurring in the 8 week of illness following a previous COVID-19 infection and a recent COVID-19 vaccination with ChAdOx1 nCoV-19 and high COVID-19 antibody level. In our knowledge, this is the ever reported case of acute-onset CIDP associated with COVID-19 vaccine and high COVID-19 antibody level.

Cladophialophora bantiana brain abscess with lymphadenitis.

Cerebral phaeohyphomycosis refers to central nervous system infection by dematiaceous mould or by dark walled fungi which contain the dark pigment melanin in their cell wall which adds to the virulence of fungus. These dematiaceous fungi can cause a variety of central nervous infections including invasive sinusitis, brain abscess, meningitis, myelitis and arachnoiditis. Cladophialophora bantiana among these dematiaceous fungi is the most common cause of brain abscess in immunocompetent and immunocompromised individuals and is known to occur worldwide though is predominantly reported from subtropical regions especially the Asian subcontinent. It is difficult to differentiate these abscesses radiologically from high-grade gliomas, primary central nervous system lymphoma or other infections including toxoplasmosis, nocardiosis, tuberculosis and listeriosis. We describe a 19-year-old male patient with a cerebral abscess caused by C. bantiana where the diagnosis could be suspected by typical MR spectroscopic findings and by identifying the fungus from a lymph node biopsy.

Consensus Statement - Suggested Recommendations for Acute Stroke Management during the COVID-19 Pandemic: Expert Group on Behalf of the Indian Stroke Association.

The ongoing pandemic of COVID-19 is a global public health emergency. This has led to challenges for healthcare facilities to optimally manage other important medical emergencies. Stroke is an important public health emergency with significant mortality and morbidity. Timely treatment of acute stroke is critical to prevent disability. The current expert consensus statement on behalf of the Indian Stroke Association outlines the issues and suggestions related to the management of stroke during this ongoing COVID-19 pandemic.

Simultaneous 18F- FDG PET/MRI in Autoimmune Limbic Encephalitis.

Limbic encephalitis is an autoimmune disorder characterized by inflammation of the brain with rapidly progressing dementia which requires definitive neurological evaluation. We describe both clinical as well as imaging findings in a case of limbic encephalitis using positron emission tomography/magnetic resonance imaging.

A call for neurologists to take up stroke intervention.

Recent data have provided overwhelming evidence in favor of benefits of emergent endovascular intervention in large vessel acute ischemic stroke (AIS). India with its large population has a huge burden of AIS. Hence, neurologists need to gear up to the new challenge of providing interventional care to huge populations of AIS in the country. The best way to cover this unprecedented unmet need is to encourage neurologists to take up interventional subspecialty interests through new but sound training pathways.

Primary intraventricular central nervous system lymphoma in an immunocompetent patient.

We report a young 15-year-old boy with 6 months history of headache, vomiting, and seizure. He underwent septostomy followed by right ventriculoperitoneal shunt for obstructive hydrocephalus and was managed with empirical antituberculosis treatment. Magnetic resonance imaging (MRI) revealed solid, nodular, enhancing masses in bilateral lateral ventricles and 4(th) ventricle. Surgical biopsy from 4(th) ventricular lesion confirmed a B-cell lymphoma. Staging evaluation with MRI positron emission tomography and bone marrow biopsy were normal suggesting an intraventricular primary central nervous system lymphoma.

An unusual cause of ischemic stroke - Cerebral air embolism.

Air embolism is a preventable, often undiagnosed but potentially treatable cause of ischemic stroke with a high morbidity and mortality. It is usually iatrogenic ocurring especially in patients in ICU setting. We describe the case and neuroimaging of a patient with ischaemic stroke due to air embolism during manipulation of central venous line. We also review the literature with respect to aetiology, incidence pathophysiology, diagnosis, and treatment options for venous and air embolism. Cerebral air embolism should be considered in patients with sudden neurological deterioration after central venous or arterial manipulations or certain neurological procedures. Prevention, as well as early diagnosis and management, may reduce morbidity and mortality.

Pediatric anti-N methyl D aspartate receptor encephalitis.

Anti-N Methyl D Aspartate Receptor encephalitis (anti-NMDARE) is a recently defined disease, which is probably more under-recognized than rare. We report a case of anti-NMDARE in a 13-years-old girl, who presented with intractable seizures. To the best of our knowledge, this is the second case of pediatric anti-NMDARE being reported from India. The need for a greater awareness of this disease and the subtle differences in clinical presentation between pediatric and adult patients are highlighted.

Young girl with abnormal behavior: Anti-N-Methyl-D-Aspartate receptor immune encephalitis.

Anti N Methyl D Aspartate receptor immune encephalitis (Anti NMDARE) is a recently defined, under-recognized and often misdiagnosed disease, which typically occurs in young females and may be associated with an underlying tumor, usually ovarian teratoma. If diagnosed early, initiation of immunotherapy and tumor removal (if present) may result in recovery. We report a case of a 17 years old girl with Anti NMDARE who was initially misdiagnosed as Functional psychosis, Neuroleptic Malignant Syndrome and Sepsis syndrome. To the best of our knowledge, this is only the second case of anti NMDARE being reported from India. This case report underscores the need for a greater awareness of this entity across multiple specialties, e.g., general medicine, psychiatry and neurology, to ensure a heightened diagnostic suspicion, which can lead to timely diagnosis and adequate therapy of this treatable disease.

Paraneoplastic cerebellar degeneration in Hodgkin's lymphoma.

Paraneoplastic cerebellar degeneration (PCD) is a rare disorder presenting typically with acute or subacute severe cerebellar ataxia. PCD is most commonly associated with small cell lung cancer followed by adenocarcinoma of breast and ovary, and Hogdkin's lymphoma. We report a case of a 54-year-old male with acute-onset pancerebellar syndrome with underlying Hodgkin's lymphoma. A high index of suspicion of PCD resulted in arriving at an early diagnosis of underlying Hodgkin's disease. The patient was managed with six cycles of chemotherapy, which resulted in clinical stabilization and reversal of magnetic resonance imaging abnormalities. Antitumor therapy appears to have a significant impact on reversing PCD and hence early diagnosis and intervention for the primary remains the corner stone in stabilizing the neurological condition.

Cortical blindness after contrast-enhanced CT scan in a patient of sarcoidosis - Is it related to posterior reversible encephalopathy syndrome?

Transient cortical blindness (TCB) is a well known but rare complication of administration of contrast agent. In this case report, we present a 53-year-old woman who is a follow-up case of sarcoidosis and developed TCB with focal neurological symptoms following contrast-enhanced computed tomography scan. Magnetic resonance imaging revealed bilateral T2/Flair hyperintensities in parieto-occipital, high frontal, and cerebellar hemispheres with involvement of corpus callosum. Clinically and radiologically patient improved significantly in 4 days. The exact mechanism is still speculative and its possible relationship with posterior reversible encephalopathy syndrome is briefly discussed. The patient's symptoms were presumed to be exacerbated by presence of hypertension, underlying autoimmune disorder, sepsis, and high osmolality of contrast agent. Though there is no definite evidence to suggest that a certain treatment regimen improves the natural history of this disease but control of risk factors can possibly prevent this rare but devastating complication.