Neuroimaging findings are sensitive and specific in diagnosis of tuberculous meningitis

Objective: The primary objective of this study was to describe the neuroimaging changes of tuberculous meningitis (TBM), and to determine the role of neuroimaging in the diagnosis of TBM. Methods: Between January 2009 and July 2015, we prospectively recruited TBM patients in two hospitals in Malaysia. Neuroimaging was performed and findings were recorded. The control consists of other types of meningo-encephalitis seen over the same period. Results: Fifty four TBM patients were recruited. Leptomeningeal enhancement was seen in 39 (72.2%) patients, commonly at prepontine cistern and interpeduncular fossa. Hydrocephalus was observed in 38 (70.4%) patients, 25 (46.3%) patients had moderate and severe hydrocephalus. Thirty four patients (63.0%) had cerebral infarction. Tuberculoma were seen in 29 (53.7%) patients; 27 (50.0%) patients had classical tuberculoma, 2 (3.7%) patients had “other” type of tuberculoma, 18 (33.3%) patients had ≥5 tuberculoma, and 11 (20.4%) patients had < 5 tuberculoma. Fifteen (37.2%) patients had vasculitis, 6 (11.1%) patients had vasospasm. Close to nine tenth (88.9%) of the patients had ≥1 classical neuroimaging features, 77.8% had ≥ 2 classical imaging features of TBM (basal enhancement, hydrocephalus, basal ganglia / thalamic infarct, classical tuberculoma, and vasculitis/vasospasm). Only 4% with other types of meningitis/encephalitis had ≥1 feature, and 1% had two or more classical TBM neuroimaging features. The sensitivity of the imaging features of the imaging features for diagnosis of TBM was 88.9% and the specificity was 95.6%. Conclusion: The classic imaging features of basal enhancement, hydrocephalus, basal ganglia/thalamic infarct, classic tuberculoma, and vasculitis are sensitive and specific to diagnosis of TBM.

Spontaneous remission without progression to limbic encephalitis in a patient with LGi1 seropositive faciobrachial dystonic seizure

Faciobrachial dystonic seizures are pathognomonic of leucine-rich glioma inactivated-1 (LGi1) antibody, non-paraneoplastic limbic encephalitis. Faciobrachial dystonic seizures usually precede limbic encephalitis by about a month. It is unknown whether, if untreated, faciobrachial dystonic seizures inevitably progress to limbic encephalitis. We present an LGi1 seropositive patient with a year’s history of faciobrachial dystonic seizures, who achieved remission spontaneously without immunotherapy or antiepileptic drug treatment, and did not develop evidence of limbic encephalitis over a three-year follow-up.

EEG is sensitive in early diagnosis of anti NMDAR encephalitis and useful in monitoring disease progress

Background& Objective: Investigation modalities, such as MRI and CSF examination, are neither sensitive nor specific in the early phase of anti-NMDAR encephalitis. Nuclear imaging may be useful to monitor the response to treatment but limited by the availability.We aimed to determine the role of EEG as a tool for early diagnosis as well as a tool to assess disease progression and response to treatment. Methods: A total of 99 EEGsdone in 16 patients diagnosed with anti-NMDAR encephalitis throughout the course of illness, were reviewed retrospectively. The EEG changes were correlated with the clinical presentations and response to treatment. Sixteen EEGs of patients with schizophrenia and mood disorder, and 10 EEGs of patients with infective encephalitis were included as control. Results: EEGs performed during the psychiatric and cognitive dysfunctionphase in patient with anti-NMDAR encephalitis, showed diffuse background slowing in the delta-theta range in all the patients. Serial EEGs showed that the dominant background frequency improved with improvement in cognitive status. Nine patients had complete recovery with normalisation of the EEG abnormalities. Eight patients had their typical clinical seizure recorded during EEG monitoring, but only 2 (25.0%) with EEG correlation. Ten patients had status epilepticus (62.5%), 5 had EEG recorded during their status epilepticus, of which only one with EEG correlation (20.0%). Eleven patients had asymmetric background (68.8%), but only 1 has correlation with focal changes in the MRI brain (9.1%). Even though the EEGs of patients with infective encephalitis also showed background slowing, their CSF analysis was supportive of an infective cause. EEGs of patients with established psychiatric disorder were within normal limits. Conclusion: EEG abnormality has a good correlation with the degree of psychiatric and cognitive dysfunction in patient with anti-NMDAR encephalitis, and is useful in early diagnosis, monitoring the progress and the response to treatment. However, it has poor correlation with clinical seizures.

Primary angiitis of the central nervous system with myelopathy as initial clinical presentation

Primary angiitis of the central nervous system (PACNS) is a rare vasculitis restricted to the central nervous system without systemic involvement. Delay in diagnosis and treatment is common due to its non-specific symptoms and lack of non-invasive diagnostic tests. Myelopathy can occur in PACNS, during the clinical course of the illness, with or without cerebral symptoms. We describe here a 51 year-old ethnic Chinese woman who presented initially with paraparesis without cerebral symptoms. The diagnosis of PACNS was eventually made from brain biopsy when she subsequently developed cerebral involvement. Despite aggressive treatment, the patient developed progressive neurological deterioration and died. This patient demonstrates the rare occurrence of myelopathy as the sole initial presentation of PACNS.

Cold allodynia as the presenting symptom in a case of acquired neuromyotonia (Isaacs syndrome) with multiple autoantibodies

We report a patient who presented with severe cold-induced allodynia and hyperhidrosis, and found to have acquired neuromyotonia (Isaacs syndrome) with high voltage-gated potassium channel (VGKC) antibody titre,positive contactin-associated protein 2 (CASPR2) and leucine-rich glioma-inactivated 1 (LGI1) antibodies. The patient also had positive anti-dsDNA and acetylcholine receptor (AChR) antibodies without clinical features of SLE or myasthenia gravis, suggesting a strong underlying autoimmune tendency. CT thorax showed no thymoma. Her symptoms improved with intravenous immunoglobulin infusion but recurred despite maintenance oral corticosteroids and carbamazepine. She has since been on regular IVIG infusions. Cold allodynia is an unusual presentation in acquired neuromyotonia.

Late-onset Nipah virus encephalitis 11 years after the initial outbreak: A case report

Nipah virus infection is known to cause late-onset and relapsed encephalitis, in addition to an acute encephalitic illness. This is a report of a 35 years old woman, who had exposure to the Nipah virus infection during the 1999 Malaysian outbreak, was positive for Nipah IgG by immunofl uorescence, and had multiple small hyperintense lesions in brain MRI typically seen in acute Nipah encephalitis patients, indicating asymptomatic Nipah virus infection. She subsequently developed acute encephalitis after 11 years, manifesting as diplopia, internuclear opthalmoplegia and epileptic seizures with pleocytosis in cerebrospinal fl uid examination. She had another episode of relapsed encephalitis a year later, with seizures, memory impairment, chorea and new lesions in MRI brain. This patient is unusual in the long incubation of 11 years before manifesting with late-onset Nipah encephalitis.

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis: A series of ten cases from a university hospital in Malaysia

Objective: To report on the incidence, and the clinical and laboratory features of patients seen at the University of Malaya Medical Centre with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. Methods: The charts of all patients admitted to the adult neurology ward with encephalitis over an 18- month period from January 2010 to June 2011 were reviewed. Diagnosis of anti-NMDAR encephalitis was based on the presence of encephalitis plus antibody against the NMDAR. Two other paediatric patients with anti-NMDAR encephalitis seen over the same period were also included in this report. Results: There was a total of 10 patients with anti-NMDAR encephalitis seen over the study period. The mean age was 18.1 years (range 9-29 years). Eight patients were female, two male. Five were Malay and fi ve were Chinese. All patients had prominent psychiatric symptoms, followed by epileptic seizures. Nine patients had a movement disorder, orofacial dyskinesia being the commonest, and all had autonomic involvement. None had an underlying tumour. Treatments consisted of corticosteroid, plasma exchange and intravenous immunoglobulin (IVIG). The clinical outcome was variable, with full recovery (2), substantial recovery (3), partial recovery (4), and mortality (1) seen. Remarkably, the eight adult cases of anti-NMDAR encephalitis accounted for 50% of the 16 cases of encephalitis seen during the study period. Conclusion: Anti-NMDAR encephalitis may be a relatively common cause of adult encephalitis among certain Asian groups. None of our cases was paraneoplastic in origin.

Progressive multifocal leukoencephalopathy limited to the posterior fossa

Progressive multifocal leukoencephalopathy (PML) is a rapidly progressive demyelinating disease caused by the reactivation of JC papova virus usually in immunocompromised hosts.1 The disease is a chronic viral infection resulting in mortality within a year.2 The condition characterized by white matter changes in multiple locations of the brain is caused by destruction of the oligodendrogliocytes.2 We report a case of AIDS associated PML presenting with progressive cerebellar symptoms, with the unusual feature of imaging abnormalities limited to the posterior fossa.

Nipah virus and bats

Since the initial outbreak in Malaysia, small outbreaks of Nipah encephalitis have been reported almost annually in Bangladesh. Epidemiological studies have shown that the virus could be transmitted from bat to human and from human to human. Wildlife studies have also shown that the virus was widely distributed in at least 10 genera and 23 species of bats in a large part of Asia and Africa – a region that stretches from Australia and southern China, and from Indonesia to as far west as Ghana, a region with a total population of more than 1.4 billion people. As bats are long distant flying, gregarious animals living in large colonies which could exchange novel viruses from one species to another, it is not unexpected that the seroprevalence of Henipavirus among bat colonies are relatively high. The widespread distribution of both the Henipavirus and its hosts also means that the virus will remain an important cause of zoonotic disease.