Human T-cell lymphotropic virus (HTLV)-associated encephalopathy: an under-recognised cause of acute encephalitis? Case series and literature review

Human T-cell lymphotropic virus (HTLV)-1-associated myelopathy (HAM) is well described. Clinical features are predominantly consistent with cord pathology, though imaging and autopsy studies also demonstrate brain inflammation. In general, this is subclinical; however, six cases have previously been reported of encephalopathy in HTLV-1-infected patients, without alternative identified aetiology. We describe three further cases of encephalitis in the UK HAM cohort (n = 142), whereas the annual incidence of acute encephalitis in the general population is 0.07-12.6 per 100,000. Clinical features included reduced consciousness, fever/hypothermia, headaches, seizures, and focal neurology. Investigation showed: raised CSF protein; pleocytosis; raised CSF:peripheral blood mononuclear cell HTLV-1 proviral load ratio; and MRI either normal or showing white matter changes in brain and cord. Four of the six previous case reports of encephalopathy in HTLV-infected patients also had HAM. Histopathology, reported in three, showed perivascular predominantly CD8+ lymphocytic infiltrates in the brain. One had cerebral demyelination, and all had cord demyelination. We have reviewed the existing six cases in the literature, together with our three new cases. In all seven with HAM, the spastic paraparesis deteriorated sub-acutely preceding encephalitis. Eight of the nine were female, and four of the seven treated with steroids improved. We propose that HTLV-associated encephalopathy may be part of the spectrum of HTLV-1-induced central nervous system disease

UK-Wide Surveillance of Neurological and Neuropsychiatric Complications of COVID-19: The First 153 Patients

Background: Increasingly neurological complications of COVID-19 are identified, mostly in small series. Larger studies have been limited by both geography and specialty. Consequently, the breadth of complications is not represented. Comprehensive characterization of clinical syndromes is critical to rationally select and evaluate potential therapies. / Methods: During the exponential pandemic phase, we developed coordinated online portals for rapid notification across the spectrum of major UK neuroscience bodies, representing neurology, stroke, psychiatry, and intensive care. Evidence of infection and clinical case definitions were applied prospectively. Cases were compared to overall Government Public Health COVID-19 reporting. / Findings: Within three weeks, 153 cases were notified, both geographically and temporally representative of overall COVID-19 Public Health reports. Median (range) age was 71 (23-94) years. 77 (62%) had a cerebrovascular event: 57 (74%) ischemic strokes, nine (12%) intracerebral hemorrhages, and one CNS vasculitis. The second most common group were 39 (31%) who had altered mental status, including 16 (41%) with encephalopathy of whom seven (44%) had encephalitis. The remaining 23 (59%) had a psychiatric diagnosis of whom 21 (92%) were new diagnoses; including ten (43%) with psychosis, six (26%) neurocognitive (dementia-like) syndrome, and 4 (17%) an affective disorder. Cerebrovascular events predominated in older patients. Conversely, altered mental status, whilst present in all ages, had disproportionate representation in the young. / Interpretation: This is the first nationwide, cross-specialty surveillance study of acute complications of COVID-19 in the nervous system. Alteration in mental status was common, reflecting encephalopathy/encephalitis and primary psychiatric diagnoses, often in young patients. These data provide valuable and timely information urgently needed by clinicians, researchers, and funders to inform immediate steps in COVID-19 neuroscience research and health policy throughout the areas of neurology and neuropsychiatry

UK-Wide Surveillance of Neurological and Neuropsychiatric Complications of COVID-19: The First 153 Patients

Background: Increasingly neurological complications of COVID-19 are identified, mostly in small series. Larger studies have been limited by both geography and specialty.Consequently, the breadth of complications is not represented. Comprehensive characterization of clinical syndromes is critical to rationally select and evaluate potential therapies.Methods: During the exponential pandemic phase, we developed coordinated online portals for rapid notification across the spectrum of major UK neuroscience bodies, representing neurology, stroke, psychiatry, and intensive care. Evidence of infection and clinical case definitions were applied prospectively. Cases were compared to overall Government Public Health COVID-19 reporting.Findings: Within three weeks, 153 cases were notified, both geographically and temporally representative of overall COVID-19 Public Health reports. Median (range) age was 71 (23-94) years. 77 (62%) had a cerebrovascular event: 57 (74%) ischemic strokes, nine (12%) intracerebral hemorrhages, and one CNS vasculitis.The second most common group were 39 (31%) who had altered mental status, including 16 (41%) with encephalopathy of whom seven (44%) had encephalitis. The remaining 23 (59%) had a psychiatric diagnosis of whom 21 (92%) were new diagnoses; including ten (43%) with psychosis, six (26%) neurocognitive (dementia-like) syndrome, and 4 (17%) an affective disorder. Cerebrovascular events predominated in older patients. Conversely, altered mental status, whilst present in all ages, had disproportionate representation in the young.Interpretation: This is the first nationwide, cross-specialty surveillance study of acute complications of COVID-19 in the nervous system. Alteration in mental status was common, reflecting encephalopathy/encephalitis and primary psychiatric diagnoses, often in young patients.These data provide valuable and timely information urgently needed by clinicians, researchers, and funders to inform immediate steps in COVID-19 neuroscience research and health policy throughout the areas of neurology and neuropsychiatry

Spectrum, risk factors and outcomes of neurological and psychiatric complications of COVID-19: a UK-wide cross-sectional surveillance study

SARS-CoV-2 is associated with new-onset neurological and psychiatric conditions. Detailed clinical data, including factors associated with recovery, are lacking, hampering prediction modelling and targeted therapeutic interventions. In a UK-wide cross-sectional surveillance study of adult hospitalized patients during the first COVID-19 wave, with multi-professional input from general and sub-specialty neurologists, psychiatrists, stroke physicians, and intensivists, we captured detailed data on demographics, risk factors, pre-COVID-19 Rockwood frailty score, comorbidities, neurological presentation and outcome. A priori clinical case definitions were used, with cross-specialty independent adjudication for discrepant cases. Multivariable logistic regression was performed using demographic and clinical variables, to determine the factors associated with outcome. A total of 267 cases were included. Cerebrovascular events were most frequently reported (131, 49%), followed by other central disorders (95, 36%) including delirium (28, 11%), central inflammatory (25, 9%), psychiatric (25, 9%), and other encephalopathies (17, 7%), including a severe encephalopathy (n = 13) not meeting delirium criteria; and peripheral nerve disorders (41, 15%). Those with the severe encephalopathy, in comparison to delirium, were younger, had higher rates of admission to intensive care and a longer duration of ventilation. Compared to normative data during the equivalent time period prior to the pandemic, cases of stroke in association with COVID-19 were younger and had a greater number of conventional, modifiable cerebrovascular risk factors. Twenty-seven per cent of strokes occurred in patients 60 years old, the younger stroke patients presented with delayed onset from respiratory symptoms, higher rates of multi-vessel occlusion (31%) and systemic thrombotic events. Clinical outcomes varied between disease groups, with cerebrovascular disease conferring the worst prognosis, but this effect was less marked than the pre-morbid factors of older age and a higher pre-COVID-19 frailty score, and a high admission white cell count, which were independently associated with a poor outcome. In summary, this study describes the spectrum of neurological and psychiatric conditions associated with COVID-19. In addition, we identify a severe COVID-19 encephalopathy atypical for delirium, and a phenotype of COVID-19 associated stroke in younger adults with a tendency for multiple infarcts and systemic thromboses. These clinical data will be useful to inform mechanistic studies and stratification of patients in clinical trials

Diagnostic Pathways as Social and Participatory Practices: The Case of Herpes Simplex Encephalitis

Herpes simplex virus (HSV) encephalitis is a potentially devastating disease, with significant rates of mortality and co-morbidities. Although the prognosis for people with HSV encephalitis can be improved by prompt treatment with aciclovir, there are often delays involved in the diagnosis and treatment of the disease. In response, National Clinical Guidelines have been produced for the UK which make recommendations for improving the management of suspected viral encephalitis. However, little is currently known about the everyday experiences and processes involved in the diagnosis and care of HSV encephalitis. The reported study aimed to provide an account of the diagnosis and treatment of HSV encephalitis from the perspective of people who had been affected by the condition. Thirty narrative interviews were conducted with people who had been diagnosed with HSV encephalitis and their significant others. The narrative accounts reveal problems with gaining access to a diagnosis of encephalitis and shortfalls in care for the condition once in hospital. In response, individuals and their families work hard to obtain medical recognition for the problem and shape the processes of acute care. As a consequence, we argue that the diagnosis and management of HSV encephalitis needs to be considered as a participatory process, which is co-produced by health professionals, patients, and their families. The paper concludes by making recommendations for developing the current management guidelines by formalising the critical role of patients and their significant others in the identification, and treatment of, HSV encephalitis

Challenge of the unknown. A systematic review of acute encephalitis in non-outbreak situations.

BACKGROUND: The threat of emerging infections and recognition of novel immune-mediated forms of encephalitis has raised the profile of this condition in recent years. Incidence is poorly defined and most cases have an unknown cause. There is currently much interest in identification of new microbial agents of encephalitis, but no work has investigated systematically reasons for lack of pathogen identification in studies. METHODS: We systematically reviewed published literature on incidence and etiology of encephalitis in non-outbreak settings and explored possible explanations for the large number of cases of unknown etiology. RESULTS: Annual incidence ranged from 0.07 to 12.6 cases per 100,000 population with an evident decrease over time (p = 0.01). The proportion of cases with unknown etiology was high across studies (>50% in 26 of 41 studies), with strong evidence of heterogeneity in study findings (p < 0.001). Our meta-regression identified study period, setting, and subsyndrome to be the main contributors to between-study variation, rather than methodologic factors such as study design, case definitions, sample types, and testing strategies. CONCLUSIONS: Our findings support the hypothesis that new and emerging infectious agents, or new forms of immune-mediated encephalitis, may be responsible for cases currently of unknown cause and encourage the ongoing global effort to identify these. Our review highlights research areas that might lead to a better understanding of the causes of encephalitis and ultimately reduce the morbidity and mortality associated with this devastating condition

Chronic pain and cognitive impairment: a cross-sectional study in people living with HIV

Cognitive impairment and chronic pain are amongst the most prevalent neurological sequelae of HIV infection, yet little is understood about the potential bidirectional relationship between the two conditions. Cognitive dysfunction can occur in chronic pain populations whilst those with cognitive impairment can display modified responses to experimentally induced painful stimuli. To date, this has not been explored in HIV cohorts. This study aimed to identify any contribution of chronic pain to cognitive impairment in HIV and to determine differences in pain characteristics between those with and without cognitive dysfunction. This was an observational cohort study involving people living with HIV (n = 148) in the United Kingdom. Participants underwent validated questionnaire-based measurement of pain severity, interference and symptom quality as well as conditioned pain modulation and quantitative sensory testing. All participants completed a computer-based cognitive function assessment. Fifty-seven participants met the criteria for cognitive impairment and 73 for chronic pain. The cognitive impairment group had a higher prevalence of chronic pain (p = 0.004) and reported more neuropathic symptoms (p = 0.001). Those with chronic pain performed less well in emotional recognition and verbal learning domains. The interaction identified between chronic pain and cognitive dysfunction warrants further exploration to identify causal links or shared pathology