Encephalitis: diagnosis, management and recent advances in the field of encephalitides

Abstract

Encephalitis describes inflammation of the brain parenchyma, typically caused by either an infectious agent or through an autoimmune process which may be postinfectious, paraneoplastic or idiopathic. Patients can present with a combination of fever, alterations in behaviour, personality, cognition and consciousness. They may also exhibit focal neurological deficits, seizures, movement disorders and/or autonomic instability. However, it can sometimes present non-specifically, and this combined with its many causes make it a difficult to manage neurological syndrome. Despite improved treatments in some forms of encephalitides, encephalitis remains a global concern due to its high mortality and morbidity. Prompt diagnosis and administration of specific and supportive management options can lead to better outcomes. Over the last decade, research in encephalitis has led to marked developments in the understanding, diagnosis and management of encephalitis. In parallel, the number of autoimmune encephalitis syndromes has rapidly expanded and clinically characteristic syndromes in association with pathogenic autoantibodies have been defined. By focusing on findings presented at the Encephalitis Society’s conference in December 2021, this article reviews the causes, clinical manifestations and management of encephalitis and integrate recent advances and challenges of research into encephalitis.

Increased volume of cerebral oedema is associated with risk of acute seizure activity and adverse neurological outcomes in encephalitis – regional and volumetric analysis in a multi-centre cohort

“…Encephalitis is inflammation of the brain parenchyma, most commonly caused either by an infectious agent or an autoimmune process [1,2]. Patients present clinically with an acute encephalitis syndrome (AES) as defined by the World Health Organisation (WHO) [3,4], which is a combination of fever or coryzal illness and alterations in behaviour, personality, consciousness, or seizure activity.…”

Neurological manifestations of scrub typhus infection: A systematic review and meta-analysis of clinical features and case fatality

“…Scrub typhus is an increasingly prevalent cause of neurological infection in endemic regions [ 9 ]. In this systematic review and meta-analyses of 20 studies representing 1,221 patients, we investigated the clinical features and CFR in patients with CNS scrub typhus.…”

“…The mean (SD) age was 29.1 (19.0) and 573 (46.9%) were female. Patients presented to hospital after a median (IQR) duration of symptoms of 7.9 (7.0-9.2) days and had a median (IQR) Glasgow coma scale (GCS) score of 11/15 (9)(10)(11)(12)(13)(14)(15). Complete treatment data were available for 859 cases of whom 389 (45.3%) were treated with doxycycline monotherapy and 379 (44.1%) with azithromycin only.…”

“…As a result, recent epidemiological studies have suggested that scrub typhus is now a leading cause of CNS infections in endemic regions [6][7][8]. As changing ecology may increase the prevalence of arthropod-borne CNS infections populations globally [9], neurological manifestations of scrub typhus may become an emerging public health beyond current endemic regions.…”

Sequelae of neurological infection: management in primary care

“…Neurological follow‐up is also important in managing seizure disorders, which are common following neurological infection 24–26 . Seizures often occur in the first days to a week after brain injury, but could present to primary care many months or even years later.…”