Consensus guidelines for the investigation and management of encephalitis in adults and children in Australia and New Zealand

Abstract

Encephalitis is a complex neurological syndrome caused by inflammation of the brain parenchyma. The management of encephalitis is challenging because: the differential diagnosis of encephalopathy is broad; there is often rapid disease progression; it often requires intensive supportive management; and there are many aetiologic agents for which there is no definitive treatment. Patients with possible meningoencephalitis are often encountered in the emergency care environment where clinicians must consider differential diagnoses, perform appropriate investigations and initiate empiric antimicrobials. For patients who require admission to hospital and in whom encephalitis is likely, a staged approach to investigation and management is preferred with the potential involvement of multiple medical specialties. Key considerations in the investigation and management of patients with encephalitis addressed in this guideline include: Which first-line investigations should be performed?; Which aetiologies should be considered possible based on clinical features, risk factors and radiological features?; What tests should be arranged in order to diagnose the common causes of encephalitis?; When to consider empiric antimicrobials and immune modulatory therapies?; and What is the role of brain biopsy?

A clinical approach to diagnosis of autoimmune encephalitis

“…These criteria differ from those previously proposed for encephalitis (any cause or idiopathic) in which changes in the level of consciousness, fever, CSF pleocytosis, and EEG alterations are more often needed. 1,4–6 These criteria needed to be adapted for autoimmune encephalitis because patients with autoimmune encephalitis could present with memory or behavioural deficits without fever or alteration in the level of consciousness, or with normal brain MRI or CSF results. 7 In this context, memory deficits refer to the inability to form new, long-term memories owing to hippocampal dysfunction, or problems with working memory, which refers to structures and processes used for temporary storage and manipulation of information.…”

“…1,4–6 However, in the past 10 years an increasing number of non-infectious, mostly autoimmune, encephalitis cases have been identified and some of them do not meet existing criteria. 7 These newly identified forms of autoimmune encephalitis might be associated with antibodies against neuronal cell-surface or synaptic proteins (table) 8–23 and can develop with core symptoms resembling infectious encephalitis, and also with neurological and psychiatric manifestations without fever or CSF pleocytosis.…”

Identifikasi virus herpes simpleks pada anak dengan ensefalitis: sebuah studi pendahuluan

“…Dokter yang menangani anak yang sakit akut mesti paham bagaimana menangani seorang anak yang dicurigai menderita ensefalitis mengingat beberapa agen penyebab akan berespons terhadap pengobatan spesifik dan keterlambatan diagnosis dapat berakibat fatal. 1,2 Infeksi Herpes simpleks pada susunan syaraf pusat merupakan salah satu dari infeksi virus paling berat pada otak manusia. Insidennya berkisar antara 1 dalam 250.000 hingga 500.000 penduduk per tahun.…”

“…Bahkan meskipun hasil pemeriksaan mikroskopi awal CSS maupun pencitraan normal, acyclovir tetap mesti diberikan dalam 6 jam pertama rawatan bila terdapat kecurigaan klinis ke arah ensefalitis Herpes simpleks sambil menunggu hasil konfirmasi diagnosis lebih lanjut. 1,2 Di luar negeri hal ini tidaklah terlalu menjadi masalah mengingat pemeriksaan Polimerase Chain Reaction (PCR) virus Herpes simpleks pada CSS yang merupakan baku emas untuk diagnosis tersedia luas.3-5 Sementara di Indonesia, pemeriksaan PCR Herpes simpleks pada CSS belum merupakan pemeriksaan rutin yang selalu tersedia di rumah sakit. Pemberian terapi anti virus spesifik tanpa bukti diagnosis yang kuat juga merupakan problem tersendiri mengingat obat ini sangat mahal dan juga tidak termasuk ke dalam Formularium Nasional.…”

Paediatric Acute Encephalitis: Infection and Inflammation

“…A number of clinical guidelines for the management of encephalitis in children have been recently been published [20,21]. Common features of these have been the emphasis on early lumbar puncture where not contraindicated to exclude treatable causes of encephalitis (particularly HSV), the importance of early neuroimaging (preferably MRI) to confirm the diagnosis, the need to cease acyclovir where an alternative cause of encephalitis is found or HSV PCR is negative, early consultation with specialist neurologists and infectious diseases for advice re-extended investigations and diagnosis/management of autoimmune encephalitides.…”