Autoimmune Encephalitis in Children: A Short Review Volume 1 - Issue 2

Shubhankar Mishra*

• Senior resident, Department of Neurology, SCB Medical College, India

Received: February 15, 2018;   Published: February 22, 2018

*Corresponding author: Shubhankar Mishra, Senior resident, Department of Neurology, SCB Medical College, Cuttack, Odisha, India

DOI: 10.32474/PAPN.2018.01.000109

Abstract PDF

Autoimmune encephalitis (AE) comprises an expanding group of clinical syndromes that can occur at all ages, but preferentially affect younger adults and children. These disorders associate with antibodies against neuronal cell surface proteins and synaptic receptors involved in synaptic transmission, plasticity, or neuronal excitability. The spectrums of symptoms include psychosis, catatonia, alterations of behaviour and memory, seizures, abnormal movements, and autonomic dysregulations. Inflammatory findings in the cerebrospinal fluid may be present. Magnetic resonance imaging (MRI) may also demonstrate abnormalities for better diagnosis, particularly on fluid- attenuated inversion recovery or T2-weighted images. Patients may initially be diagnosed with idiopathic encephalitis, likely viral but with negative viral studies. Autoimmune encephalitis should be included in the differential diagnosis of any patient, especially if young, with a rapidly progressive encephalopathy of unclear origin. AE is well responsive to immune therapy, with prompt diagnosis and treatment strongly beneficial.

Keywords: Autoimmune encephalitis; NMDA; Steroids

Abbreviations: AE: Autoimmune encephalitis; MRI: Magnetic Resonance Imaging

Encephalitis refers to an inflammatory disorder of the brain causing disastrous symptomatologies. The causes of encephalitis are numerous but finding a causative agent is always a difficult task. A study by the California Encephalitis Project, a centre focused in the epidemiology and aetiology of encephalitis, found that 63% of the patients remained without an aetiology after a battery of tests for 16 potential infectious agents [1]. Recently many auto antibodies are discovered who target specific antigens in the CNS and cause features of clinical encephalitis [2]. The immunological trigger of autoimmune encephalitis is varied and in many cases yet to be established. In some patients the presence of a systemic tumour that expresses the target neuronal/synaptic proteins appears to be important, but it's more common in adult age groups. Any immunological type of autoimmune encephalitis can have a relapsing course and therefore the diagnosis of these disorders should be considered in patients with a past history of encephalitis or relapsing encephalopathy [3-8] (Table 1).

Table 1: classification, mechanism and salient features of autoimmune encephalopathy.

Despite the severity of many patients' symptoms, the majority of patients respond to treatment. Recovery can be slow and some disorders have a tendency to relapse. Corticosteroids and/ or intravenous immunoglobulins (IVIg) or plasma exchange are considered first-line therapies and should be considered in all patients. If the AE is associated with paraneoplastic picture then the primary tumor should be treated first. Patients who do not respond to the first-line therapies second-line immunotherapy with rituximab and/or cyclophosphamide should be started very soon [9-15].

AE is not so uncommon in children. They mostly mimic different psychiatric diseases. Most of the diseases are treatable. Steroid and other immunotherapy form primary treatment modality. Any child with features of unexplained psychosis, dementia, seizure, autonomic dysfunctions etc should be suspected for possibility of AE after ruling out other common causes. All neurophysicians as well as pediatricians must possess adequate knowledge about AE for early diagnosis and better management

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