Limbic encephalitis and psychosis

Anti-Leucine-Rich Glioma-Inactivated 1 (Anti-LGI 1) Limbic Encephalitis and New-Onset Psychosis: A Case Report

Anti-leucine-rich glioma-inactivated 1 limbic encephalitis (Anti-LGI 1 LE) is a subtype of autoimmune encephalitis (AE) and the most common cause of limbic encephalitis (LE). Clinically, it can have an acute to sub-acute onset of confusion and cognitive impairment, facial-brachial dystonic seizures (FDBS), and psychiatric disturbances. The clinical manifestations are varied, and its diagnosis requires high clinical suspicion to avoid delay in the treatment. When patients manifest mostly psychiatric symptoms, the disease may not be immediately recognized. We aim to report a case of Anti-LGI 1 LE in which the patient presented acute psychotic symptoms and was initially diagnosed with unspecified psychosis. We present a case of a patient with sub-acute behavioral changes, short-term memory loss, and insomnia who was brought to the emergency department after a sudden episode of disorganized behavior and speech. On medical examination, the patient presented persecutory delusions and indirect signs of auditory hallucinations. An initial diagnosis of unspecified psychosis was performed. Investigations revealed right temporal epileptiform activity in the electroencephalogram (EEG), abnormal bilateral hyperintensities in the temporal lobes in the brain magnetic resonance imaging (MRI), and a positive titer of anti-LGI 1 antibodies (Abs) in serum and cerebrospinal fluid (CSF), leading to a diagnosis of anti-LGI 1 LE. The patient was treated with intravenous (IV) steroids and immunoglobulin and later with IV rituximab. In patients that predominantly present with psychotic and cognitive disorders the diagnosis of anti-LGI 1 LE can be delayed predisposing them to a poorer prognosis (permanent cognitive impairment - especially short-term memory loss - and persistent seizures). It is necessary to be aware of this diagnosis when evaluating acute to sub-acute psychiatric illness developing with cognitive impairment (specially with memory loss) to avoid diagnosis delays and long-term sequelae.

Epilepsy, Immunity and Neuropsychiatric Disorders

Several studies have focused on the emerging role of immunity and inflammation in a wide range of neurological disorders. Autoimmune diseases involving central nervous system share well defined clinical features including epileptic seizures and additional neuropsychiatric symptoms, like cognitive and psychiatric disturbances. The growing evidence about the role of immunity in the pathophysiologic mechanisms underlying these conditions lead to the concept of autoimmune epilepsy. This relatively-new term has been introduced to highlight the etiological and prognostic implications of immunity in epileptogenesis. In this review, we aim to discuss the role of autoimmunity in epileptogenesis and its clinical, neurophysiological, neuroimaging and therapeutic implications. Moreover, we wish to address the close relationship between immunity and additional symptoms, particularly cognitive and psychiatric features, which deeply impact clinical outcomes in these patients. To assess these aspects, we first analyzed Rasmussen's encephalitis. Subsequently, we have covered autoimmune encephalitis, particularly those associated with autoantibodies against surface neuronal antigens, as these autoantibodies express a direct immune-mediated mechanism, different from those against intracellular antigens. Then, we discussed the connection between systemic immune disorders and neurological manifestations. This review aims to highlight the need to expand knowledge about the role of inflammation and autoimmunity in the pathophysiology of neurological disorders and the importance to early recognize these clinical entities. Indeed, early identification may result in faster recovery and a better prognosis.

Brain anomalies in early psychosis: From secondary to primary psychosis

Brain anomalies are frequently found in early psychoses. Although they may remain undetected for many years, their interpretation is critical for differential diagnosis. In secondary psychoses, their identification may allow specific management. They may also shed light on various pathophysiological aspects of primary psychoses. Here we reviewed cases of secondary psychoses associated with brain anomalies, reported over a 20-year period in adolescents and young adults aged 13-30 years old. We considered age at first psychotic symptoms, relevant medical history, the nature of psychiatric symptoms, clinical red flags, the nature of the brain anomaly reported, and the underlying disease. We discuss the relevance of each brain area in light of normal brain function, recent case-control studies, and postulated pathophysiology. We show that anomalies in all regions, whether diffuse, multifocal, or highly localized, may lead to psychosis, without necessarily being associated with non-psychiatric symptoms. This underlines the interest of neuroimaging in the initial workup, and supports the hypothesis of psychosis as a global network dysfunction that involves many different regions.

Do patterns of synaptic pruning underlie psychoses, autism and ADHD?

This review of available longitudinal structural imaging and immunological findings in first-onset schizophrenia, bipolar disorder, attention-deficit hyperactivity disorder (ADHD) and autism suggests that different patterns of synaptic pruning lead to various phenotypes. Proposals for future research strategies to try to replicate these findings are suggested, potential biomarkers to assist in diagnosis and determining the optimum duration of maintenance treatment are considered and ideas of potential immunotherapy augmentation are outlined.

LEARNING OBJECTIVES

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DECLARATION OF INTEREST

None.

A clinical approach to new-onset psychosis associated with immune dysregulation: the concept of autoimmune psychosis

Growing data point to the overlap between psychosis and pathological processes associated with immunological dysregulation as well as inflammation. Notably, the recent discovery of antibodies against synaptic and neuronal cell membrane proteins such as anti-N-methyl-d-aspartate receptor provides more direct evidence of the etiological connection between autoimmunity and subsequent hazard of psychosis. Here, we advocate the use of term “autoimmune psychosis,” as this term suggests that autoimmune disorders can masquerade as drug-resistant primary psychosis, and this subtype of psychosis has anatomical and immunological footprints in the brain, despite the frequent absence of structural abnormalities on conventional brain MRI. Furthermore, this term might serve as a reminder not to overlook appropriate neurological workup such as neuroimaging and EEG testing, as well as CSF analysis, for cases with acute or subacute atypical onset of neuropsychiatric presentations including those dominated by acute psychotic symptoms. We propose etiologically and serologically oriented subclassification as well as multi-modal diagnostic approach to address some of the challenges inherent to early diagnosis of patients presenting with atypical and refractory new-onset psychotic symptoms of autoimmune origin. This is particularly relevant to the diagnosis of seronegative but probable autoimmune psychosis (SPAP) that might masquerade as antipsychotic drug-resistant primary psychotic disorder. This distinction is therapeutically important as autoimmune-related psychotic symptomatology can frequently respond well to timely treatment with proper immune modulatory therapies.

Clinical characterization of autoimmune encephalitis and psychosis

BACKGROUND AND PURPOSE

Autoimmune disorders are growing alarmingly high in prevalence across the globe. Autoimmune encephalitis has had a dramatic impact on the medical field, effectually altering diagnostic and treatment paradigms in regard to neuropsychiatric disorders. Our primary goal in conducting this study was to analyze the clinical characteristics of autoimmune encephalitis patients, with special focus on psychiatric presentations, in the West China Hospital and report patient prognoses after immunotherapy.

METHODS

Data for patients admitted to the West China Hospital with autoimmune encephalitis diagnoses from 2015 to 2016 were collected and the corresponding clinical features were analyzed.

RESULTS

We ultimately included 70 patients with autoimmune encephalitis: 56 (80%) anti-NMDAR encephalitis patients, 8 (11%) LGI1 antibody encephalitis patients, and 6 (9%) GABAbR antibody encephalitis patients. The median age of the 70 patients was 33years, 40% were female, and the initial symptoms in 31 patients (44%) were psychiatric in nature. Psychiatric disturbance appeared in 58 patients (83%) during inpatient treatment, after which 57 patients (81%) recovered.

CONCLUSIONS

Many patients with autoimmune encephalitis present psychotic symptoms; psychiatric symptoms typically appear before neurological features emerge. Timely diagnosis and treatment may yield favorable prognosis.

[Reconciliating neurology and psychiatry: The prototypical case of frontotemporal dementia]

Frontotemporal degeneration (FTD) in its behavioral variant (bvFTD) is probably one of the conditions that best illustrates the links between psychiatry and neurology. It is indeed admitted that between a third and half of patients with this condition, especially in early-onset forms, receive an initial diagnosis of psychiatric disorder (depression, schizophrenia, bipolar disorder) and are then referred to a psychiatric ward. BvFTD can thus be considered a neurological disorder with a psychiatric presentation. Among psychiatric symptoms reported in this disease, psychotic symptoms (hallucinations, delusions, especially of persecution), which have long been underestimated in bvFTD and are not part of the current diagnostic criteria, are present in about 20% of cases and may be inaugural. They are particularly common in the genetic forms related to a mutation in the C9orf72 gene (up to 50%), and to a lesser extent in the GRN gene (up to 25%). C9orf72 gene mutation is often associated with a family history of dementia or motor neuron disease but also of psychiatric disorders. It has also been described in sporadic presentation forms. Sometimes, the moderate degree of brain atrophy on MRI described in patients carrying this mutation may complicate the differential diagnosis with late-onset psychiatric diseases. In the present article, we underline the importance of considering that psychiatric - especially psychotic - symptoms are not rare in bvFTD, which should lead to a revision of the diagnostic criteria of this disease by taking greater account of this fact. We also propose a diagnostic chart, based on concerted evaluation by neurologists and psychiatrists for cases of atypical psychiatric symptoms (late-onset or pharmacoresistant troubles) leading to consider the possibility of a neurological disorder, in order to shed a new light on these difficult clinical situations. In the field of research, bvFTD may constitute a model to explore the neural basis of certain psychiatric disorders, and a possible molecular link between bvFTD and psychoses, which could eventually lead to new therapeutic approaches, has been recently suggested. Thus, bvFTD illustrates how the links between neurology and psychiatry are close and tend to evolve with the progress of scientific knowledge. It is necessary to strengthen collaboration between the two disciplines both to improve the care - diagnosis and management of these patients - and to promote the emergence of innovative clinical research.

Autoimmune neurological syndromes associated limbic encephalitis and paraneoplastic cerebellar degeneration

INTRODUCTION

Autoimmune neurological syndrome is a group of disorders caused by cancer affecting nervous system by different immunological mechanisms. In this study, we aim to study the clinical symptoms, cerebrospinal fluid (CSF) findings, autoantibody tests, computed tomography (CT), magnetic resonance imaging (MRI) signs and treatment outcome of patients with autoimmune syndromes.

METHODS

In this study, 7 patients (4 male, 3 female) diagnosed with autoimmune neurological syndrome were retrospectively examined.

RESULTS

Five of patients were diagnosed with limbic encephalitis, two of them were paraneoplastic cerebellar degeneration. Confusion and seizure were the most seen symptoms. Two patients had psychiatric disturbances (28,5%) followed by seizure. Headache was seen in 2 patients (% 28,5), disartria in 1 patient (% 14,2), and gait disorder in 2 patients (28,5%). The duration of symptoms was 46 (3-150) days on average. CSF abnormalities were detected in 2 patients. CT and MRI of the brain was available in all patients. Five patients had involvement of mesiotemporal region, two patients had diffuse cerebellar atrophy. One of patients had anti-GABAR B1 positivity. Tumors were detected in 2 patients while investigation for paraneoplasia screening.

CONCLUSION

Remission is only possible with the detection and treatment of the malignancy. Early diagnosis and treatment are of paramount importance.

Paraneoplastic limbic encephalitis with prominent neuropsychiatric apathy

The spectrum of paraneoplastic neurologic syndromes has increased with the description of encephalitis associated with antibodies against cell surface and synaptic proteins. Subacute cognitive impairment, movement disorders, late onset epilepsy and neuropsychiatric syndromes were recently linked to paraneoplastic encephalitis. Despite that, probably some syndromes and antibodies are yet to be reported. Herein we reported the clinical and neuroimaging pictures of a patient with late onset medial temporal lobe epilepsy, subtle cognitive impairment, psychosis and severe apathy diagnosed with antibody-negative paraneoplastic encephalitis due to colonic adenocarcinoma. The apathy markedly improved after removal of the tumor, without concomitant immunotherapy (steroids, intravenous immunoglobulins, immunosuppressants, plasmapheresis, etc.). Our report highlights the importance of a full clinical and neurologic investigation in cases of atypical neuropsychiatric presentations, particularly in the elderly and with the concomitance of epilepsy and cognitive decline. Even chronic presentations must be considered. Neuroimaging is an important tool to demonstrate structural and functional brain dysfunction in these cases. Colonic adenocarcinoma should be searched for in cases in which a typical tumor related to paraneoplastic neurologic syndromes is not found.