Hashimoto's encephalopathy: a brief review

Clinical presentations and treatment outcomes of Hashimoto encephalopathy at Siriraj Hospital - Thailand's largest national tertiary referral center

BACKGROUND

Hashimoto encephalopathy has multiple clinical presentations, and other than the presence of thyroid antibody, laboratory and imaging investigations are all non-specific. Data specific to the clinical presentations and treatment outcomes of patients with Hashimoto encephalopathy in Thailand remain scarce.

OBJECTIVES

To retrospectively investigate the clinical presentations and treatment outcomes of patients with Hashimoto encephalopathy at Siriraj Hospital.

METHODS

Patients who presented with acute encephalopathy at our center during July 2012-March 2017 were evaluated for eligibility. The inclusion criteria were positive anti-thyroperoxidase (anti-TPO) or anti-thyroglobulin (anti-Tg) in serum with negative neuronal antibody in serum or cerebral spinal fluid (CSF). Clinical presentations, symptom duration, laboratory results of thyroid status and thyroid autoantibody, CSF study, and clinical outcomes were collected.

RESULTS

Of the 204 patients who presented with encephalopathy, 31 (15.2%) were positive for the anti-TPO or anti-Tg antibody. Of those, 13 patients met the diagnostic criteria for Hashimoto encephalopathy. Clinical presentations included cognitive impairment (76.9%), clouding of consciousness (46.2%), and behavior change (30.8%). The neuropsychiatric presentations were visual hallucination (30.8%), auditory hallucination (15.4%), delusion (7.7%), and mood disturbance (23.1%). Other clinical presentations included seizure (38.5%), abnormal movement (23.1%), sleep disturbance (38.5%), ataxia (46.2%), stroke-like episode (15.4%), and fever (15.4%). Most patients (76.9%) had onset within < 3 months. Regarding outcomes, 1 patient who did not receive corticosteroid died from status epilepticus and septic shock. Among the 12 patients who received corticosteroid, 9 (75%) had marked improvement, 1 (8.3%) had slight improvement, and 2 (16.6%) had no clinical improvement. Seven patients (53.9%) had normal thyroid function, 4 patients (30.8%) had subclinical hypothyroidism, and 2 patients (15.4%) had subclinical hyperthyroidism.

CONCLUSIONS

The results of this study revealed cognitive impairment, neuropsychiatric symptoms, seizure, ataxia, and sleep disturbance to be common manifestations of Hashimoto encephalopathy. This condition should always be considered in individuals with subacute onset of unexplained cognitive impairment or cerebellar ataxia. Laboratory and neuroimaging investigations were all found to be nonspecific in Hashimoto encephalopathy. Most patients responded well to treatment, so clinical suspicion and early diagnosis and treatment will lead to improved patient outcomes.

Autoimmune-mediated encephalitis and mimics: A neuroimaging review

Autoimmune encephalitis is a category of autoantibody-mediated neurological disorders that often presents a diagnostic challenge due to its variable clinical and imaging findings. The purpose of this image-based review is to provide an overview of the major subtypes of autoimmune encephalitis and their associated autoantibodies, discuss their characteristic clinical and imaging features, and highlight several disease processes that may mimic imaging findings of autoimmune encephalitis. A literature search on autoimmune encephalitis was performed and publications from neuroradiology, neurology, and nuclear medicine literature were included. Cases from our institutional database that best exemplify major imaging features were presented.

Hashimoto's Encephalopathy Masquerading as Rapidly Progressive Dementia and Extrapyramidal Failure

Hashimoto's encephalopathy is a rare immune-mediated disorder characterized by subacute encephalopathy with elevated thyroid antibodies. Hashimoto's encephalopathy is also known as steroid-responsive encephalopathy associated with autoimmune thyroiditis. We report a rare presentation of Hashimoto's encephalopathy presenting with acute neuropsychiatric disturbances, rapidly progressive dementia, seizures, and extrapyramidal failure. Neuroimaging revealed multifocal vasculitides of major cerebral vessels that support the autoimmune vasculitic theory as the underlying pathogenesis for Hashimoto's encephalopathy. Unfortunately, permanent irreversible cerebral damage has already ensued before her presentation to our center, which rendered steroid therapy ineffective. Serological testing for Hashimoto's thyroiditis must be in the investigation of all rapidly progressive dementias as early diagnosis and timely management of autoimmune thyroiditis may salvage sizable and eloquent cerebral tissues. The rarity of the condition should not preclude the investigation of Hashimoto's disease even in the presence of normal levels of thyroid hormones. Delayed diagnosis may result in irreversibly catastrophic encephalopathy in patients who once presented with potentially curable dementia.

The Role of Pediatric Rheumatologists in Autoimmune Brain Disease

The spectrum of autoimmune and inflammatory brain diseases continues to evolve with medical advances facilitating both the detection of inflammation of the central nervous system and the discovery of novel disease mechanisms. The clinical overlap of these disorders with primary rheumatic diseases and the efficacy of immunotherapy have led to strong partnerships between pediatric rheumatologists, neurologists, psychiatrists, and other providers in the care of children with these conditions. Early diagnosis and initiation of targeted therapy improve clinical outcomes, highlighting the importance of interdisciplinary collaborative care.

Hashimoto's Encephalopathy: A Rare Cause of Seizure-like Activity

Hashimoto’s encephalopathy is an uncommon disorder that may present with a wide variety of different neurological signs and symptoms that can include acute altered level of consciousness, psychosis, seizures, ataxia, dementia, myoclonus, and stupor. We present a case of a 60-year-old female patient who was admitted to the internal medicine floor for workup for seizures of unknown etiology. Investigations, including a complete blood count, basic metabolic panel, magnetic resonance imaging (MRI) of the brain, cerebrospinal fluid analysis, and NMDA (N-methyl-D-aspartate) receptor encephalitis screen, were all unremarkable. Thyroid-stimulating hormone levels and anti-thyroid peroxidase antibodies were found to be elevated, suggesting an underlying etiology of Hashimoto’s thyroiditis. Treatment with corticosteroids and levothyroxine can lead to resolution of symptoms. This case report is presented to suggest the importance of serological screening for anti-thyroid antibodies in the workup of all patients with unknown causes of encephalopathy along with providing a review of the literature.

Anti-Thyroid Peroxidase/Anti-Thyroglobulin Antibody-Related Neurologic Disorder Responsive to Steroids Presenting with Pure Acute Onset Chorea

Background:

Pure acute onset chorea without encephalopathy has rarely been reported in anti-thyroid peroxidase (anti-TPO)/anti-thyroglobulin (anti-TG) antibody-related neurologic disorders responsive to steroids (ATANDS).

Case report:

We report a 16-year-old female who presented with acute chorea without encephalopathy. Anti-TPO antibodies were found to be strongly positive (>1200 IU/ml) along with anti-thyroglobulin and anti-thyroid stimulating hormone receptor antibodies. After pulse intravenous methylprednisolone therapy (1 g/day for five consecutive days), all the movements seized, and she was discharged with oral prednisolone 30 mg/day with gradual tapering over next three months. After one year of follow-up, she is stable, drug-free, and never had any other problems.

Discussion:

Anti-thyroid antibodies testing should be included in routine/conventional panel that is done for elucidating causes of chorea as ATANDS can be easily missed and is treatable with widely available, relatively low-cost drugs like steroids with a promising outcome.

The S1P-S1PR Axis in Neurological Disorders-Insights into Current and Future Therapeutic Perspectives

Sphingosine 1-phosphate (S1P), derived from membrane sphingolipids, is a pleiotropic bioactive lipid mediator capable of evoking complex immune phenomena. Studies have highlighted its importance regarding intracellular signaling cascades as well as membrane-bound S1P receptor (S1PR) engagement in various clinical conditions. In neurological disorders, the S1P–S1PR axis is acknowledged in neurodegenerative, neuroinflammatory, and cerebrovascular disorders. Modulators of S1P signaling have enabled an immense insight into fundamental pathological pathways, which were pivotal in identifying and improving the treatment of human diseases. However, its intricate molecular signaling pathways initiated upon receptor ligation are still poorly elucidated. In this review, the authors highlight the current evidence for S1P signaling in neurodegenerative and neuroinflammatory disorders as well as stroke and present an array of drugs targeting the S1P signaling pathway, which are being tested in clinical trials. Further insights on how the S1P–S1PR axis orchestrates disease initiation, progression, and recovery may hold a remarkable potential regarding therapeutic options in these neurological disorders.

Hashimoto's Encephalopathy Mimicking Viral Encephalitis: A Case Report

Hashimoto's encephalopathy (HE) is a rare neuropsychiatric syndrome characterized by elevated levels of anti-thyroid antibodies. Diverse manifestations make timely diagnosis of HE difficult. Herein, we report a case of HE, in which the clinical symptoms and laboratory test results mimicked viral encephalitis. A 59-year-old male patient, who presented with a fever, headache, slow and unclear speech, sentence confusion, elevated levels of anti-thyroid antibodies in the serum, an increased white blood cell count, and positivity for anti-thyroid antibodies in the CSF, was finally diagnosed with HE and responded well to a small dose of methylprednisolone. This report helps bring the attention of clinicians to the fact that HE should be considered when cases of unexplained encephalopathy are encountered.

Hashimoto`s Encephalopathy Presenting with Progressive Cerebellar Ataxia

Hashimoto`s encephalopathy is a rare neurological syndrome occurring in patients with autoimmune thyroid disease. The diagnosis of Hashimoto`s encephalopathy is based on the clinical picture with the presence of serum anti-thyroid antibodies regardless of the thyroid disorder. Acquired cerebellar ataxia associated with Hashimoto`s disease is a rare occurrence. In this article, we present a case who had progressive non-familial autoimmune pancerebellar disease in association with an increased level of thyroid peroxidase and thyroglobulin antibodies. The patient was managed aggressively with both intravenous immunoglobulins and plasma exchange, which stopped the progression of the disease and allowed for slow improvement. Early diagnosis of Hashimoto`s encephalopathy with autoimmune cerebellar ataxia and intervention with immunomodulatory therapy are of paramount importance. Close monitoring after steroid therapy is important since some patients with this rare disease might be resistant to steroid therapy and require aggressive immunomodulatory therapy.

Immune mediated pediatric encephalitis - need for comprehensive evaluation and consensus guidelines

Background

Autoimmune encephalitis is characterized by neuropsychiatric symptoms associated with brain inflammation. The differential is usually broad and Psychiatry often collaborates with Neurology in diagnostic clarification and symptom management. At least 40% of neuroencephalitis cases are of unknown etiology which adds to difficulties in making the right diagnosis and deciding on the appropriate treatment (Granerod et al., Lancet Infect Dis 10:835-44, 2010). The aim of this case series was to present four cases with complicated psychiatric symptomatology and isolated neurologic signs and symptoms, evaluated at a large tertiary medical center and treated for suspected autoimmune encephalitis, demonstrating the complexity of diagnosis and treatment.

Case presentation

Four diagnostically challenging and heterogeneous cases displayed clinical symptomatology suggestive of autoimmune encephalitis. All cases presented with neurologic and psychiatric symptoms, but had negative autoantibody panels, normal or inconclusive magnetic resonance imaging results and non-specific cerebrospinal fluid changes. All were challenged with immunosuppressive/immunomodulatory treatments with overall poor response rates.

Conclusions

There is a heterogeneous presentation of autoimmune encephalitis in pediatric populations. In the absence of positive findings on testing, individuals who do not meet proposed criteria for seronegative encephalitis may be misdiagnosed, and/or may not respond adequately to treatment. In those cases, comprehensive evaluation and stringent application of consensus guidelines is necessary.

Seizures and movement disorders: phenomenology, diagnostic challenges and therapeutic approaches

Seizures and movement disorders (MDs) are distinct neurological conditions presenting with abnormal movements. Despite sharing an overlap in phenomenology, these movements have different origins. In order to explore the overlaps and the narrow boundaries between these two conditions, we performed a review of the literature to explore the risk of seizures in MDs. We discussed the mimics and chameleons including MDs that look like seizure (eg, paroxysmal dyskinesia, status dystonicus) and seizures that look like MDs (eg, epilepsia partialis continua, nocturnal frontal lobe epilepsy). Additionally, we examined the therapeutic challenges as well as the anatomical and chemical pathways relevant in the interplay between epilepsy and MDs. Finally, we proposed an algorithm to guide clinicians towards the final diagnosis of conditions characterised by the co-occurrence of MDs and seizures.

Steroid-responsive Encephalopathy Associated with Autoimmune Thyroiditis (SREAT) Presenting with Pure Cerebellar Ataxia

Background

Myoclonus and tremor are common movement disorder phenomenologies in steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT). Pure ataxia without encephalopathy has rarely been reported.

Case report

We report 21- and 40-year-old females who presented with subacute pure ataxia without encephalopathy. After immunotherapies, both exhibited initial improvement of ataxia, and subsequently remained in plateau phase.

Discussion

This treatable disorder should be added to the differential diagnoses of progressive cerebellar ataxia, and anti-thyroid peroxidase and anti-thyroglobulin should be considered as part of the workup. It is crucial not to misdiagnose SREAT presenting with pure cerebellar ataxia as degenerative or spinocerebellar ataxia.

Evaluation and Management of Autoimmune Encephalitis: A Clinical Overview for the Practicing Child Psychiatrist

Medical conditions that present with psychiatric symptoms are becoming increasingly well-recognized in response to the emergence of the field of neuroimmunology. As the availability of testing for novel antineuronal antibodies has increased, so too has the clinical awareness of this diagnostic spectrum. Psychiatrists may have little exposure to this area of expertise, yet may be called on to assist in the diagnosis and treatment of patients with complex neuropsychiatric syndromes secondary to autoimmune encephalitis. This article summarizes the evaluation and management of patients with autoimmune encephalitis and describes emerging patterns in phenotype recognition.

Neuropsychological impairment in Hashimoto's encephalopathy: A case report and literature review

Hashimoto's encephalopathy (HE) is a rare neurological syndrome characterized by the presence of positive serum antithyroid antibodies, altered mental status, and clinical response to glucocorticoid therapy. Although HE has been documented in the literature from a medical standpoint, reports on the neuropsychological presentation of this syndrome are scarce. This article presents a literature review of cognitive deficits reported in HE cases. In addition, we describe the case of a 76-year-old Russian speaking woman diagnosed with HE in May 2012. MRIs from her disease course and treatment are presented. Posttreatment neuropsychological testing revealed intact attention and construction and impairment in working memory, processing speed, learning, executive functioning, language, and bilateral fine motor dexterity, all of which impacted her functional abilities. Her profile was inconsistent with the typical dementia process. This case demonstrates the utility of neuropsychological assessment for understanding cognitive and functional consequences of HE. The issue of differential diagnosis with dementia is also discussed.

Risks and Benefits of Rituximab in the Treatment of Hashimoto Encephalopathy in Children: Two Case Reports and a Mini Review

Hashimoto encephalopathy is a rare condition, characterized by the association of encephalopathy with a variety of neurological symptoms and autoantibodies to the thyroid gland. Its etiology is unknown, and symptoms are usually treated with immune suppressive therapy, e.g., high doses of corticosteroids.

METHODS AND RESULTS

Here, we report the long-term outcome in two steroid-refractory adolescents with Hashimoto encephalopathy who were treated with rituximab, a monoclonal antibody directed against CD20. In addition, we reviewed the literature regarding treatment strategies in Hashimoto encephalopathy.

CONCLUSIONS

Anti-B-cell therapy can be of value in the treatment of Hashimoto encephalopathy, especially in steroid refractory cases, but side effects due to low levels of immunoglobulins warrant careful monitoring.

The Laboratory Diagnosis of Autoimmune Encephalitis

Autoimmune encephalitis is a group of encephalitis syndromes that cause altered mentality, memory decline, or seizures in association with the presence of serum and cerebrospinal fluid (CSF) autoantibodies (auto-Abs). An early diagnosis enables early treatments. The detection of auto-Abs is a confirmatory diagnosis. Tissue-based assay, cell-based immunoassay, and immunoblotting are used to detect various autoantibodies. The CSF test for the presence of antibodies is important because it is more sensitive and reflects disease activity in many autoimmune encephalitis, although antibody tests can be negative even in the presence of autoimmune encephalitis. EEG is often abnormal, but nonspecific. A unilateral or bilateral medial temporal T2 high signal is a common finding in MRI. Fludeoxyglucose-positron emission tomography is sometimes useful for diagnosis in patients with normal MRI.

Steroid responsive encephalopathy associated with autoimmune thyroiditis (SREAT) presenting as major depression

BACKGROUND

Hashimoto's encephalopathy is a neuropsychiatric disease with symptoms of cognitive impairment, stroke-like episodes, seizures, and psychotic or affective symptoms associated with autoimmune thyroiditis and excellent steroid responsiveness; therefore, it is also called "steroid responsive encephalopathy associated with autoimmune thyroiditis" (SREAT).

CASE PRESENTATION

We present the case of a 50-year-old woman who developed a first-onset depressive syndrome with predominant cognitive impairment and inability to work. Antidepressive treatment and cognitive behavioral therapy over two years were unsuccessful. Neurological examination was unremarkable. Serum analysis showed increased thyroid peroxidase and thyroglobulin antibodies. Cerebrospinal fluid protein and albumin quotient were increased. Magnetic resonance imaging depicted unspecific, supratentorial white matter lesions and frontal accentuated brain atrophy. Electroencephalography was normal. Neuropsychological testing for attentional performance was below average. High-dose intravenous treatment with methylprednisolone over 5 days and oral dose reduction over 3 weeks led to the sustained improvement of clinical symptoms. Following discharge from the hospital, the patient returned to work, and 6.5 months after the start of therapy, no neuropsychological deficit remained.

CONCLUSION

This case report illustrates that SREAT might present with purely depressive symptoms, thus mimicking classical major depression. In such cases, corticosteroid therapy may be an effective treatment option.

Paroxysmal Amnesia Attacks due to Hashimoto's Encephalopathy

Hashimoto's encephalopathy is a rare disease which is thought to be autoimmune and steroid responsive. The syndrome is characterized by cognitive impairment, encephalopathy, psychiatric symptoms, and seizures associated with increased level of anti-thyroid antibodies. The exact pathophysiology underlying cerebral involvement is still lesser known. Although symptoms suggest a nonlesional encephalopathy in most of the cases, sometimes the clinical appearance can be subtle and may not respond to immunosuppressants or immunomodulatory agents. Here we report a case who presented with drowsiness and amnestic complaints associated with paroxysmal electroencephalography (EEG) abnormalities which could be treated only with an antiepileptic drug.

The Diagnosis and Treatment of Autoimmune Encephalitis

Autoimmune encephalitis causes subacute deficits of memory and cognition, often followed by suppressed level of consciousness or coma. A careful history and examination may show early clues to particular autoimmune causes, such as neuromyotonia, hyperekplexia, psychosis, dystonia, or the presence of particular tumors. Ancillary testing with MRI and EEG may be helpful for excluding other causes, managing seizures, and, rarely, for identifying characteristic findings. Appropriate autoantibody testing can confirm specific diagnoses, although this is often done in parallel with exclusion of infectious and other causes. Autoimmune encephalitis may be divided into several groups of diseases: those with pathogenic antibodies to cell surface proteins, those with antibodies to intracellular synaptic proteins, T-cell diseases associated with antibodies to intracellular antigens, and those associated with other autoimmune disorders. Many forms of autoimmune encephalitis are paraneoplastic, and each of these conveys a distinct risk profile for various tumors. Tumor screening and, if necessary, treatment is essential to proper management. Most forms of autoimmune encephalitis respond to immune therapies, although powerful immune suppression for weeks or months may be needed in difficult cases. Autoimmune encephalitis may relapse, so follow-up care is important.

GABAB Encephalitis: A Fifty-Two-Year-Old Man with Seizures, Dysautonomia, and Acute Heart Failure

Autoantibodies to the γ-aminobutyric acid receptor, subtype B (GABAB), are a known cause of limbic encephalitis. The spectrum of clinical manifestations attributable to this antibody is not well defined at the present time. Here we present a case of GABAB encephalitis presenting with encephalopathy, status epilepticus, dysautonomia, and acute heart failure. To our knowledge, heart failure and dysautonomia have not yet been reported with this syndrome.