Clinical and diagnostic aspects of encephalopathy associated with autoimmune thyroid disease (or Hashimoto's encephalopathy)

Hashimoto's Encephalopathy: Case Series and Literature Review

PURPOSE OF REVIEW

To describe the clinical manifestations of Hashimoto's encephalopathy (HE) and discuss its pathogenesis in light of recent research.

RECENT FINDINGS

The pathogenesis of HE is uncertain. Available evidences point towards an autoimmune etiology due to vasculitis or other inflammatory process. Detection of thyroid antibodies - antithyroid peroxidase and anti-thyroglobulin are essential for diagnosis. Autoimmune encephalitis including Anti-IgLON5 disease needs to be excluded in suspected cases with appropriate tests for neuronal surface antibodies. Detection of thyroid autoantibodies is nonspecific, as these can be detected in some normal individuals and in other autoimmune diseases. In recent years, attention has turned to an aggressive form of Hashimoto's thyroiditis accompanied by elevated serum IgG4 levels in younger males with very high levels of thyroid antibodies. The role of the thyroid autoantibodies in the central nervous system (CNS) tissue damage remains unclear and these can act only as markers for diagnosis. Conversely, they have a role to play in determining the thyroid pathology - more glandular fibrosis associated with thyro-peroxidase antibody than with the thyroglobulin antibody. HE is a syndrome characterized by altered mental status, confusion, hallucinations, delusions, and sometimes seizures, in association with high serum anti-thyroid antibody concentration that is usually responsive to glucocorticoid therapy. Diagnosis requires the exclusion of other causes of encephalopathies and encephalitis including autoimmune encephalitis associated with neuronal surface antibodies and paraneoplastic ones. Diagnosis also is dependent on the demonstration of thyroid autoantibodies in serum. Since there is no direct pathophysiologic link between antithyroid antibodies, Hashimoto thyroiditis and the cerebral syndrome, the nomenclature HE could be misleading. The response to steroids led to a renaming of the syndrome to steroid responsive encephalopathy associated with autoimmune thyroiditis (SREAT), though some cases do not respond to steroids. In recent years, attention has turned to an aggressive form of Hashimoto's thyroiditis accompanied by elevated serum IgG4 levels (IgG4-related disease). This is characterized by a higher incidence in men (5:1) than in women, onset at a younger age, more intense thyroid inflammation and higher antithyroid antibody titters. Such patients have excessive production of IgG4 + plasmacytes, which infiltrate various organs leading to their fibrosis and sclerosis, sometimes resulting in inflammatory tumors. HE is treated with corticosteroids along with treatment of the dysthyroid condition, if any. There are yet no guidelines regarding steroid dose and/or duration.

Hashimoto Encephalopathy—Still More Questions than Answers

The normal function of the nervous system is conditioned by the undisturbed function of the thyroid gland and its hormones. Comprehensive clinical manifestations, including neurological disorders in Hashimoto’s thyroiditis, have long been understood and, in recent years, attention has been paid to neurological symptoms in euthyroid patients. Hashimoto encephalopathy is a controversial and poorly understood disease entity and the pathogenesis of the condition remains unclear. We still derive our understanding of this condition from case reports, but on the basis of these, a clear clinical picture of this entity can be proposed. Based on a review of the recent literature, the authors present the current view on the subject, discuss controversies and questions that still remain unanswered, as well as ongoing research in this area and the results of our own work in patients with Hashimoto’s thyroiditis.

Hashimoto's encephalopathy with cerebellar ataxia as the main symptom: A case report and literature review

Hashimoto's encephalopathy (HE), also known as steroid responsive encephalopathy associated with autoimmune thyroiditis (SREAT), has a variety of clinical manifestations, with various neuropsychiatric characteristics, including tremors, transient aphasia, seizures, altered consciousness, myoclonus, cognitive impairment, and psychiatric manifestations. The hallmark presenting feature is a non-specific encephalopathy characterized by alteration of mental status and consciousness ranging from confusion to coma and impaired cognitive function, while those with cerebellar ataxia as the main manifestation is rare. We reported a case of Hashimoto's encephalopathy with cerebellar ataxia as the main manifestation, elevated anti-thyroid antibodies (anti-TPO/TG), and normal thyroid function. The symptoms of cerebellar ataxia improved after steroid treatment. Meanwhile, we reviewed the clinical features of 20 representative cases of HE with cerebellar ataxia as the core symptoms. In conclusion, based on our case findings and literature review, the diagnosis of HE should be suspected in cases of encephalopathy without an obvious cause, to quickly start an effective treatment.

Complexities of cooccurrence of catatonia and autoimmune thyroiditis in bipolar disorder: A case series and selective review

In recent years the neurobiological underpinnings of catatonia have been an emerging area of interest. Catatonia is frequently encountered in mood disorders, neurological disorders and systemic illnesses. Furthermore, the manifestation of catatonia in autoimmune disorders such as NMDA receptor antibody encephalitis and thyroiditis reinforces its neuropsychiatric nature. Irrespective of cause benzodiazepines and electroconvulsive therapy remain the standard treatments for catatonia, although a proportion fail to respond to the same. This report describes three women with pre-existing bipolar disorder presenting in catatonia. Interestingly in all three, while benzodiazepines and electroconvulsive therapy failed, a dramatic resolution of catatonia with corticosteroids was noted following the detection of Hashimoto's thyroiditis. Hashimoto's encephalopathy presenting as catatonia has been reported, but our patients' profile differed in having had an a priory diagnosis of bipolar disorder. Given that both catatonia and thyroid dysfunction are frequently encountered in bipolar disorder, Hashimoto's encephalopathy as a potential cause for this concurrent manifestation in bipolar disorder may be overlooked. Therefore, it is essential to suspect Hashimoto's encephalopathy when catatonia manifests in bipolar disorder. A timely evaluation would be prudent as they may fail to respond to standard treatments for catatonia but respond remarkably to corticosteroids, saving much time and angst. Recent evidence implicates immune system dysfunction, with neuroinflammation and peripheral immune dysregulation contributing to the pathophysiology of bipolar disorder as well as catatonia. Findings from this study reaffirm the role of immune system dysfunction common to the etiopathogenesis of all these disorders, highlighting the complex interplay between catatonia, thyroiditis and bipolar disorder.

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Catatonia is common in bipolar disorder and also noted in autoimmune disorders.

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Thyroiditis in bipolar disorder may be overlooked due to frequent occurrence of thyroid dysfunction.

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Catatonia in bipolar disorder may result from Hashimoto's encephalopathy.

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Hashimoto's related catatonia in bipolar disorder may poorly respond to standard treatment.

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Autoimmune thyroiditis and catatonia highlight the immune dysfunction hypothesis of bipolar disorder.

Psychiatric Presentations Heralding Hashimoto's Encephalopathy: A Systematic Review and Analysis of Cases Reported in Literature

Hashimoto's encephalopathy (HE) may often present initially with psychiatric symptoms. These presentations are often variable in clinical aspects, and there has been no systematic analysis of the numerous psychiatric presentations heralding an eventual diagnosis of HE which will guide clinicians to make a correct diagnosis of HE. This systematic review was done to analyze the demographic characteristics, symptom typology, and clinical and treatment variables associated with such forerunner presentations. Electronic databases such as PubMed, ScienceDirect, and Google Scholar databases were searched to identify potential case reports that described initial psychiatric presentations of HE in English language peer-reviewed journals. The generated articles were evaluated and relevant data were extracted using a structured tool. We identified a total of forty articles that described 46 cases. More than half of the total samples (54.4%) were above the age of 50 years at presentation. The most common psychiatric diagnosis heralding HE was acute psychosis (26.1%) followed by depressive disorders (23.9%). Dementia (10.9%) and schizophrenia (2.2%) were uncommon presentations. Antithyroid peroxidase antibodies were elevated in all patients but not antithyroglobulin antibodies. Preexisting hypothyroidism was absent in majority of cases (60.9%). Steroid doses initiated were 500-1000 mg of intravenous methylprednisolone for majority (52.1%) of patients while oral steroid maintenance was required for a significant minority (39.1%). Psychiatric manifestations of HE may be heterogeneous and require a high index of clinical suspicion, especially in older adults. A range of clinical and treatment variables may assist clinicians in making a faster diagnosis and instituting prompt and effective management.

Autonomic alterations as a clinical manifestation of encephalopathy associated with autoimmune thyroid disease

Encephalopathy associated with autoimmune thyroid disease (EAATD), also known as Hashimoto's encephalopathy, is a rare neurological condition that may occur in patients with clinical or sub-clinical autoimmune thyroid disease. The pathogenesis of EAATD has been not clearly elucidated yet. The diagnostic criteria include neurological or psychiatric symptoms, high levels of anti-thyroid antibodies, and exclusion of other possible causes of encephalopathy. In the large majority of cases, EAATD patients respond to immunosuppressant therapies, in particular to corticosteroids. We report the case of a patient with Hashimoto's thyroiditis and recurrent manifestations of encephalopathy over the previous few years responding to corticosteroid treatment. The patient presented with language and cognitive impairment, ataxia, and neurovegetative/autonomic symptoms. She was euthyroid with mildly raised anti-thyroid peroxidase antibodies. An extensive diagnostic work-up, including electroencephalogram, brain magnetic resonance, hormonal assessment, and an exhaustive panel of antibodies possibly associated with autoimmune encephalopathy, was carried out and excluded other possible etiologies of encephalopathy. The diagnosis of EAATD possibly affecting the hypothalamus and/or the neurovegetative regulatory centers was made and treatment with prednisolone was timely commenced with a dramatic and rapid improvement with progressive normalization of the symptoms. To the best of our knowledge, this is the first report of neurovegetative/autonomic alterations in the setting of EAATD.

Hashimoto's encephalopathy presenting as pseudobulbar palsy

INTRODUCTION

Hashimoto's encephalopathy (HE) is an autoimmune condition with varied neurological and psychiatric features. HE is very unusual as a cause of pseudobulbar palsy (PSP).

CASE PRESENTATION

A 14-year-old male was admitted with right-sided weakness, dysphagia, speech disorder, and aggressiveness. Brain magnetic resonance imaging showed increased intensity in bilateral temporal, insular cortex, amygdala, and parahippocampal area on T2-weighted and fluid-attenuated inversion recovery images. Autoimmune encephalitis was considered as the patient had subacute onset of psychiatric and motor disturbances with normal findings for cerebrospinal fluid. N-methyl-D-aspartate receptor, anti-glutamate-type α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid 1 and 2, anti-contactin-associated protein-like 2, anti-gamma-aminobutyric acid receptor, anti-Leucine-rich, and glioma-inactivated 1 antibodies were negative but the anti-thyroperoxidase (antiTPO) level was greater than 998 IU/ML (n:0-9). Steroid therapy was initiated as pulse therapy and maintained with 2-mg/kg/day dose with the diagnosis of HE. He was symptom free for 6 months. In the follow-up period, he had two recurrences which responded to steroid therapy.

CONCLUSION

The common causes of PSP are demyelinating, vascular, and motor neuron diseases and congenital malformations of the opercular or insular cortex. However, there are no cases of PSP developing after any autoimmune encephalitis. This case highlights the importance of early detection of antiTPO antibodies with the findings of PSP due to autoimmune encephalitis.

A novel assessment and treatment approach to patients with Hashimoto's encephalopathy

Hashimoto's encephalopathy (HE) is rarely reported with only a few hundred cases published. Diagnosis is made in patients with an appropriate clinical picture and high antithyroperoxidase (anti-TPO) antibodies after infectious, toxic and metabolic causes of encephalopathy have been excluded. There is little objective data on the neurocognitive impairment in patients with HE and their improvement with treatment. We present the case of a 28-year-old woman with HE. Approach to management was novel as objective neuropsychological assessment was used to assess her clinical condition and response to treatment. Intravenous immunoglobulin (IVIg) as the first-line treatment instead of steroids. She responded well. The case illustrates that a different approach is required for the diagnosis and treatment of HE. A new diagnostic criteria is proposed that includes neurocognitive assessment, serum and CSF antibodies, an abnormal EEG and exclusion of other causes of encephalopathy. Furthermore, treatment should be tailored to the patient.

LEARNING POINTS

Neurocognitive assessment should be carried out to assess the extent of brain involvement in suspected Hashimoto's encephalopathy pre- and post- treatment.Treatment of Hashimoto's encephalopathy should be tailored to the patient.Unifying diagnostic criteria for Hashimoto's encephalopathy must be established.

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.

Hashimoto's Encephalopathy Presenting with Unusual Behavioural Disturbances in an Adolescent Girl

Hashimoto's encephalopathy (HE) is a rare autoimmune disorder with neurological and neuropsychiatric manifestations and elevated titres of anti-thyroid antibodies. Here we are reporting a case of HE in a 19-year-old girl who presented with seizure-like episodes, confusion, and behavioural disturbances with catatonic symptoms such as posturing, echopraxia, echolalia, and ambivalence. Patient did not respond to antipsychotics and anticonvulsants. On further investigation, patient was found to have high serum anti-TPO antibodies of about 1261 U/mL with euthyroid status, which supported a suspicion of HE. Our consultant neurologist confirmed the diagnosis and she was started on injection of methylprednisolone 750 mg OD. Since patient started showing clinical improvement, her antipsychotic medications were tapered off. On follow-up, patient has recovered and is functioning well. Since HE is a diagnosis of exclusion, very high anti-TPO antibodies and good response to steroids supported the diagnosis of HE in this patient after excluding other etiological possibilities. This case has been reported because the clinical presentation was predominantly neurobehavioural manifestations which is uncommon with HE.

Thyroid dysfunction in children with autism spectrum disorder is associated with folate receptor α autoimmune disorder

Folate receptor α (FRα) autoantibodies (FRAAs) are prevalent in autism spectrum disorder (ASD). FRAAs disrupt folate transport across the blood-brain barrier by binding to the FRα. Thyroid dysfunction is frequently found in children with ASD. We measured blocking and binding FRAAs and thyroid-stimulating hormone (TSH), free thyroxine (T4) (FT4), total triiodothyronine (T3) (TT3), reverse T3 (rT3), thyroid-releasing hormone (TRH) and other metabolites in 87 children with ASD, 84 of whom also underwent behaviour and cognition testing and in 42 of whom FRAAs, TSH and FT4 were measured at two time points. To better understand the significance of the FRα in relation to thyroid development, we examined FRα expression on prenatal and postnatal thyroid. TSH, TT3 and rT3 were above the normal range in 7%, 33% and 51% of the participants and TRH was below the normal range in 13% of the participants. FT4 was rarely outside the normal range. TSH concentration was positively and the FT4/TSH, TT3/TSH and rT3/TSH ratios were inversely related to blocking FRAA titres. On repeated measurements, changes in TSH and FT4/TSH ratio were found to correspond to changes in blocking FRAA titres. TSH and the FT4/TSH, TT3/TSH and rT3/TSH ratios were related to irritability on the Aberrant Behavior Checklist and several scales of the Social Responsiveness Scale (SRS), whereas TT3 was associated with SRS subscales and TRH was related to Vineland Adaptive Behavior Scale subscales. The thyroid showed significant FRα expression during the early prenatal period, although expression decreased significantly in later gestation and postnatal thyroid tissue. The results of the present study suggest that thyroid dysfunction in ASD may be related to blocking FRAA. The high expression of FRα in the early foetal thyroid suggests that foetal and neonatal exposure to maternal FRAAs could affect the development of the thyroid and may contribute to the pathology in ASD.

Hashimoto's encephalitis associated with AMPAR2 antibodies: a case report

BACKGROUND

Hashimoto's encephalitis (HE) is a rare neurological complication of Hashimoto's thyroiditis (HT), while limbic encephalitis (LE) is an autoimmune inflammatory disorder frequently associated with anti-neuronal antibodies. The glutamate receptor α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAR) is important for synaptic transmission, memory, and learning. The etiology of HE remains unclear. We present a case of HE with antibodies to AMPAR2 both in the serum and cerebrospinal fluid.

CASE PRESENTATION

The patient presented with progressive memory loss and subsequently went into a coma. Magnetic resonance imaging revealed temporal lobe and hippocampal lesions, while the electrocardiogram showed paroxysmal delta waves. Elevated serum levels of antibodies against thyroid globulin, thyroid peroxidase, and thyroid stimulating receptor were also noted. Ultrasonography showed enlargement of the thyroid gland. Therefore, the diagnosis was established as HE. Both the CSF and serum samples of the patient tested positive for antibodies to the cell-surface antigen AMPAR2. Intravenous injection of immunoglobulin followed by dexamethasone treatment resulted in recovery from the coma. Follow-up examination three months later showed some improvement of memory. To our knowledge, this is the first report on the detection of AMPAR2 antibodies in HE.

CONCLUSIONS

Our findings suggest that antibodies to AMPAR2 may be involved in the pathogenesis of HE. Elevated levels of thyroid antibodies possibly cause immune dysfunction, leading to the production of anti-AMPAR2 antibodies that are detrimental to the neurons. We believe that encephalitis patients with thyroid abnormalities should undergo screening for anti-neuronal antibodies, and early immune therapy may improve prognosis.

Encephalopathy Associated with Autoimmune Thyroid Disease: A Potentially Reversible Condition

Autoimmune thyroid disease may occasionally associate with unspecific neurological symptoms, which are more commonly insidious, include cognitive or behavioural symptoms, and may associate with tremor, myoclonus, or ataxia. We report a 61-year-old female patient who presented with chronic headache, insidious mood, and cognitive disturbance which evolved in a few months to dementia associated with exuberant limb myoclonus. Diagnostic workup revealed high anti-thyroid peroxidase antibody titers and an inflammatory CSF profile, and it was negative for other possible etiologies. Treatment with steroids induced significant improvement. The diagnosis of encephalopathy associated with autoimmune thyroid disease is still controversial given the fact that the clinical presentation and diagnostic workup are unspecific, the pathophysiology is still undetermined, and the diagnosis is mostly of exclusion. No direct correlation is found between anti-thyroid antibody titers and clinical presentation, and it is currently speculated that other still unrecognized antibodies may be responsible for this clinical entity. It is extremely important to recognize this entity because it is potentially treatable with immunotherapies. It is also increasingly recognized that clinical improvement with first-line treatment with steroids may be absent or incomplete, and other immunotherapies as immunosuppressants, intravenous immunoglobulin, or plasma exchange must be attempted in the clinical suspicion of EEAT.

Thyroid Autoantibody Positive Anti-N-Methyl-D-Aspartate Receptor Encephalitis

Background

Hashimoto's encephalopathy (HE) and anti N-methyl-D-aspartate receptor (NMDAR) encephalitis have clinical overlaps.

Case Report

A 70-year-old woman presented with acutely developed confusion, disorientations and psychosis. HE was suspected based on goiter, markedly elevated anti-thyroglobulin and anti-thyroid peroxidase antibody. She was placed on high dose steroid and intravenous immunoglobulins administration, which did not ameliorate her symptoms. After the antibodies to the NMDAR were identified, weekly 500 mg of rituximab with 4 cycles were started. The current followed up indicated a complete recovery.

Conclusions

The possible associations between NMDAR antibody and autoimmune thyroid antibodies in anti-NMDAR encephalitis with positive thyroid autoantibodies remain unclear. However, a trend toward a higher incidence of NMDAR antibody in patients with autoimmune thyroid antibodies than without has been observed. Cases of encephalitis with only NMDAR antibody (pure anti-NMDAR encephalitis) also occur. Therefore, it is important for clinicians to know the clinical and pathogenic differences between anti-NMDAR encephalitis with positive thyroid autoantibody and pure anti-NMDAR encephalitis for relevant treatment, predicting prognosis, and future follow-up.

Hashimoto's encephalopathy: A rare proteiform disorder

Hashimoto's encephalopathy (HE) is a rare not well understood, progressive and relapsing multiform disease, characterized by seizures, movement disorders, subacute cognitive dysfunction, psychiatric symptoms and responsiveness to steroid therapy. The disorder is generally associated with thyroid diseases and the most common feature is the presence of anti-thyroperoxidase antibodies (TPOAb). Patients are usually euthyroid or mildly hypothyroid at presentation. All age groups can be affected. The pathophysiology is still unclear, especially the link between elevated serum TPOAb and the encephalopathy. Most reported cases occurred in women and girls. Unspecific symptoms, non-pathognomonic laboratory neurophysiology and neuroimaging features make its diagnosis a real challenge for clinicians. The case of a 16 year old boy, with a clinical picture of HE associated with hypothyroidism, demonstrating an excellent response to high dose steroids is presented together with a systematic review of the literature.

The use of cerebrospinal fluid and neuropathologic studies in neuropsychiatry practice and research

The gold standard for diagnosis of neurodegenerative diseases (ie, Alzheimer disease, frontotemporal dementia, Parkinson disease, dementia with Lewy bodies, amyotrophic lateral sclerosis) is neuropathologic examination at autopsy. As such, laboratory studies play a central role in antemortem diagnosis of these conditions and their differentiation from the neuroinflammatory, infectious, toxic, and other nondegenerative etiologies (eg, rapidly progressive dementias) that are encountered in neuropsychiatric practice. This article summarizes the use of cerebrospinal fluid (CSF) laboratory studies in the diagnostic evaluation of dementia syndromes and emerging CSF biomarkers specific for underlying neuropathology in neurodegenerative disease research.

Hashimoto's encephalopathy: a brief review

Hashimoto's encephalopathy (HE) is a syndrome of altered mental status, hallucinations, delusional thinking, and often, epileptic seizures. It is diagnosed by the clinical syndrome, the presence of elevated titers of antithyroid antibodies, the lack of another diagnosis based on clinical evaluation, and the response to corticosteroid and other immunosuppressant treatment. This review discusses the symptoms, pathophysiology, and treatment of HE. The disorder is important to recognize because aggressive treatment may bring about a favorable clinical outcome. The disorder has a relatively benign prognosis, compared with many of the entities for which it can be mistaken.

Brain hypoperfusion on Tc-99m-ethylene dicysteine diethyl ester single-photon emission computed tomography in Hashimoto's encephalopathy

We present a 17-year-old female, previously diagnosed of autoimmune hyperthyroidism who had an acute neurological episode and presented high antithyroid antibodies titers, cerebral spinal fluid and electroencephalogram changes. Tc-99m ethylene dicysteine diethyl ester brain single-photon emission computed tomography (SPECT) showed global and patchy hypoperfusion. With glucocorticoid therapy, clinical symptoms disappeared; there was a decrease in antithyroid antibody levels and repeat brain SPECT revealed improvement of perfusion.

Diagnostic and therapeutic aspects of Hashimoto's encephalopathy

OBJECTIVE

To share our experience on clinical presentation and management of patients diagnosed with Hashimoto's Encephalopathy (HE) at Vanderbilt Medical Center between 1999 and 2012.

BACKGROUND

HE is a rare disorder characterized by encephalopathy and central nervous system (CNS) dysfunction, elevated antithyroid antibodies, the absence of infection or structural abnormalities in the CNS, and a response to treatment with steroids. The relationship between thyroid antibodies and encephalopathy has remained unresolved.

DESIGN/METHODS

Retrospective chart review.

RESULTS

We identified 13 patients who met the criteria for the diagnosis of HE. The median age was 49 years (range, 2-66) and all except one were women. Encephalopathy in the form of altered mental status, stroke-like symptoms or seizures, with prompt resolution of symptoms upon receiving steroids, was the commonest presentation, seen in 7 patients. The second commonest presentation was subacute progressive decrease in cognitive function, which reversed within days to weeks after steroid therapy, seen in 4 patients. Electroencephalogram (EEG) was available in 12 patients and was abnormal in 8, showing nonspecific cerebral dysfunction in all 8 and epileptiform activity in 3. Treatment consisted of steroids in the acute phase for 12 of 13 patients with rapid improvement in symptoms. Maintenance therapy was rituximab in 7 patients, intravenous immunoglobulin (IVIg) in 7, azathioprine in 4, mycophenolate mofetil in 3, and methotrexate in 1 (some patients received sequential therapy with different agents). There was complete or near complete resolution of symptoms in 12 of the 13 patients.

CONCLUSIONS

We present a cohort of patients in whom CNS dysfunction was associated with elevated antithyroid antibodies and reversal of disease followed immunomodulatory therapies.

Cognitive impairments in Hashimoto's encephalopathy: a case-control study

Background/Aims

Hashimoto's encephalopathy is considered as a treatable dementia, but it is often misdiagnosed. We investigated cognitive impairment and the MRI pathology of Hashimoto's encephalopathy patients.

Methods

The study comprised eight patients with Hashimoto's encephalopathy, 16 patients with mild Alzheimer’s disease and 24 healthy subjects. A neuropsychological battery included assessments of memory, language, attention, executive function and visuospatial ability. Cranial MRI was obtained from all Hashimoto's encephalopathy patients.

Results

Hashimoto's encephalopathy and mild Alzheimer’s disease showed cognitive impairments in episodic memory, attention, executive function and visuospatial ability, but naming ability was unaffected in Hashimoto's encephalopathy. The MRI of Hashimoto's encephalopathy showed leukoencephalopathy-like type or limbic encephalitis-like type; the lesions did not affect the temporal cortex which plays a role in naming ability.

Conclusion

Except that the naming ability was retained, the impairments in cognitive functions for the Hashimoto's encephalopathy patients were similar to those of Alzheimer’s disease patients. These results were consistent with the MRI findings.

Graves' disease presenting with catatonia: a probable case of encephalopathy associated with autoimmune thyroid disease

Bharadwaj B, Sugaparaneetharan A, Rajkumar RP. Graves' disease presenting with catatonia: a probable case of encephalopathy associated with autoimmune thyroid disease.

Introduction: Encephalopathy associated with autoimmune thyroid disease (EAATD) is diagnosed when neuropsychiatric symptoms of acute or sub-acute onset occur along with clinical or subclinical autoimmune thyroid dysfunction. Supporting evidence includes the presence of anti-thyroid antibodies in the serum and/or cerebrospinal fluid. The thyroid hormone alteration is not sufficient to explain the neuropsychiatric manifestations. The most commonly described electroencephalographic abnormality in this condition is a generalised background slowing. Clinical descriptions of EAATD have focused mainly on neurological symptoms including seizures, loss of consciousness, myoclonus and cognitive symptoms.

Case: We present the case of a 48-year-old lady who presented with catatonia. Her clinical and laboratory features were suggestive of Graves' disease which was hitherto undiagnosed. Anti-thyroid antibodies were positive. Electroencephalogram showed a brief period of temporal delta activity. The findings are suggestive of EAATD. Differential diagnoses of metabolic derangements like electrolyte imbalance, hepatic and renal failure, neuroinfections and psychiatric conditions like acute psychosis were ruled out.

Discussion: Treatment involves a course of corticosteroids. Response to corticosteroids, however, is not essential for the diagnosis of EAATD as the patient may respond to symptomatic treatment alone as in our case. Outcomes reported in case series have been generally good as in our patient.

Conclusion: This report illustrates the need to keep a high index of suspicion for an organic aetiology in cases presenting with catatonia. A thorough neuropsychiatric evaluation is useful in such cases. In patients with severe neuropsychiatric manifestations associated with thyroid disease, an autoimmune thyroid disease should be considered as a possibility.

Hashimoto's thyroiditis in patients with normal thyroid-stimulating hormone levels

Hashimoto's thyroiditis (HT) is one of the most common autoimmune endocrine disorders and often leads to hypothyroidism. It has been shown to substantially affect a patient's quality of life. Associated conditions and diseases were thought to be attributable to hypothyroidism. Yet, many patients still suffer from various symptoms even though all thyroid parameters are within the normal range. Independently of thyroid gland function, HT is associated with a wide range of organ-specific and non-organ-specific autoimmune disorders, as well as other diseases, including neuropsychological/psychiatric deficits, decreased left ventricular performance, disorders of the gut, fibromyalgia and reproductive health issues, among others. The underlying pathomechanisms remain unclear. Future treatment options might include thyroidectomy, selenium administration, prophylactic levothyroxine supplementation and dehydroepiandrosterone. However, further research is warranted to clarify the main pathophysiologic implications of thyroid autoimmunity and also to establish treatment options for euthyroid patients who suffer from HT-related symptoms and diseases.

Hashimoto encephalopathy causing drug-resistant status epilepticus treated with plasmapheresis

Hashimoto encephalopathy is a rare, clinically heterogenous condition. Its treatment is based on corticosteroids. A previously normal 12-year-old boy was admitted to our pediatric emergency department with status epilepticus. He experienced a recurrence of status epilepticus after pentobarbital withdrawal, and required repeated resumptions of drug-induced coma. He manifested acute personality changes. His limbic encephalitis markers were normal, but his level of anti-thyroid peroxidase antibody was high. A diagnosis of Hashimoto encephalopathy was considered. Our patient responded to plasmapheresis instead of corticosteroid treatment. This case report is the first, to the best of our knowledge, of plasmapheresis because of Hashimoto encephalopathy in a child.

Encephalopathy associated with autoimmune thyroid disease (Hashimoto's thyroiditis) presenting as depression: a case report

Encephalopathy associated with autoimmune thyroid disease (EAATD) is a rare condition associated with Hashimoto's thyroiditis or Graves' disease. It is often underdiagnosed because of the various clinical presentations and lack of widely accepted diagnostic criteria. We report a 46-year-old man who presented with an acute depressive episode and was proven to have encephalopathy associated with Hashimoto's thyroiditis. The exclusive psychiatric manifestations of this case called our attention to the fact that an improved awareness of EAATD in patients with a history of thyroid disease can lead to a timely diagnosis and excellent disease prognosis.

Steroid-responsive encephalopathy in autoimmune thyroiditis: Clinical spectrum and MRI observations in three cases

Hashimoto's encephalopathy (H.E.) is probably of autoimmune etiology, and manifests with seizures, stroke-like episodes, cognitive decline, neuropsychiatric symptoms, myoclonus. It is presumed to be autoimmune in origin with high serum titers of antithyroid peroxidase antibodies (anti-TPA). Thyroid function might often be normal. The diagnosis is arrived at by excluding other toxic, metabolic and infectious causes of encephalopathies, supportive clinical profile, elevated thyroid antibodies and optimum steroid response. We present the characteristic phenotypic manifestations, magnetic resonance imaging and electroechography observations and response to immunomodulation with follow-up in three cases of H.E. All the three cases manifested with subacute to chronic progressive encephalopathy, cerebellar dysfunction, seizures, behavioral abnormalities and oculomotor disturbances and had evidence of hypothyroidism, elevated titers of anti-TPA and positive thyroid anti-microsomal antibodies. Atypical and uncommon presentations are known. This report emphasizes that a high index of suspicion is often required in cases with “investigation negative encephalopathy” for early diagnosis of H.E.

Paediatric Hashimoto encephalopathy, refractory epilepsy and immunoglobulin treatment - unusual case report and review of the literature

BACKGROUND

 Hashimoto encephalopathy (HE) is a rare autoimmune disorder. It is defined as a 'corticosteroid-responsive encephalopathy associated with thyroiditis'.

CLINICAL OBSERVATION

  We describe a boy who suffered from HE, responded only to intravenous immunoglobulin therapy. This is the first case report of immunoglobulin therapy in paediatric HE.

CONCLUSION

 After review of the literature, we recommend that unexplained encephalopathy in children should lead to evaluation of thyroid autoantibody titres. Immunoglobulins should be considered.

[A 66-year-old woman with confusion, aphasia, and myoclonus]

BACKGROUND

Hashimoto's encephalopathy, also called steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), is a rare syndrome with an unknown pathogenesis. Clinical onset is insidious or acute with variable neurological symptoms. Spinal protein is elevated in most cases, but findings are non-specific in routine blood tests and on cerebral CT and EEG. The most important diagnostic clue is elevated levels of thyroid antibodies, especially anti-thyroid peroxidase antibody (anti-TPO). Administration of corticosteroids is the treatment of choice and usually results in complete recovery.

CASE REPORT

A 66-year-old woman had experienced episodic neurological symptoms over a few weeks. On admission she demonstrated moderate aphasia, tremor and myoclonus, but no other focal neurological signs. A cerebral CT scan and routine blood tests did not provide diagnostic clues. The cerebrospinal fluid protein level was markedly elevated, and treatment with antibiotic and antiviral agents against possible encephalitis was started. However, the clinical condition did not improve. Further testing showed elevated levels of anti thyroxine peroxidase (aTPO) antibodies. Based on this finding, and after exclusion of other causes, the patient was diagnosed with Hashimoto's encephalitis. On treatment with systemic steroids, the clinical condition improved over a few days.

CONCLUSION

Hashimoto's encephalitis is a rare syndrome. Still, it is important to diagnose patients correctly. Treatment with steroids induces marked clinical improvement and usually confers a good prognosis.

Encephalopathy associated with autoimmune thyroid disease in patients with Graves' disease: clinical manifestations, follow-up, and outcomes

Background

The encephalopathy associated with autoimmune thyroid disease (EAATD) is characterized by neurological/psychiatric symptoms, high levels of anti-thyroid antibodies, increased cerebrospinal fluid protein concentration, non-specific electroencephalogram abnormalities, and responsiveness to the corticosteroid treatment in patients with an autoimmune thyroid disease. Almost all EAATD patients are affected by Hashimoto's thyroiditis (HT), although fourteen EAATD patients with Graves' disease (GD) have been also reported.

Methods

We have recorded and analyzed the clinical, biological, radiological, and electrophysiological findings and the data on the therapeutic management of all GD patients with EAATD reported so far as well as the clinical outcomes in those followed-up in the long term.

Results

Twelve of the fourteen patients with EAATD and GD were women. The majority of GD patients with EAATD presented with mild hyperthyroidism at EAATD onset or shortly before it. Active anti-thyroid autoimmunity was detected in all cases. Most of the patients dramatically responded to corticosteroids. The long term clinical outcome was benign but EAATD can relapse, especially at the time of corticosteroid dose tapering or withdrawal. GD and HT patients with EAATD present with a similar clinical, biological, radiological, and electrophysiological picture and require an unaffected EAATD management.

Conclusions

GD and HT equally represent the possible background condition for the development of EAATD, which should be considered in the differential diagnosis of all patients with encephalopathy of unknown origin and an autoimmune thyroid disease, regardless of the nature of the underlying autoimmune thyroid disease.

Headache attributed to infections nosography and differential diagnosis

Headache is a very frequent symptom of infection. It has many possible underlying mechanisms, of which two or more can coexist in a single patient. It can be caused by direct stimulation of intracranial pain-producing structures, as in the case of brain abscesses, by irritation of the pachy- and leptomeninges, as in cases of bacterial or viral meningitis, or by a state of intracranial hypertension, as seen in obstructive hydrocephalus. There is no doubt that headache is often the first or the predominant symptom of serious, sometimes life-threatening, infectious diseases; certainly, it is a condition frequently encountered in all epidemiological studies. Indeed, it is estimated that over 60% of people have, at some point in their lives, experienced headache during an infection. This evidence leads to the need for a systematic approach to headache secondary to infection. This chapter provides some elements on pain mechanisms in systemic and intracranial infections and on the possible role of antimicrobial agents in the genesis of headache. The first section provides a detailed "etiology-based" description of the International Classification of Headache Disorders, 2nd edition (ICHD-II: Headache Classification Subcommittee of the International Headache Society, 2004), while the second section presents a "symptom-based" algorithm applicable in the first diagnostic assessment, according to the headache features and to the most frequently associated clinical manifestations during infections of the central nervous system (CNS).

Hashimoto encephalopathy: Neurological and psychiatric perspective

Hashimoto encephalopathy (HE) is an autoimmune disease with neurological and neuropsychiatric manifestations and elevated titers of antithyroid antibodies in serum and cerebrospinal fluid. Patients are mostly women. Age varies from 8 to 86 years. Prevalence of HE is estimated to be 2.1/100,000. Neurological and/or psychiatric symptoms and signs constitute the clinical picture. The disease responds well to corticosteroid therapy, but sometimes other immunomodulatory therapies must be applied. Autoimmune mechanisms with antibodies against antigens in the brain cortex are suspected. The course of the disease can be acute, subacute, chronic, or relapsing/remitting. Some patients improve spontaneously, but a few died in spite of adequate therapy.

A case of autoimmune thyroid disease presenting posterior reversible encephalopathy syndrome

A 40-year-old woman was admitted to our hospital with disturbance of consciousness and seizure. We diagnosed encephalopathy associated with autoimmune thyroid disease (EAATD). Fluid-attenuated inversion recovery and diffusion-weighted MRI demonstrated hyperintense lesions in the left occipitotemporal lobe on admission, but these findings disappeared on day 11 without neurological deficits, compatible with posterior reversible encephalopathy syndrome (PRES). We report here this case of autoimmune thyroid disease presenting as PRES.