Time course of Hashimoto's encephalopathy revealed by MRI: Report of two cases

Hashimoto encephalopathy: a literature review and case report with comprehensive neuropsychological evaluation

Objective: Hashimoto's encephalopathy (HE), a rare immune-mediated disorder, manifests as altered mental state, cognitive and psychological dysfunction, seizures, and myoclonus. Little is known, however, about the neuropsychological profiles of individuals with HE due to the sparse amount of research. This report overviews HE, summarizes findings from available published neuropsychological evaluations, and details neuropsychological examinations of a 57-year-old White woman with a confirmed HE diagnosis evidencing persistent neuropsychological impairment at two discrete timepoints. Method: An extensive literature search was conducted on PubMed and Google Scholar for studies including neuropsychological evaluations of HE cases. Our neuropsychological evaluation included chart review, diagnostic clinical interview, performance-based neurocognitive assessment, and measures of personality and psychopathology. Results: Our assessment revealed a largely subcortical pattern of neurocognitive impairment and impactful neuropsychiatric symptoms that, together, significantly impacted the patient's quality of life and functional status. The patient's performance improved during a six-month re-evaluation within the domains of cognition, psychological functioning, and functional independence. Conclusions: This article highlights the complexity and possible long-term sequela of HE. Complex medical history (including autoimmune disorders) and psychiatric presentation at onset may be factors related to longer-term cognitive dysfunction. Neuropsychology and psychology can serve important and unique roles in assessing long-term functioning and response to treatment in such cases.

Steroid-Responsive Encephalopathy Associated With Autoimmune Thyroiditis Presenting With Parkinsonism

Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT) is a rare condition defined as encephalopathy with a positive antithyroid antibody. We report the case of a 52-year-old woman who presented with Parkinsonism associated with Hashimoto's thyroiditis. A few similar cases have been reported. Our patient responded well to corticosteroids with a significant reduction in symptoms. Diagnosis can pose a significant challenge in SREAT cases because of its variable clinical presentation. Therefore, we recommend evaluating thyroid function and thyroid autoantibodies in the context of acute and subacute encephalopathy. In the elderly population, SREAT, as a cause of Parkinsonism, should not be forgotten because of its simple treatment and significant improvements in neurological symptoms.

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.

Relationship between thyroid hormones and central nervous system metabolism in physiological and pathological conditions

Thyroid hormones (THs) play an important role in the regulation of energy metabolism. They also take part in processes associated with the central nervous system (CNS), including survival and differentiation of neurons and energy expenditure. It has been reported that a correlation exists between the functioning of the thyroid gland and the symptoms of CNS such as cognitive impairment, depression, and dementia. Literature data also indicate the influence of THs on the pathogenesis of CNS diseases, such as Alzheimer's disease, epilepsy, depression, and Parkinson's disease. This review describes the relationship between THs and metabolism in the CNS, the effect of THs on the pathological conditions of the CNS, and novel options for treating these conditions with TH derivatives.

A Case of Euthyroid Steroid-Responsive Encephalopathy With Subacute Dementia

Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), frequently termed as Hashimoto's encephalopathy (HE), is characterized by reversible encephalopathy with the presence of elevated antithyroid antibodies. The condition was initially described due to its association with Hashimoto's thyroiditis. We report a case of euthyroid HE presenting as subacute dementia. A 50-year-old woman presented with progressive memory decline for six weeks. Thyroid function tests, thyroid ultrasound, and cerebrospinal fluid analysis were unremarkable. Electroencephalogram showed generalized slowing with triphasic waves. On magnetic resonance imaging, T1 weighted images revealed hyperintensity in bilateral basal ganglia. Antithyroglobulin and antithyroid peroxidase were markedly elevated. She improved remarkably on tablet prednisolone 60 mg once daily, confirming the suspicion of steroid-responsive encephalopathy. Thus, we conclude that patients with subacute cognitive decline could be screened for antithyroid antibodies in the dementia workup despite their euthyroid status.

MRI Findings of Two Patients With Hashimoto Encephalopathy

Hashimoto encephalopathy (HE), also known as steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), is a rare type of autoimmune encephalitis that typically presents with cognitive and neuropsychiatric symptoms that resolve with steroids. Positive neuroimaging findings of HE are rarely reported in the literature. We present two cases of HE with abnormal MRI findings, including signal abnormalities in the claustrum, cerebral white matter, and mesial temporal lobes. HE and other forms of autoimmune encephalopathies can often be misdiagnosed as viral encephalopathies. As such detection of subtle neuroimaging findings in the context of suspicious clinical history should prompt further investigations to ensure accurate and timely diagnosis.

Brain Diffusion Tensor Imaging Findings in Hashimoto's Thyroiditis

BACKGROUND AND PURPOSE

Hashimoto's thyroiditis (HT) is a type of autoimmune thyroid disease. Diffusion tensor imaging (DTI) can evaluate microstructural brain involvement in various diseases. We aimed to investigate whether there were any DTI differences in patients with HT, and the relationship between DTI values and disease duration time and thyroid peroxidase antibodies (TPOAb) levels.

METHODS

We prospectively included 36 patients with HT (mean age 41.6 ± 13.8 years, range 18-64 years) and 18 age and sex-matched healthy control subjects (mean age 41.6 ± 13.1 years, range 18-63 years). All patients were euthyroid at the time of imaging. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) values of 15 distinct neuroanatomical locations were measured and compared.

RESULTS

FA values of the patients with HT were lower in cingulum, globus pallidus (GP), cerebellar white matter (CWM) than the control (P = .019, .002, and <.001, respectively). MD values of the CWM in patients were higher than the control (P = .008). AD values of patients with HT were lower in the cingulum, posterior limbs of the internal capsule, GP, and putamen (P = .038, .038, .030, and .045, respectively). RD values of cingulum and CWM in HT were higher than controls (P <.001 and P = .011, respectively). There was a negative relationship between the FA values of PLIC and a positive relationship between the MD values of the corona radiata and TPOAb levels were detected.

CONCLUSIONS

The current DTI study presented microstructural changes in the neurocognitive-related areas that may be related to accompanying neurological findings in HT.

Hashimoto's Encephalopathy and Seizure Disorders

Hashimoto's encephalopathy (HE) is a rare, clinically heterogeneous condition associated with positive thyroid autoantibodies. It is increasingly recognized as an important and treatable cause of autoimmune encephalopathy. Thyroid-associated antibodies such as thyroperoxidase (TPO) antibody, thyroglobulin (TG) antibody, and thyrotropin receptor (TR) antibody were found in HE patients with seizure disorders. Although antithyroid antibodies are required for the diagnosis of HE, their role in the pathogenesis of HE remains uncertain. Instead of playing a key role in the pathophysiology processes of HE, it is suggested that thyroid-associated antibodies are hallmarks of HE. Seizure disorders were found in approximately two-thirds of HE patients, and common anticonvulsant therapy alone is usually ineffective. Some patients did not respond to any antiepileptic drugs. The use of immunotherapy can effectively control seizure disorders. Electroencephalography and imaging findings are not specific to HE patients and can also be seen in other causes of encephalopathies. However, the prognosis in the majority of patients with HE was usually good if it is diagnosed and treated correctly.

Hashimoto Encephalopathy

Hashimoto encephalopathy (HE) is a steroid-responsive, acute or subacute encephalopathy, characterised by autoimmune thyroiditis associated with elevated antithyroid antibody titres. An 11-year-old girl was admitted to the Department of Paediatrics with generalised tonic-clonic seizures, left facial paralysis and right hemiparesis. Ceftriaxone and acyclovir were applied, and methyl prednisolone 2 mg kg^-1 day^-1 was administered orally. The hemiparesis improved on the 3^rd day of treatment, but the facial paralysis persisted into the 15^th day. When she developed somnolence, she was transferred to the paediatric intensive care unit and provided with respiratory support after intubation. Antithyroid peroxidase (Anti-TPO) and Antithyroglobulin antibody (Anti-Tg) levels were measured at 112.3 IU mL^-1 and 74.6 IU mL^-1, respectively. HE was considered as the provisional diagnosis, for which intravenous methyl prednisolone 30 mg kg^-1 for 5 days followed by prednisolone 1.5 mg kg^-1 day^-1 were administered. The patient's clinical status did not improve; therefore, she underwent therapeutic plasma exchange (1/1 ratio) for 8 days, followed by intravenous immunoglobulin 1 gr kg^-1 for 2 days. As her clinical condition did not improve, rituximab and endoxane treatments were planned. Unfortunately, these treatments were postponed as she developed ventilator-associated pneumonia at the follow-up. She developed septic shock on the 14th day of follow-up, and noradrenaline and dopamine infusions were commenced. Despite all the efforts, she remained unresponsive and died from cardiac arrest. By reporting this case, we aimed to stress that HE should be considered as an aetiology of encephalopathy when infectious, neoplastic, autoimmune, toxic and metabolic causes are excluded.

[A case of Hashimoto's encephalopathy successfully treated with cyclophosphamide pulse therapy]

Hashimoto's encephalopathy has been described as an autoimmune disorder which demonstrates favorable response to corticosteroid therapy. However, steroid-resistant cases which require additional treatment are frequently reported, and there is no consensus how such cases should be treated. We present a 69 years-old man, who progressed cognitive dysfunction in the past three months. Anti-thyroid and anti-NH₂ terminal of alpha-enolase antibodies were positive. Because initial corticosteroid therapy was ineffective, cyclophosphamide (CPA) pulse therapy was added, and his cognitive function was immediately improved. He had no relapse after tapering dose of corticosteroid for three years. CPA pulse therapy should be considered for steroid-resistant Hashimoto's encephalopathy.

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.

An Unusual Cause of Frequent, Sudden, Transient, Unexplained Falls and New-Onset Status Epilepticus: Case Report and Mini-Review

We report a 14-year old adolescent Caucasian female, who presented with frequent, sudden, transient, and unexplained falls leading to multiple serious injuries to her head and extremities requiring several visits to the emergency department. She was evaluated numerous times and imaging studies, echocardiogram, electrocardiogram, and electroencephalogram studies were all normal. She eventually presented to outside emergency department with dystonic posturing and status epilepticus and was transferred to our pediatric intensive care unit for further management. She was diagnosed with an uncommon, underrecognized and underdiagnosed condition. To our knowledge there is no such previous report in a pediatric patient.

Focal neurological presentation in Hashimoto's encephalopathy mimicking a vascular occlusion of the middle cerebral artery

Hashimoto's encephalopathy is a rare form of autoimmune encephalopathy. It is likely an underdiagnosed entity especially in the setting of focal neurological defects. We report a case of a 49-year-old man who presented with "strange behavior"of a day's duration. Examination was significant only for lethargy, poor attention span and agitation. Routine labs revealed leucocytosis. Head CT scan was unremarkable. Lumbar puncture showed high white blood cells with lymphocytosis and elevated protein level. The patient was empirically treated for meningitis without improvement. His symptoms progressed to sudden right-sided weakness, ataxia and right facial droop. The MRI and magnetic resonance angiogram (MRA)were normal. The patient’s focal neurological signs improved spontaneously. Encephalopathy work-up was negative except for positive anti-Thyroid Peroxidaseand antithyroglobulin. The patient was treated as Hashimoto encephalopathy with steroids and azathioprine with marked improvement. Our case highlights how focal neurological findings can potentially mislead the provider to consider vascular aetiologies in Hashimoto's encephalopathy.

Hashimoto encephalopathy: literature review

Hashimoto encephalopathy (HE) presents as an encephalopathy without central nervous system infection or tumor. HE is associated with autoimmune thyroiditis and is thus considered to be an autoimmune disorder. The prevalence of HE is low, but death and status epilepticus have been reported. HE manifests with a wide range of symptoms that include behavioral changes and confusion. Elevated thyroid antibodies are present in the majority of cases and are required for the diagnosis of HE. Normal brain MRI findings are found in the majority of patients diagnosed with HE. The most consistent CSF abnormality noted in HE patients is the presence of elevated protein. Most HE patients respond well to steroid therapy. Clinical improvements are also observed with IV immunoglobulin and plasmapheresis. In conclusion, it is now generally accepted that the diagnosis of HE must include encephalopathy characterized by cognitive impairment associated with psychiatric features, such as hallucinations, delusions, and paranoia. Autoimmune encephalitis and prion disease should be considered in the differential diagnosis due to the similarity of the clinical features of these conditions to those of HE.

Delirium in Parkinson's Disease: A Cocktail Diagnosis

Mental disturbances have been described in patients with Parkinson's Disease (PD). Of these, the common conditions are delirium and psychosis. Delirium has been attributed to change of environment, especially hospital stay and infections; while psychosis is due to drugs like dopamine agonists. This is a case of a 75-year-old male, on levodopa therapy for PD, who presented with delirium and ended up with a cocktail diagnosis: Cryptococcal meningitis, Hashimoto's Encephalopathy (HE), Urinary tract infection with acute renal failure, Uremic encephalopathy and Levodopa induced psychosis. This case report, therefore, highlights the need to look for other causes of delirium in a patient with PD who is on levodopa therapy.

Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT): case report of reversible coma and status epilepticus in an adolescent patient and review of the literature

Steroid-responsive encephalopathy associated with autoimmune thyroiditis (SREAT), also termed Hashimoto's encephalopathy (HE), is a rare immune-mediated disorder and is also affecting children and adolescents. It is characterized by altered mental status, seizures, and cognitive dysfunction. Therapeutic options include steroid treatment and prognosis range from complete recovery, a relapsing course to long-term cognitive sequelae. We describe a previously healthy 13-year-old girl presenting to the emergency room with coma and refractory status epilepticus. Generalized tonic-clonic seizures persisted after pre-hospital infusion of antiepileptic medication. She was found to have highly elevated levels of thyroid-stimulating hormone and anti-thyroid peroxidase antibodies not only in blood but also in cerebrospinal fluid while showing negative results for traumatic, infectious, metabolic, toxic, neoplastic, or other known specific autoimmune diseases. Cranial neuroimaging revealed no abnormality. A diagnosis of SREAT was established, and the patient improved rapidly on corticosteroids and levothyroxine therapy. However, 3 months after the discontinuation of steroid treatment, the girl relapsed. The current literature regarding SREAT is reviewed and summarized.

CONCLUSION

In children with SREAT, early diagnosis and treatment with corticosteroids is crucial and can lead to rapid clinical improvement. Clinicians should be aware of this uncommon but treatable condition, especially in female adolescents with unexplained seizures or an encephalopathic state.

Reversible splenial lesion in auto-immune thyroid disease: a case report

Reversible lesions of the splenium of the corpus callosum constitute a clinicoradiological syndrome that has been associated to various medical conditions. We report the case of a 47-year-old man who presented with encephalopathy associated to auto-immune thyroid disease in which a reversible splenial lesion was isolated. Although encephalopathy associated to auto-immune thyroid disease is characterized by variable radiological findings, it has only been once associated with a reversible splenial lesion.

Recurrent status epilepticus associated with Hashimoto's encephalopathy

Hashimoto's encephalopathy (HE) is an infrequent disease with no well-known physiopathology. Status epilepticus is rarely reported in association with HE. We describe the 7-year evolution of a young woman who presented with recurrent status epilepticus as the main complication of HE. This evolution was especially marked by the occurrence of steroid-refractory symptoms and a poor outcome with persistent cognitive and behavioral consequences. We point out that the frontal lobes are especially implicated in these symptoms. This patient highlights the risk of multiple relapses and the need for a long follow-up period. We describe her clinical and paraclinical features, compare this patient to similar case reports, and comment on her outcome.

Hashimoto encephalopathy: a rare intricate syndrome

Recently, several patients have been reported with various signs of encephalopathy and high thyroid antibody levels together with good responsiveness to glucocorticoid therapy. Despite the various clinical presentations, these cases have been termed "Hashimoto encephalopathy" (HE). Although all of the pathogenic components have not yet been clearly elucidated, it is believed that brain vasculitis and autoimmunity directed against common brain-thyroid antigens represent the most likely etiologic pathway. The most common clinical signs include unexplained or epilepsy-like seizures resistant to anti-convulsive treatment, confusion, headaches, hallucinations, stroke-like episodes, coma, impairment of cognitive function, behavioral and mood disturbance, focal neurological deficits, disturbance of consciousness, ataxia, and presenile dementia, together with the presence of high thyroid antibody levels, especially against thyroperoxidase (TPOab). In most cases, the thyroid function is normal or decreased; the thyroid function is rarely increased. The examination of the cerebrospinal fluid, EEG, MRI, SPECT, and neuropsychological examinations are primarily used as diagnostic tools. Most cases showed neural symptoms for months before the acute onset; in some cases, a dramatic acute onset was described. Once the diagnosis is made, corticosteroid treatment usually provides a dramatic recovery. The authors also present a short review of literary cases reported in last decade.

Immune mediated diseases and immune modulation in the neurocritical care unit

This chapter will review the spectrum of immune-mediated diseases that affect the nervous system and may result in an admission to the neurological intensive care unit. Immunomodulatory strategies to treat acute exacerbations of neurological diseases caused by aberrant immune responses are discussed, but strategies for long-term immunosuppression are not presented. The recommendations for therapeutic intervention are based on a synthesis of the literature, and include recommendations by the Cochrane Collaborative, the American Academy of Neurology, and other key organizations. References from recent publications are provided for the disorders and therapies in which randomized clinical trials and large evidenced-based reviews do not exist. The chapter concludes with a brief review of the mechanisms of action, dosing, and side effects of commonly used immunosuppressive strategies in the neurocritical care unit.

Autoimmune encephalopathy associated with thyroid autoantibodies as the cause of reversible cognitive impairment

We herewith describe a patient with acute confusion, expressive aphasia and generalized seizures. A through workup excluded most causes of encephalopathy. He was, however, found to have TSH=18.6 MIU/ml, T3reverse=0.44nmol/L, T4=0.8ng/dl and Anti-Thyroid-Peroxidase AB titer >1000 IU/ml. Based on the above findings the patient was diagnosed with Hashimoto's encephalopathy and his mental status showed dramatic improvement (MMS 30/30) with high dose prednisone.

Hashimoto's encephalopathy is rare disorder of presumed autoimmune origin characterized by cognitive decline, seizures, neuro-psychiatric symptoms, high titers of Anti-Thyroid-Peroxidase AB, and a positive response to steroids.