Case report of Hashimoto encephalopathy in a 21-year-old female patient

Hashimoto encephalopathy is a rarely diagnosed autoimmune neurological disorder, associated with the presence of antithyroid antibodies. The variability of clinical presentation, rarity of the disease, and absence of specific diagnostic markers make timely diagnosis very complicated. This article describes a clinical case of a female patient with Hashimoto encephalopathy and discusses diagnosis, differential diagnosis and treatment approaches. We emphasize the importance of establishing a timely diagnosis, considering high efficacy of targeted treatment.

Episodic Hemiparesis, Cognitive Decline, and Seizures in a Woman With Pernicious Anemia

A 46-year-old woman with a history of pernicious anemia, sought care for intermittent episodes of weakness in her right upper extremity and speech difficulties followed by a headache. It was initially thought that she had migraine headaches. Blood tests showed increased thyrotropin and low free thyroxine levels, and she was diagnosed with Hashimoto thyroiditis. She initiated treatment with levothyroxine. One month later, the patient had a confusional episode and over the course of the following 2 months, the cognitive difficulties progressed. She was brought to the emergency department after a generalized tonic-clonic seizure. On examination, she was profoundly encephalopathic. Formal bedside cognitive testing could not be obtained. Findings of magnetic resonance imaging of the brain were normal. Electroencephalography revealed diffuse slowing. Cerebrospinal fluid analysis showed increased protein concentration and lymphocytic pleocytosis. Thyroid peroxidase antibody value was markedly increased. Thyroglobulin antibody value was also increased. Consistent with her history of pernicious anemia, she was positive for gastric parietal cell antibodies. The clinical presentation was compatible with steroid-responsive encephalopathy associated with autoimmune thyroiditis, also known as Hashimoto encephalopathy. The patient started levetiracetam therapy and had no further seizures. She received intravenous methylprednisolone. At the completion of treatment, her confusion rapidly and substantially improved. She was discharged home on oral prednisone. She also started pantoprazole, calcium, and vitamin D supplementation and Pneumocystis jirovecii prophylaxis. For long-term immunotherapy, she initiated methotrexate. Three months later, the patient and her family reported 90% improvement in her cognitive functioning and resolution of the episodes of hemiparesis. The patient continued tapering prednisone. It was recommended that she continue methotrexate for 5 years before discontinuing. Steroid-responsive encephalopathy associated with autoimmune thyroiditis, also known as Hashimoto encephalopathy, was initially described as strokelike episodes and subacute encephalopathy months after the onset of autoimmune (Hashimoto) thyroiditis.

Brain dysfunction and thyroid antibodies: autoimmune diagnosis and misdiagnosis

Hashimoto encephalopathy, also known as steroid-responsive encephalopathy associated with autoimmune thyroiditis, has been defined by subacute onset encephalopathy, with elevated thyroid antibodies, and immunotherapy responsiveness, in the absence of specific neural autoantibodies. We aimed to retrospectively review cases referred with suspected Hashimoto encephalopathy over a 13 year period, and to determine the clinical utility of thyroid antibodies in the course of evaluation of those patients. One hundred and forty-four patients (all thyroid antibody positive) were included; 72% were women. Median age of symptom onset was 44.5 years (range, 10-87). After Mayo Clinic evaluation, 39 patients (27%) were diagnosed with an autoimmune CNS disorder (autoimmune encephalopathy [36], dementia [2] or epilepsy [1]). Three of those 39 patients had neural-IgGs detected (high glutamic acid decarboxylase-65, AMPA-receptor and neural-restricted unclassified antibody), and 36 were seronegative. Diagnoses among the remaining 105 patients (73%) were functional neurological disorder (n = 20), neurodegenerative disorder (n = 18), subjective cognitive complaints (n = 14), chronic pain syndrome (n = 12), primary psychiatric (n = 11), sleep disorder (n = 10), genetic/developmental (n = 8), non-autoimmune seizure disorders (n = 2), and other (n = 10). More patients with autoimmune CNS disorders presented with subacute symptom onset (p < 0.001), seizures (p = 0.008), stroke-like episodes (p = 0.007), aphasia (p = 0.04) and ataxia (p = 0.02), and had a prior autoimmune history (p = 0.04). Abnormal brain MRI (p = 0.003), abnormal EEG (p = 0.007), CSF inflammatory findings (p = 0.002) were also more frequent in the autoimmune CNS patients. Patients with an alternative diagnosis had more depressive symptoms (p = 0.008), anxiety (p = 0.003), and chronic pain (p = 0.002). Thyoperoxidase antibody titer was not different between the groups (median 312.7 vs 259.4 IU/mL, p = 0.44, normal range <9 IU/mL). None of the non-autoimmune group and all but three of the CNS autoimmune group (two with insidious dementia presentation, one with seizures only) fulfilled the autoimmune encephalopathy criteria proposed by Graus et al (sensitivity 92%, specificity 100%). Among patients who received an immunotherapy trial at our institution and had objective post-treatment evaluations, the 16 responders with autoimmune CNS disorders more frequently had inflammatory CSF, compared to 12 non-responders, all eventually given an alternative diagnosis (p = 0.02). Seventy-three percent of patients referred with suspected Hashimoto encephalopathy had an alternative non-immune mediated diagnosis, and more than half had no evidence of a primary neurological disorder. Thyroid antibody prevalence is high in the general population, and does not support a diagnosis of autoimmune encephalopathy in the absence of objective neurological and CNS-specific immunological abnormalities. Thyroid antibody testing is of little value in the contemporary evaluation and diagnosis of autoimmune encephalopathies.

The diagnostic challenge of Hashimoto’s Encephalopathy

Introduction: The diagnosis of Hashimoto Encephalopathy (HE) is generally considered in patients with a wide range of neurological symptoms, accompanied by normal or nonspecific findings on magnetic resonance imaging and CSF, normal thyroid function or mild hypothyroidism, increased serum levels of thyroid peroxidase antibodies, and clinical response to steroids. Case report: We attended a 76-year-old patient, brought by lowering the level of consciousness 3 days ago, insidiously. Neurological exam: did not obey commands, and only said incomprehensible sounds. Myoclonus in upper limbs and random multidirectional movements of the eyes with horizontal nystagmus, rapid phase to the left. Cranial tomography had only signs of microangiopathy. Electroencephalogram: diffuse slow waves, with no signs of status epilepticus. Laboratory tests: there were increased protein in CSF (107mg/dl) and Anti-TPO serum (>1000 U/ml) levels, without other specific alterations. After these results, therapy with Methylprednisolone 1g/day for 5 days, and Levothyroxine, were chosen. There was a gradual improvement in the neurological condition from the 3rd day of treatment. Conclusion: immediate recognition of Hashimoto encephalopathy is important. Although the pathogenesis is unknown, the disorder is treatable. This entity should always be remembered for the proper direction of therapeutic approaches, thus enabling better outcomes to the patient.

Hashimoto encephalopathy with positive oligoclonal bands in cerebrospinal fluid

Introduction: Hashimoto encephalopathy (HE) is a rare and often misdiagnosed entity. Except high levels of the thyroid peroxidase (anti-TPO) and antithyroglobulin (anti-TG) antibodies, neurophysiological and psychological tests are beneficial for the diagnosis. The presence of oligoclonal bands in the cerebrospinal fluid (CSF) of these patients is very rare. We present a patient with HE and oligoclonal bands in CSF with good clinical response on corticosteroid therapy. Case report: Male patient, 39 years old, suddenly developed focal neurologic deficit. He had elevated anti-TPO and anti TG antibodies, impaired concentration on psychologist report and oligoclonal bands in CSF. Slowing of electroencephalography activity was normalized with full clinical recovery of the patients, after corticosteroid therapy. The patient is in clinical remission 5 years after establishing the diagnosis. Conclusion: Oligoclonal bands in the CSF may be helpful in the diagnosis of HE considering that it is still poorly understood entity. Also fast diagnosis of HE and treatment with corticosteroids are important for a full recovery of this patients.