Hashimoto's encephalopathy: a rare case report of Hashimoto's thyroiditis with seizure.

Introduction and importance: Hashimoto's thyroiditis (HT) is a common autoimmune condition that causes hypothyroidism. It is characterized by a wide range of symptoms, from conventional ones to rare and severe neurological manifestations. Seizures are a very uncommon symptom of HT, requiring a deep understanding and careful management owing to the challenges involved in diagnosing and the severe implications. Case presentation: A 19-year-old female with a medical history of untreated hypothyroidism caused by HT presented with a seizure characterized by generalized tonic-clonic movements. She displayed symptoms of fatigue, confusion, and swelling in the extremities. The laboratory results indicated a significant case of autoimmune hypothyroidism. The results of the brain imaging and EEG tests were within the expected range and did not show any abnormalities. The treatment regimen consisted of levothyroxine, levetiracetam, and methyl-prednisolone, which led to the cessation of seizures and the patient's recovery from the postictal state. Clinical discussion: While managing HT itself is well-defined, tackling the neurologic complexities of Hashimoto's encephalopathy (HE) takes a multifaceted approach. Conclusion: This case highlights the intricate nature of diagnosing and managing neurological symptoms caused by HT, namely seizures. Patients presenting with unexplained seizures and autoimmune thyroid illness should be mindful of the possibility of HE, an uncommon condition. Management includes the attainment of normal thyroid function and the consideration of immunosuppressive therapy for severe instances of HE.