Lithium-induced Hashimoto's encephalopathy: a case report

Area of Science:

• Neurology
• Endocrinology
• Psychiatry

Background:

• Hashimoto's encephalopathy is a rare neurological disorder associated with autoimmune thyroid disease.
• Lithium is a common mood stabilizer for bipolar disorder, but can have various side effects.
• This case highlights a potential link between lithium use and the development of Hashimoto's encephalopathy.

Observation:

• A 61-year-old woman with bipolar disorder developed encephalopathy after lithium treatment.
• The patient had a history of lithium-induced thyrotoxicosis and was on levothyroxine for hypothyroidism.
• Elevated antithyroid antibodies were found in serum and cerebrospinal fluid.

Findings:

• Lithium therapy precipitated Hashimoto's encephalopathy in a patient with pre-existing thyroid autoimmunity.
• Cerebrospinal fluid analysis revealed elevated protein and the presence of antithyroid antibodies.
• Encephalopathy symptoms resolved rapidly following intravenous methylprednisolone pulse therapy.

Implications:

• Lithium may induce autoimmune responses targeting shared antigens in the thyroid and brain.
• This case underscores the importance of monitoring for neurological complications in patients on lithium, especially those with thyroid conditions.
• Early recognition and treatment with corticosteroids are crucial for managing lithium-induced Hashimoto's encephalopathy.