A Case of Lithium-Induced Polyendocrinopathy Including Thyroid Storm

Chronic lithium therapy can adversely affect thyroid, parathyroid, and kidney function. We present a 67-year-old man on chronic lithium therapy for bipolar disorder who developed thyroid storm, hypercalcemia, and nephrogenic diabetes insipidus following lithium intoxication. Diagnostic studies revealed no infectious precipitant of thyroid storm, with negative thyroid stimulating immunoglobulin and antithyroid peroxidase antibody levels. Thyroid ultrasound demonstrated small thyroid glands with decreased blood flow, not suggestive of Graves' disease. The patient's symptoms improved on only a few weeks of antithyroid drug and was discharged home without thyroid medications. His thyroid function followed a thyroiditis pattern when it dipped into the hypothyroid range before returning to normal without further interventions. To our knowledge, this is the first reported case of lithium-induced thyroiditis precipitating a thyroid storm and the third reported occurrence of thyroid storm in the context of thyroiditis. The patient's hospital course was further complicated by the development of hypercalcemia and nephrogenic diabetes insipidus requiring specialized treatments. We review the literature on mechanisms and treatment of lithium-induced thyroid dysfunction, hypercalcemia, and diabetes insipidus. Lithium-treated patients should have periodic thyroid function tests, and electrolyte measurements, especially following lithium dose adjustment.