A pediatric client with diabetes insipidus (DI) is being treated with vasopressin. The nurse would assess the client closely for signs and symptoms of which condition?

A. Thyroid storm is related to hyperthyroidism and is not directly associated with vasopressin treatment. B. Vitamin D toxicity is unrelated to vasopressin and is not a concern in this scenario. C. Cushing syndrome is caused by excess cortisol and is not related to vasopressin therapy. D. SIADH is characterized by excessive release of antidiuretic hormone, which can lead to water retention and hyponatremia. Since vasopressin is an antidiuretic hormone analog, it can cause similar effects if not carefully monitored.