Pituitary apoplexy precipitating diabetes insipidus.

Objective: To describe a case of pituitary apoplexy complicated by diabetes insipidus and to review management of patients with pituitary apoplexy and water excretion disturbances associated with transsphenoidal surgery.

Methods: We describe clinical, laboratory, and radiologic findings in a patient with pituitary apoplexy and central diabetes insipidus.

Results: A 74-year-old woman presented with severe headache and sudden loss of vision for 12 hours, accompanied by thirst and frequent urination. Visual field examination demonstrated bitemporal hemianopsia. Her laboratory findings were significant for a serum sodium level of 152 mEq/L and urine specific gravity of <1.005. A magnetic resonance imaging scan of her pituitary gland identified a 3.5-cm suprasellar mass compressing the optic chiasm. She subsequently underwent transsphenoidal pituitary surgery with subtotal resection of this mass. Microscopic evaluation of tumor tissue revealed a pituitary adenoma with evidence of recent infarct and hemorrhage. Her clinical and biochemical course was consistent with the triphasic response that may occur after pituitary surgery related to damage to the hypothalamus and supraopticohypophyseal tract.

Conclusion: Pituitary apoplexy may be rarely associated with diabetes insipidus.