The syndrome of inappropriate secretion of antidiuretic hormone: an unusual presentation for childhood craniopharyngioma: report of three cases.

Objective And Importance: Childhood craniopharyngiomas may present with variable endocrine dysfunctions. However, hyponatremia secondary to the syndrome of inappropriate secretion of antidiuretic hormone has never been reported. We describe three children with craniopharyngioma who presented with hyponatremia.

Clinical Presentation: Three children had hyponatremia at presentation, two of whom had experienced generalized seizures. Urine sodium levels measured in two patients were abnormally high. Neuroimaging tests, including computed tomography and magnetic resonance imaging, showed a large partially calcified and partially cystic craniopharyngioma in the sellar/suprasellar location.

Intervention: Intake of fluids was restricted for each patient, with improvement of hyponatremia, and each patient subsequently underwent a successful tumor resection. Postoperatively, all patients developed panhypopituitarism, including diabetes insipidus, and needed multiple hormonal replacement therapy.

Conclusion: Endocrine dysfunctions at diagnosis are commonly associated with childhood craniopharyngiomas, but the association of the syndrome of inappropriate secretion of antidiuretic hormone with craniopharyngioma has never been reported. Craniopharyngiomas should be included as a possibility in making the differential diagnosis of the syndrome of inappropriate secretion of antidiuretic hormone in children.