Diabetes insipidus as a presenting manifestation of Rathke's cleft cyst

Rathke's cleft cysts (RCC) are cystic sellar and suprasellar lesions derived from remnants of Rathke's pouch, lined by cuboidal or columnar epithelium. RCC are usually asymptomatic but can present with headache, visual impairment, panhypopituitarism and hypothalamic dysfunction. Diabetes Insipidus as a presenting symptom of RCC is reported, but rare. We present a case of a 48-year-old male presenting with polyuria and on investigations found to have central diabetes insipidus due to a sellar RCC. Patient underwent transsphenoidal surgery with complete excision with resolution of his symptoms. His polyuria resolved post-surgery without vasopressin replacement, which has never been reported.