A case of central diabetes insipidus associated with a congenital cyst of the sella turcica in a young cat.

Central diabetes insipidus (CDI) is a rare cause of polyuria and polydipsia in cats, resulting from inadequate or impaired secretion of antidiuretic hormone from the posterior pituitary gland. Recognised causes include head trauma, central nervous system (CNS) neoplasia, idiopathic CDI and congenital pituitary cysts. Apart from one cat with CNS lymphoma, the few previously reported feline cases have described CDI in young cats with a previous history of trauma, but brain imaging has rarely been performed to look for underlying anatomical abnormalities. This report describes the first case of CDI in a cat with a confirmed congenital pituitary cyst and, as in previous cases, demonstrates successful treatment with desmopressin.