Presumptive diagnosis of central diabetes insipidus with possible origin secondary idiopathic etiology

Abstract

Diabetes insipidus (DI) is an infrequent endocrine disorder in cats caused by alteration in the synthesis and/or secretion of antidiuretic hormone (ADH), or by renal tubular inability to respond to the hormone. This endocrine disorder can have varied origins. The aim of this article was to report a case of diabetes insipidus in a 5-year-old mixed breed female cat, complaining of polyuria (PU) and polydipsia (PD), initially diagnosed as chronic kidney disease (CKD). The patient had already been evaluated by a professional, who found anemia, dehydration, azotemia and ultrasound changes suggestive of acute renal failure. Due to the concern of the owner, the patient was evaluated for another professional that observed a history, previous laboratory tests, and it was observed that the animal had a satisfactory body score, normal colored and hydrated mucous membranes, presence of gingivitis in the molar and premolar teeth, and moderate halitosis. The urinalysis showed isosthenuria, with no other alterations in the urinary analytes. Ultrasound examinations revealed maintenance of the corticomedullary architecture, discreet points of cortical mineralization and discreet dilation of the renal pelvis. The differentials of diabetes mellitus and hyperthyroidism were ruled out. Based on the clinical condition, diabetes insipidus was suspected, and the diagnosis was confirmed after a positive response to the use of desmopressin by the conjunctival route and increased urinary density.