CENTRAL DIABETES-INSIPIDUS IN DOGS - 20 CASES (1986-1995)

Objective-To assess clinical signs, biochemical findings, results of m odified water deprivation and other diagnostic tests, response to trea tment, and survival time in dogs with central diabetes insipidus (CDI) . Design-Retrospective study. Animals-20 dogs with CDI. Procedure-Sign alment, history, physical examination, results of diagnostic tests, re sponse to treatment, and survival time were extracted from the medical record of each dog and supplemented with information obtained from ow ners via telephone. Results-isosthenuria or hyposthenuria was a consis tent finding. Seven dogs with complete CDI and 13 dogs with partial CD I were identified on the basis of results of a modified water deprivat ion test. Dogs treated with desmopressin acetate responded well to tre atment. Seven dogs were alive 18 to 72 months (median, 36 months) afte r diagnosis, and 10 dogs died or were euthanatized 1 week to 2 years ( median, 2 months) after diagnosis. Seven of 10 dogs that died develope d neurologic signs after diagnosis of CDI. Computed tomography reveale d a mass in the region of the pituitary gland in 5 of 7 dogs. Necropsy of 6 dogs, including 2 dogs on which computed tomography had been per formed, revealed neoplasia in the pituitary gland. Clinical Implicatio ns-Onset of neurologic signs after diagnosis of CDI in middle- to old- aged dogs indicates that CDI may not be a benign disease that is treat ed easily. Brain imaging is recommended after diagnosis of CDI in midd le- to old-aged dogs. Also, because many dogs are isosthenuric on init ial examination, CDI cannot be ruled out as a cause of polyuria and po lydipsia on the basis of lack of hyposthenuria.