ERRATUMThis case report was originally published in the AVJ in December 2005 ( Aust Vet J 2005;83:732 -735), but the units for deamino-8-D-arginine vasopressin (DDAVP) were incorrectly given in milligrams instead of micrograms. The paper is reprinted here in full with the correct units for DDAVP. Here a case of trauma-induced central DI in a cat and successful long-term treatment with parenteral DDAVP is described. Trauma-induced central diabetes insipidus in a cat Case reportA 1-year-old neutered male domestic shorthair cat was referred with a 4 week history of polydipsia that began immediately following a fall from an 8 m balcony. Veterinary attention was not sought at the time of the accident because, although mentation was depressed for several minutes, the cat's desire and capacity to consume water over the following hours was perceived by the owner to preclude any serious injury.Daily water intake measured by the owner for 13 consecutive days prior to presentation ranged between 900 and 1500 mL (average 1135 mL/day). Appetite was unchanged and the diet consisted predominantly of commercial tinned food supplemented with a commercial dry food and raw kangaroo meat.Upon presentation, the cat was bright and in good body condition (body condition score 6 out of 9; 9 body weight 6.2 kg). Physical examination, including complete neurological examination, was unremarkable. Urine collected by manual expression of the urinary bladder revealed no chemical abnormalities (Mulitsticks, Bayer) and USG determined by hand-held refractometer was 1.008. Haematological analysis was unremarkable. Biochemical parameters, including electrolytes, were within the reference ranges for normal cats with the exception of mild elevations in albumin (42 g/dL; reference range 27 to 38 g/dL) and alkaline phosphatase (57 IU/L; reference range < 51 IU/L). The following day a complete abdominal ultrasound examination was performed and was unremarkable. Urine was collected by antepubic cystocentesis and repeat urinalysis and urine culture was performed (Medicine and Microbiology Laboratory, University of Queensland). The urine was hyposthenuric (urine specific gravity [USG] 1.004) but otherwise unremarkable.Diabetes insipidus was suspected and a modified water deprivation test was performed (Figure 1).

A 1-year-old neutered male domestic shorthair cat presented with a 4-week history of polydipsia that began immediately after an 8 metre fall. Trauma-induced central diabetes insipidus was suspected on the basis of the identification of hyposthenuria, normal haematology and serum biochemistry profile and unremarkable abdominal ultrasound examination. Failure to concentrate urine with water deprivation followed by production of hypersthenuric urine with administration of the synthetic antidiuretic hormone, Deamino-8-D-arginine vasopressin (DDAVP), confirmed the diagnosis of central diabetes insipidus. Treatment via conjunctival administration of DDAVP failed to attenuate the polydipsia, however, resolution of polydipsia was achieved with subcutaneous administration of DDAVP and the cat remains eudipsic with twice daily subcutaneous DDAVP administration 17 months after diagnosis.