Abstract
History A 13-year-old 9.4-kg spayed female Whippet presented to a university teaching hospital for evaluation of neurologic signs including ataxia, a wide-based stance, shaking, and an episode of falling over. For the 2 weeks prior, the dog had been receiving oral meloxi-cam (dose unknown) prescribed by another veterinarian for suspected osteoarthritis. The dog's appetite was reduced, the dog had 2 bilious vomits the day prior to presentation, and the owners estimated 1 kg of recent weight loss. A heart murmur had first been noted 11 months prior but had not been investigated. On presentation, the dog was quiet but alert and responsive. A full neurologic examination was not reported. Tachycardia (heart rate, 220 beats/ min; reference interval, 70 to 120 beats/min) and a grade 3 to 4/6 left apical systolic murmur were noted. Perfusion parameters were otherwise normal (pink mucous membranes, capillary refill time of 1.5 seconds, strong pulses, warm extremities). Severe cranial abdominal pain was evident on palpation. The dog exhibited marked systemic hypertension, with an oscillometric systolic/diastolic blood pressure of 280/196 mm Hg and a mean arterial pressure of 237 mm Hg (reference interval, 95–110 mm Hg). Systemic hypertension persisted despite administration of analgesia (detailed in the Treatment and Outcome section herein), with mean arterial pressure consistently 162 to 228 mm Hg. Initial screening diagnostics included a CBC, serum biochemistry profile, and urinalysis. The only hematologic abnormality was a moderate lympho-penia (0.57 × 10 9 cells/L; reference interval, 1.05 × Ataxia, vomiting, and inappetence in a 13-year-old spayed female Whippet 10 9 to 5.1 × 10 9 cells/L) consistent with a stress response. Biochemistry revealed a moderate azotemia (creatinine, 310 µmol/L; reference interval, 44 to 159 µmol/L; and urea, 19.2 mmol/L; reference interval, 2.5 to 9.6 mmol/L). Urine specific gravity of 1.012 was supportive of kidney disease. Urinalysis and wet microscopy revealed a 3+ proteinuria and hematuria on dipstick and pyuria (9 cells/µL), hematuria (27 cells/µL), and epithelial celluria (5 cells/µL) on sediment examination. Aerobic culture was negative. Four-view thoracic radiography was performed. Left lateral and ventrodorsal (VD) radiographs are shown (Figure 1). Formulate differential diagnoses, then continue reading.