Successful treatment of severe iatrogenic hypercalcemia and acute kidney injury with hemodialysis in a cat.

A 4-year-old male castrated domestic shorthair cat was diagnosed with a urethral obstruction after presenting for vomiting, inappetence, and inappropriate urination. The cat developed iatrogenic hypercalcemia (ionized calcium > 4 mmol/L, total calcium 57 mg/dL) and an acute kidney injury (creatinine 9.81 mg/dL) suspected to be a consequence of an overdose of calcium gluconate. Approximately 12 h after admission, the cat became comatose and developed cardiovascular instability. A 6-h hemodialysis treatment was performed using continuous venovenous hemodiafiltration on the Prismaflex platform and hypercalcemia resolved during treatment. The cat's creatinine normalized (1.01 mg/dL) within 72 h and the cat was discharged after 6 days of hospitalization. The cat subsequently developed signs of upper respiratory and gastrointestinal disease. Diagnostics including upper gastrointestinal endoscopy and bronchoscopy showed evidence of diffuse calcification of the trachea and gastric mucosa. This case demonstrates the successful application of hemodialysis in veterinary medicine to treat an acute kidney injury and iatrogenic hypercalcemia and provides unique documentation of its potential long-term sequelae.