An 18-month-old, spayed female, miniature Poodle dog was presented for preoperative evaluation of severe azotemia prior to surgical correction of bilateral medial patellar luxation. On physical examination, the dog appeared emaciated and less than 5% dehydrated. Results of hematological analyses indicated leukopenia, azotemia, and hypercalcemia. Additionally, urinalysis revealed proteinuria and low specific gravity compatible with chronic kidney disease (CKD). Ultrasonography showed bilaterally small irregular kidneys. To make a definitive diagnosis, renal biopsy was performed under the guidance of ultrasound. Histopathology revealed a high percentage of fetal glomeruli, which was consistent with congenital renal dysplasia. This case describes clinical and histopathological features of congenital renal dysplasia diagnosed by percutaneous renal biopsy.

Key words: Dog, Renal biopsy, Renal dysplasia