Ultrasound-guided percutaneous drainage for treatment of pyonephrosis in two dogs.

Pyonephrosis refers to suppurative destruction of the parenchyma of the kidney with complete or nearly complete loss of renal function. In dogs, nephrectomy is still the most common treatment for pyonephrosis; however, in the present report, a method for percutaneous ultrasound-guided drainage of the renal pelvis in dogs with pyonephrosis that does not require local or general anesthesia was described, and results of the procedure in 2 dogs were reported. Briefly, dogs were positioned in lateral recumbency with the affected side up, and skin overlying the affected kidney was aseptically prepared. The dilated renal pelvis was punctured percutaneously, under ultrasound guidance, with a 22-gauge needle, and a sample of material was obtained for analysis. The needle was then replaced with an IV catheter, and as much pus as possible was removed from the renal collecting system. A povidone iodine solution was then used to lavage the renal pelvis. Ultrasound-guided drainage and lavage of the renal pelvis was repeated daily until the renal pelvis was so small that it could no longer be punctured. Both dogs recovered and were reported by the owners to be healthy after the procedure.