Case Of the Month

Bilateral Ureterolithiasis and Hydronephrosis in a 10-Year-Old Female Spayed DLH Cat: Our Case Of the Month February 2018

The patient presented for pain in the area of the kidneys, dehydration, and anorexia with increased renal values. The patient initially improved after treatment with I.V. fluids, but the symptoms returned 5 days later. Cerenia, SQ fluids, and buprenorphine were added to the treatment plan. Preliminary blood chemistry revealed BUN 128, creat. 7.6 which improved to a BUN of 29 and a creat. of 2.2; all other parameters were WNL.

DX

Bilateral ureterolithiasis present in the right and left ureters with secondary proximal ureter dilation. This is consistent with partial to complete obstruction. Marked hydronephrosis with loss of normal renal medulla parenchyma in the left kidney and merging to mild hydronephrosis with mild loss of normal renal medulla parenchyma of the right kidney. Focal nephrolithiasis was present within the dilated renal pelvis and medulla of the right kidney.

Outcome

The bilateral ureteroliths are likely causing partial to complete obstruction of the right and left ureter with hydronephrosis in the right and left kidney. Smaller left kidney size with marked hydronephrosis suggests more chronic disease in the left kidney. The functionality of the left kidney is highly questionable. The pain exhibited by the patient is likely associated with the ureterolithiasis and development of hydronephrosis. Treatment options would likely be centered around preserving functionality of the right kidney. Referral in this case for possible surgical options such as ureterolith removal or possible stent placement is recommended. Placement of a subcutaneous ureteral bypass device (SUB) is also an option in this case. If referral is not an option then conservative treatment may include continued IV fluids, pain medications and an Alpha blocker such as Prazosin to try to get the ureteroliths to move. This may or may not be possible. Therefore, guarded prognosis is warranted in this case. Systemic blood pressure may also be considered due to the degree of renal disease.Unfortunately, due to quality of life concerns and a poor prognosis the patient was humanely euthanized.

Image Interpretation

The left kidney was small in size with mildly irregular margination. Moderate hydronephrosis was present with obliteration of the renal medulla parenchyma. Indistinct corticomedullary differentiation was present between the cortex and remaining medulla. The hydronephrosis in the left kidney measured 1.6 x 0.8 cm and extended into the proximal left ureter. Left ureter dilation measured 0.3 cm. A focal, echogenic ureterolith with acoustic shadowing was present within the lumen of the left ureter and measured 0.3 cm in diameter and was located approximately 0.5 cm from the renal pelvis. The left kidney measured 2.3 cm in length. The right kidney presented normal in size and margination with indistinct corticomedullary distinction and emerging mild hydronephrosis was present. Mild obliteration of the right renal medulla parenchyma was noted. The hydronephrosis in the right kidney measured 0.9 x 0.8 cm and extended into the right ureter. Right ureter dilation measured 0.3 cm. A focal, echogenic ureterolith with distal acoustic shadowing was located approximately 2.0 cm from the right kidney renal pelvis.