Struvite ureterolithiasis associated with ureolytic bacterial pyelonephritis in a cat

A 2-year-old female spayed domestic shorthair cat with a 1-week history of lethargy and dysorexia was presented to a veterinary teaching hospital. Physical examination identified severe left nephromegaly, hyperthermia and abdominal pain. Abdominal ultrasound revealed a left ureteral dilation due to obstruction by a ureterolith, associated with marked subcapsular effusion. Urinalysis showed alkaline urine with crystals of struvite. Culture of urine from the renal pelvis and the urinary bladder was positive for Staphylococcus pseudintermedius. An infected struvite ureterolith due to the presence of urease-producing bacteria was suspected. The ureterolith was removed via ureterotomy and a temporary ureteral stent was positioned in an antegrade fashion. Results of infrared spectroscopy showed pure struvite urolithiasis. The stent was removed via cystoscopy 35 days after surgery. The cat was still doing well at the 6-month follow-up.

To the best of the authors' knowledge, this is the first case of a struvite ureterolith due to ureolytic pyelonephritis in a cat.