10/09/2025
This sweet cat came in with lethargy and difficulty urinating and on ultrasound, we found something unexpected: a perinephric pseudocyst.
A perinephric pseudocyst is a collection of fluid trapped between the kidney capsule and the kidney itself.
It isn’t a “true cyst” asthere’s no epithelial lining, instead, it forms when fluid slowly leaks and builds up, stretching the capsule and compressing the kidney tissue.
These are rare findings, most often seen in older cats, and may be associated with chronic kidney disease, inflammation, or hypertension.
Some cats show no symptoms, while others develop abdominal distention, discomfort, or urinary changes like in this case.
We drained the cyst to provide temporary relief and reduce pressure on the kidney.
However, surgery (capsulectomy) is often needed for a more permanent fix, since the fluid tends to return.
Every patient is different, our focus is always on restoring comfort, protecting kidney function, and improving quality of life.
