Just wondering if this is a significant finding in dogs or has anyone seen kidneys like this? Unlike the medullary rim sign in dogs and cats, is there a term for this sonographic appearance?
3 year old, FS, cavoodle was presented for repeated HGE. Blood work was unremarkable. Both kidneys were symmetrical in appearance, presenting a hypoechoic rim around the capsule.
Just wondering if this is a significant finding in dogs or has anyone seen kidneys like this? Unlike the medullary rim sign in dogs and cats, is there a term for this sonographic appearance?
3 year old, FS, cavoodle was presented for repeated HGE. Blood work was unremarkable. Both kidneys were symmetrical in appearance, presenting a hypoechoic rim around the capsule.
In humans, it is called ‘kidney sweat’ and could be a sign of renal failure–>
Perirenal lucency (“kidney sweat”): a new sign of renal failure.
Abstract
OBJECTIVE:This study describes a new sonographic finding in renal failure: perirenal lucency, which we call the “kidney sweat” sign.
MATERIALS AND METHODS:During 1 year at our institution, 502 renal sonograms were obtained. Sonography evaluated 330 patients with renal failure. All of the examinations were retrospectively analyzed.
RESULTS: An extracapsular hypoechoic rim was present in 47 (14%) of the 330 patients with renal failure. The finding, when present, was always bilateral. The hypoechoic rim was not present in the remaining 283 patients with renal failure. Forty (85%) of the 47 patients had kidneys that were hyperechoic compared with the liver. Twenty-eight (60%) of the 47 patients had kidneys that were hyperechoic compared with the spleen. In 15 (32%) of the 47 patients, the kidneys were small. Ascites was present in 11 (23%) of the 47 patients. Of the 283 patients with renal failure whose sonograms did not show the hypoechoic rim, 76 patients had normal sonographic findings. The remaining 207 patients with renal failure who did not show the kidney sweat sign had hydronephrosis, stones, cysts, echogenic kidneys, small kidneys, or ascites.
CONCLUSION: An extracapsular hypoechoic rim is found in patients with renal failure. We call this finding “kidney sweat.” We believe, but cannot currently prove, that the kidney sweat sign represents edema. It is an additional sonographic finding in patients with renal failure.