Ureteroliths

Ureteroliths are stones that form within the ureters—the narrow tubes that carry urine from each kidney down to the bladder. These stones may remain silent for some time, or they may partially or completely obstruct the flow of urine from one kidney, leading to a range of signs that can vary widely in how suddenly they appear. Owners often arrive here because their dog or cat has been vomiting, seems uncomfortable, has been straining to urinate, or has had blood noticed in the urine. In some cases, the stone is discovered during imaging performed for another reason, before any signs have developed. The clinical picture depends on whether the stone is causing obstruction, how complete that obstruction is, and whether infection or kidney injury has developed alongside it. This page explores the signals that may suggest a ureteral stone, the factors that contribute to stone formation and obstruction, the ways these stones are identified and assessed, and the range of approaches used to address them—from monitoring in stable cases to interventions that relieve obstruction when the kidney's function is at risk.