What cause sis in the kidney and what are sis?

Cysts in the kidney, known as renal cysts, are fluid-filled sacs that can develop on or within the kidneys. They can be caused by various factors, including genetic conditions (like polycystic kidney disease), age-related changes, or kidney injuries. Most renal cysts are benign and asymptomatic, but larger or multiple cysts may lead to complications or discomfort. Regular monitoring may be necessary to ensure they do not interfere with kidney function.