The cause of kidney cysts is not clear, but medical professionals theorize that the cysts develop when the kidney's surface layer forms a pouch and weakens, according to Mayo Clinic. Cysts develop when the pouch fills with fluid and detaches from the surface layer of the kidneys.
Serious disorders, such as polycystic kidney disease, frequently lead to kidney cysts, but many kidney cysts arise without an apparent etiology. These are known as simple kidney cysts.
Age and gender are considerable risk factors for the development of kidney cysts, explains WebMD. Approximately half of people over age 50 commonly develop one or more cysts in the kidneys. The size of the kidney cysts can also increase as people age.
Most people do not develop symptoms with kidney cysts, according to WebMD. In extreme cases, kidney cysts impair kidney function, cause bleeding and cause pain in the back, side or upper abdomen. Some patients may experience fever and chills if an infection develops.
Physicians detect kidney cysts with an ultrasound, explains WebMD. If pain or kidney complications do not exist, treatment is not necessary. For patients who experience symptoms, or if the cysts impact kidney function, physicians typically puncture the cyst with a long needle and drain the fluid in the cyst. The empty pouch is then filled with an alcohol-based solution to harden the tissues and prevent future cysts from developing.