Simple kidney cysts may develop due to the obstruction of tubules, diverticula sac detachment, or insufficient blood supply to the kidneys, notes the National Institute of Diabetes and Digestive and Kidney Diseases. Kidney cysts occur when nephron tubules enlarge and fill with fluid, according to Cleveland Clinic.
The cause of simple kidney cysts remains unknown, but researchers believe that the condition develops if the surface layer of a kidney becomes weak and forms a pouch, explains the Mayo Clinic. Eventually, fluid accumulates in the pouch, which detaches and forms a cyst. The condition may also develop if a substance blocks the tubules that collect urine within the kidneys, explains the NIDDK. Simple kidney cysts are not dangerous, although doctors associate the large and irregular cysts with cancer, says the Cleveland Clinic.
Simple kidney cysts do not appear to be genetic, according to WebMD. However, the chance of developing kidney cysts is higher in men and the elderly. About half of all people aged 50 and above have at least one simple kidney cyst, although the number of cysts increases as one gets older, explains the Cleveland Clinic. Simple kidney cysts are not preventable, but drinking plenty of water and taking less sodium may reduce the risk, advises the Cleveland Clinic.