Kidney cysts are rounded sacs usually filled with fluid. There are two types of cyst – simple and complex.
- Simple kidney cysts
Simple kidney cysts are benign and are common in the older population. Around one half of the population in their 50’s are thought to have a kidney cyst. Usually, it is difficult to know if you have cysts, as there are rarely physical symptoms. Most often the cysts would be discovered incidentally, during a test or scan for something else. Infrequently, a simple cyst could be painful if it is large and pressing on another organ. A cyst can also become infected and cause fever, pain and tenderness. Treatment for a simple kidney cyst is only required if it becomes infected or if it affects the function of the kidney or another organ.
- Complex kidney cysts
Complex cysts can potentially be cancerous/malignant. A complex cyst can have a more irregular shape than a simple cyst, or other irregularities such as a thicker wall. A scan may show that a complex cyst has features that suggest cancer. Such a cyst should be carefully evaluated as it may be best to remove it.
With BHD syndrome, it is possible to have many cysts. While these are most likely not cancerous, it is necessary to be monitored regularly to detect any cancer early and begin treatment as soon as possible.
Publication date: September 2012
Review date: September 2015