Kidney cysts are spherical pockets of fluid that form in the kidneys. Although occasionally associated with serious diseases, they are usually benign and seldom cause complications (simple kidney cysts). They are sometimes detected during imaging conducted to diagnose an unrelated condition; if they have no symptoms, they usually require no treatment.
Simple kidney cysts usually have no symptoms; if they grow large enough, symptoms may include:
- Dull local pain
- Upper abdominal pain
The cause of simple kidney cysts is unknown. Although they may occur at any time, the risk increases with age.
Simple kidney cysts are usually diagnosed through imaging – ultrasound, computerized tomography (CT), of magnetic resonance imaging (MRI). Once a cyst has been found, you may be given a blood test to determine whether it is impairing kidney function.
Usually, a simple kidney cyst has no symptoms, does not interfere with kidney function, and requires no treatment. You may be advised to have an imaging test periodically to see if the cyst is growing.
If the cyst has symptoms, treatments include:
- Puncturing the cyst with a long, thin, needle; draining it; and filling it with alcohol.
- Surgery to remove the cyst. A surgeon makes a few small incisions, and inserts a video camera and special tools to drain the cyst and remove or burn away its walls.