Kidney lesions, or cysts, are detectable via a computerized tomography (CT) scan or an ultrasound, according to WebMD. Simple lesions often cause no symptoms in the patient unless they are very large or become infected.
A kidney lesion typically appears as a fluid-filled tissue abnormality on the surface of one or both kidneys, notes Mayo Clinic. Simple kidney cysts have no discernible cause and usually do not cause symptoms or serious health problems. Detection of the lesions is sometimes accidental, occurring during an MRI, CT scan or ultrasound for another purpose. Additional imaging tests are helpful in determining if the lesion is a simple cyst or a tumor.
When kidney cysts become overly large, they compress other abdominal organs, causing back or side pain, while infected lesions cause fever, explains WebMD. It is possible for cysts to bleed and, in rare cases, negatively impact kidney function.
A kidney cyst that causes no symptoms typically only requires observation, as stated by WebMD. If the cyst is large or infected, a doctor may use an ultrasound to guide a long needle through the body to rupture the cyst. Filling the empty lesion with an alcohol solution scars the tissue and inhibits recurrence.