Important Renal Cysts Information

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Renal Cyst Overview

Studies have shown that 4 out of 10 people aged 60 and above may develop renal cysts. Renal cysts are sacs filled with fluid which form in the surface or inside the kidneys. It is said that the cause may be attributed to defects in the renal collecting tubules. The renal collecting tubules are important kidney structures that are responsible in the transport of urine inside the kidneys. Some patients may have solitary or multiple renal cysts. Below are additional renal cysts information which deals with the symptoms, causes, diagnosis and treatment of such condition.

Causes and Symptoms

Most cases of renal cysts are discovered by accident due to the fact that no noticeable symptoms are usually felt by affected individuals. When symptoms do occur, patients often manifest with flank pain, frequent urge to urinate and difficulty urinating. They may also notice a tinge of blood in the urine. When their urine is analyzed under the microscope, red blood cells may be seen, a condition is known as hematuria. Patients with renal cysts may also feel bloated or full even without having a meal. Such feelings of fullness may become frequent as the cysts continue to grow in size. Fever and nausea may also be present.

Patients whose renal cysts continue to grow may experience pain as the cyst or cysts may impinge on neighboring structures. In some cases, the cyst can bleed or become infected.


Solitary cysts are the ones which are usually detected by accident through imaging studies done for other medical conditions. While generally considered insignificant, solitary cysts may also cause hematuria. On the other hand, multiple renal cysts are more common among patients with chronic kidney disease, especially those who undergo dialysis regularly. Most acquired renal cysts can potentially cause renal cell carcinoma. Patients are frequently required to be screened using CT scan or ultrasonography. An MRI or magnetic resonance imaging may also be done. When found, these renal cysts are generally classified as either malignant or benign according to the Bosniak classification system.


When renal cysts are considered benign and does not cause discomfort to the patients, they are often left untreated. Those benign cysts which cause symptoms are usually drained with the use of a laparoscopic procedure.

In cases where the renal cysts are found to be malignant, a surgical procedure is often needed for its removal. The procedure is known as partial nepherectomy. Partial nepherectomy involves removal of the diseased part of the kidneys while leaving the healthy tissues in placed. In patients with localized cysts or tumors, partial nephrectomy frequently offers some protection against the recurrence of cancer, as well as avoids scarring of the kidneys.

Other Renal Cysts Information

  • Benign renal cysts which can grow larger may also need surgery for their removal.

  • In a few cases, renal cyst can also result in kidney function impairment.


MERCK: Acquired Renal Cysts,

NYU: Renal Cysts,

NKUDIC: Simple Kidney Cysts,