Simple renal cysts are the most common cystic lesions found in the human kidney. They are usually oval to round, may be single or multiple, may occur on one or both sides, and are filled with clear fluid.
Key Takeaways
- Simple cysts are the most common cystic lesions found in the kidney and are usually harmless.
- They become more common with age and often cause no symptoms at all.
- Occasionally a cyst may cause pain, blood in the urine or, rarely, obstruction of the kidney.
Simple cysts are not connected to any other part of the kidney. Although they can appear at any time of life, they are rarely seen in children. In adults they are found increasingly with age: the incidence rises to around 20% by the age of 40 and can be as high as 50% after the age of 60. Cysts may or may not grow larger over time, though the total number of cysts can increase. There is no difference in frequency between men and women.
Clinical features
Most simple cysts cause no trouble at all, other than the natural anxiety they can create once a patient learns of them. They are usually discovered by chance during an ultrasound, CT scan or other imaging test carried out for another reason.
- Very occasionally, a cyst can cause symptoms and may need treatment. These symptoms can include an abdominal lump or pain, blood in the urine and, very rarely, high blood pressure.
- In rare cases, a cyst can obstruct the flow of urine from the kidney.
When further tests are needed
If there is any doubt about whether a cyst is truly simple, your urologist will arrange further imaging to classify the type of cyst more precisely and give you a clear answer. This helps distinguish a harmless simple cyst from the small number of cysts that need closer attention. To learn more about the warning sign of blood in the urine, you may find our article on blood in the urine helpful.
There is usually no cause for worry. Talk to your urologist, who will help you understand your diagnosis and reassure you about the next steps.
Every treatment plan starts with a proper assessment, so you only get the care your condition actually needs. If you have symptoms or a question about your health, book a consultation with Dr. Anish Gupta.