Kidney Cyst Symptoms: What You Need to Know About Kidney Cyst Signs and Symptoms

A cyst is a fluid (water, blood, or pus-filled) sac that can form on or within one or both kidneys. These cysts are typically round or oval in shape and may vary in size from very small, barely visible on imaging tests, to quite large. Kidney cysts are relatively common, especially as people age, and they can be categorized into two main types: simple cysts and complex cysts.

Simple Kidney Cysts:

  • Simple cysts are the most common type and are typically benign (non-cancerous).
  • They are usually filled with clear fluid and have thin, well-defined walls.
  • Simple kidney cysts are often asymptomatic and don’t cause noticeable symptoms.
  • These cysts are usually discovered incidentally during imaging tests like ultrasound, CT scans, or MRI for other medical reasons.
  • Simple cysts generally do not require treatment unless they are causing symptoms or complications.

Complex Kidney Cysts:

  • Complex cysts are less common and can be more concerning.
  • They may have thicker walls and contain solid elements, making them more challenging to distinguish from potentially cancerous growths.
  • Complex cysts may require further evaluation through additional imaging or other tests to determine whether they are benign or cancerous.

It’s important to note that most kidney cysts are benign and do not lead to kidney cancer. Simple kidney cysts, in particular, are typically harmless and don’t require treatment. However, if you have a complex cyst, you must consult a urologist for a proper diagnosis and appropriate management. Additionally, individuals with a family history of kidney cysts or certain genetic conditions, such as polycystic kidney disease (PKD), may be at a higher risk of developing kidney cysts and should discuss their risk factors and screening options with a healthcare provider.

Kidney Cysts


Kidney cysts, particularly simple cysts, often do not cause noticeable symptoms and are usually discovered incidentally during imaging tests for other medical reasons. However, in some cases, kidney cysts can cause symptoms or complications. The symptoms associated with kidney cysts, when they do occur, may include: