N18.80: Unilateral chronic impairment of renal function

One of your two kidneys is damaged and its function is limited.

This is also referred to as renal insufficiency.

There are normally 2 kidneys in the body. They filter blood and create urine. They thus help to detoxify the body. Furthermore, the kidneys regulate the blood pressure and salt content in the blood, among other things.

If one kidney’s function is limited, it can no longer perform its tasks properly. One result of this may be that your blood pressure is too high. You may also feel weaker than usual. If both kidneys stop being able to produce enough urine between them, you excrete little urine. Too much fluid then remains in the body. This fluid can then collect in the legs, for example.

If both kidneys together can no longer function properly, certain substances can also accumulate in the body. These substances are normally excreted in the urine. The body can be damaged by these substances. You may get tired quickly and find it difficult to concentrate.

The kidneys also produce messenger substances. With kidney disease, there may be insufficient production of messengers. This can impact on the body in many ways. For example, the bones may become less solid. The salt content and acid content in your blood may also change.

Additional indicator

On medical documents, the ICD code is often appended by letters that indicate the diagnostic certainty or the affected side of the body.

  • G: Confirmed diagnosis
  • V: Tentative diagnosis
  • Z: Condition after
  • A: Excluded diagnosis
  • L: Left
  • R: Right
  • B: Both sides

Further information


This information is not intended for self-diagnosis and does not replace professional medical advice from a doctor. If you find an ICD code on a personal medical document, please also note the additional indicator used for diagnostic confidence.
Your doctor will assist you with any health-related questions and explain the ICD diagnosis code to you in a direct consultation if necessary.


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