N18.1: Chronic kidney disease, stage 1

Your kidneys have had mild damage for a long time.

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.

When there is mild damage to the kidneys, it is known as early kidney disease. The kidneys can be damaged by long-term high blood pressure or elevated blood sugar, for example.

In the early stages of kidney disease, healthy areas of the kidneys can still ensure that kidney function is almost normally. Sufficient urine is still produced, for example. Therefore there are no or few symptoms. The urine may be paler than usual and foam up when urinating. You may also be thirstier than usual and have to urinate more frequently during the night. If the kidney disease gets worse, other symptoms can appear.

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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