D89.8: Other specified disorders involving the immune mechanism, not elsewhere classified

Your immune system has a disorder.

There are various kinds of defense cells (immune cells) in the body. Specific immune cells produce antibodies in the blood. The antibodies cling to pathogens and foreign substances in the blood, for example. This allows the antibodies to make the pathogens and foreign substances visible to the immune system. The immune system helps the body to fight and eliminate diseases and foreign substances.

When the immune system has a disorder, it may not create the right antibodies, for example. The immune system may also produce too many or the wrong antibodies, or certain defense cells may not be produced properly.

When there is a disorder in the immune system, the body finds it harder to protect against pathogens. So you become ill more easily. Your immune system may also attack your own body or inflammations can occur around the body. Then you can get fever, diarrhea or inflammations of the airways, for example. If the disorder is congenital, it can delay physical and mental development.

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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