D89.3: Immune reconstitution syndrome

Your immune system has reacted unexpectedly to the treatment for another condition.

The immune system protects the body from pathogens and foreign substances. The immune system can also destroy cells in the body that have pathologically changed.

Various conditions cause the immune system to stop working properly. So you have been treated to restore your immune system. Your immune system has reacted to this treatment in an unexpected way.

Though the treatment is effective, the condition can get worse because of the immune system’s reaction. For example, you can get a fever or a skin rash. You may get illnesses due to pathogens or existing conditions may get worse. The immune system may also attack the body’s own tissue, or malignant tissue can form in the body.

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.


Provided by the non-profit organization “Was hab’ ich?” gemeinnützige GmbH on behalf of the Federal Ministry of Health (BMG).