2021 ICD-10-CM Code D89.89

Other specified disorders involving the immune mechanism, not elsewhere classified

Version 2021
Replaced Code
Billable Code
MS-DRG Mapping

Valid for Submission

D89.89 is a billable diagnosis code used to specify a medical diagnosis of other specified disorders involving the immune mechanism, not elsewhere classified. The code D89.89 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

The ICD-10-CM code D89.89 might also be used to specify conditions or terms like antibody-mediated cytolysis, anti-human leukocyte antigen hyperimmunization, autoimmune disorder of bilateral inner ears, autoimmune disorder of inner ear, autoimmune enteropathy , autoimmune enteropathy, etc.

ICD-10:D89.89
Short Description:Oth disrd involving the immune mechanism, NEC
Long Description:Other specified disorders involving the immune mechanism, not elsewhere classified

Code Classification

Replaced Code

This code was replaced in the 2021 ICD-10 code set with the code(s) listed below. The National Center for Health Statistics (NCHS) has published an update to the ICD-10-CM diagnosis codes which became effective October 1, 2020. This code was replaced for the FY 2021 (October 1, 2020 - September 30, 2021).


  • D89.40 - Mast cell activation, unspecified
  • D89.40 - Mast cell activation, unspecified
  • D89.41 - Monoclonal mast cell activation syndrome
  • D89.41 - Monoclonal mast cell activation syndrome
  • D89.42 - Idiopathic mast cell activation syndrome
  • D89.42 - Idiopathic mast cell activation syndrome
  • D89.43 - Secondary mast cell activation
  • D89.43 - Secondary mast cell activation
  • D89.49 - Other mast cell activation disorder
  • D89.49 - Other mast cell activation disorder
  • D89.831 - Cytokine release syndrome, grade 1
  • D89.832 - Cytokine release syndrome, grade 2
  • D89.833 - Cytokine release syndrome, grade 3
  • D89.834 - Cytokine release syndrome, grade 4
  • D89.835 - Cytokine release syndrome, grade 5
  • D89.839 - Cytokine release syndrome, grade unspecified

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code D89.89:


Type 1 Excludes

Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code D89.89 are found in the index:

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Convert D89.89 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code D89.89 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Immune System and Disorders

Your immune system is a complex network of cells, tissues, and organs that work together to defend against germs. It helps your body to recognize these "foreign" invaders. Then its job is to keep them out, or if it can't, to find and destroy them.

If your immune system cannot do its job, the results can be serious. Disorders of the immune system include

NIH: National Institute of Allergy and Infectious Diseases


[Learn More in MedlinePlus]

Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)