Version 2024

2024 ICD-10-CM Diagnosis Code D81

Combined immunodeficiencies

ICD-10-CM Code:
D81
ICD-10 Code for:
Combined immunodeficiencies
Is Billable?
Not Valid for Submission
Code Navigator:

Code Classification

  • Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
    (D50–D89)
    • Certain disorders involving the immune mechanism
      (D80-D89)
      • Combined immunodeficiencies
        (D81)

D81 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of combined immunodeficiencies. The code is not specific and is NOT valid for the year 2024 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Specific Coding Applicable to Combined immunodeficiencies

Non-specific codes like D81 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for combined immunodeficiencies:

  • Use D81.0 for Severe combined immunodeficiency [SCID] with reticular dysgenesis - BILLABLE CODE

  • Use D81.1 for Severe combined immunodeficiency [SCID] with low T- and B-cell numbers - BILLABLE CODE

  • Use D81.2 for Severe combined immunodeficiency [SCID] with low or normal B-cell numbers - BILLABLE CODE

  • D81.3 for Adenosine deaminase [ADA] deficiency - NON-BILLABLE CODE

  • Use D81.30 for Adenosine deaminase deficiency, unspecified - BILLABLE CODE

  • Use D81.31 for Severe combined immunodeficiency due to adenosine deaminase deficiency - BILLABLE CODE

  • Use D81.32 for Adenosine deaminase 2 deficiency - BILLABLE CODE

  • Use D81.39 for Other adenosine deaminase deficiency - BILLABLE CODE

  • Use D81.4 for Nezelof's syndrome - BILLABLE CODE

  • Use D81.5 for Purine nucleoside phosphorylase [PNP] deficiency - BILLABLE CODE

  • Use D81.6 for Major histocompatibility complex class I deficiency - BILLABLE CODE

  • Use D81.7 for Major histocompatibility complex class II deficiency - BILLABLE CODE

  • D81.8 for Other combined immunodeficiencies - NON-BILLABLE CODE

  • D81.81 for Biotin-dependent carboxylase deficiency - NON-BILLABLE CODE

  • Use D81.82 for Activated Phosphoinositide 3-kinase Delta Syndrome [APDS] - BILLABLE CODE

  • Use D81.89 for Other combined immunodeficiencies - BILLABLE CODE

  • Use D81.9 for Combined immunodeficiency, unspecified - BILLABLE CODE

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


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.
  • autosomal recessive agammaglobulinemia Swiss type D80.0

Patient Education


Immune System and Disorders

What is the immune system?

Your immune system is a complex network of cells, tissues, and organs. Together they help the body fight infections and other diseases.

When germs such as bacteria or viruses invade your body, they attack and multiply. This is called an infection. The infection causes the disease that makes you sick. Your immune system protects you from the disease by fighting off the germs.

What are the parts of the immune system?

The immune system has many different parts, including:

  • Your skin, which can help prevent germs from getting into the body
  • Mucous membranes, which are the moist, inner linings of some organs and body cavities. They make mucus and other substances which can trap and fight germs.
  • White blood cells, which fight germs
  • Organs and tissues of the lymph system, such as the thymus, spleen, tonsils, lymph nodes, lymph vessels, and bone marrow. They produce, store, and carry white blood cells.

How does the immune system work?

Your immune system defends your body against substances it sees as harmful or foreign. These substances are called antigens. They may be germs such as bacteria and viruses. They might be chemicals or toxins. They could also be cells that are damaged from things like cancer or sunburn.

When your immune system recognizes an antigen, it attacks it. This is called an immune response. Part of this response is to make antibodies. Antibodies are proteins that work to attack, weaken, and destroy antigens. Your body also makes other cells to fight the antigen.

Afterwards, your immune system remembers the antigen. If it sees the antigen again, it can recognize it. It will quickly send out the right antibodies, so in most cases, you don't get sick. This protection against a certain disease is called immunity.

What are the types of immunity?

There are three different types of immunity:

  • Innate immunity is the protection that you are born with. It is your body's first line of defense. It includes barriers such as the skin and mucous membranes. They keep harmful substances from entering the body. It also includes some cells and chemicals which can attack foreign substances.
  • Active immunity, also called adaptive immunity, develops when you are infected with or vaccinated against a foreign substance. Active immunity is usually long-lasting. For many diseases, it can last your entire life.
  • Passive immunity happens when you receive antibodies to a disease instead of making them through your own immune system. For example, newborn babies have antibodies from their mothers. People can also get passive immunity through blood products that contain antibodies. This kind of immunity gives you protection right away. But it only lasts a few weeks or months.

What can go wrong with the immune system?

Sometimes a person may have an immune response even though there is no real threat. This can lead to problems such as allergies, asthma, and autoimmune diseases. If you have an autoimmune disease, your immune system attacks healthy cells in your body by mistake.

Other immune system problems happen when your immune system does not work correctly. These problems include immunodeficiency diseases. If you have an immunodeficiency disease, you get sick more often. Your infections may last longer and can be more serious and harder to treat. They are often genetic disorders.

There are other diseases that can affect your immune system. For example, HIV is a virus that harms your immune system by destroying your white blood cells. If HIV is not treated, it can lead to AIDS (acquired immunodeficiency syndrome). People with AIDS have badly damaged immune systems. They get an increasing number of severe illnesses.


[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • 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. This was the first year ICD-10-CM was implemented into the HIPAA code set.