ICD-10 Code for Immunodeficiency

The default ICD-10-CM 2027 code for immunodeficiency is D84.9 – Immunodeficiency, unspecified. More specific codes depend on the details documented, as listed in the official index (33 codes, 33 billable).

Main code: D84.9 – Immunodeficiency, unspecified
Billable: Yes

Index entries for Immunodeficiency

with
- adenosine-deaminase deficiency – D81.30 – see also Deficiency, adenosine deaminase
- antibody defects – D80.9
  - specified type NEC – D80.8
- hyperimmunoglobulinemia – D80.6
- increased immunoglobulin M (IgM) – D80.5
- major defect – D82.9
  - specified type NEC – D82.8
- partial albinism – D82.8
- short-limbed stature – D82.2
- thrombocytopenia and eczema – D82.0
antibody with
- hyperimmunoglobulinemia – D80.6
- near-normal immunoglobulins – D80.6
autosomal recessive, Swiss type – D80.0
combined – D81.9
- biotin-dependent carboxylase – D81.819
  - biotinidase – D81.810
  - holocarboxylase synthetase – D81.818
  - specified type NEC – D81.818
- severe (SCID) – D81.9
  - with
    - low or normal B-cell numbers – D81.2
    - low T- and B-cell numbers – D81.1
    - reticular dysgenesis – D81.0
- specified type NEC – D81.89
common variable – D83.9
- with
  - abnormalities of B-cell numbers and function – D83.0
  - autoantibodies to B- or T-cells – D83.2
  - immunoregulatory T-cell disorders – D83.1
- specified type NEC – D83.8
due to
- conditions classified elsewhere – D84.81
- drugs – D84.821
- external causes – D84.822
- medication (current or past) – D84.821
following hereditary defective response to Epstein-Barr virus (EBV) – D82.3
selective, immunoglobulin
- A (IgA) – D80.2
- G (IgG) (subclasses) – D80.3
- M (IgM) – D80.4
severe combined (SCID) – D81.9
- due to adenosine deaminase deficiency – D81.31
specified type NEC – D84.89
X-linked, with increased IgM – D80.5

How to choose the right code

Start with the main term, then pick the indented subterm that matches the documentation (type, cause, site, laterality, episode of care). Always confirm the code in the tabular list: follow its Excludes1/Excludes2, “code first” and “use additional code” notes, and add a 7th character where required.

Source: CDC/NCHS ICD-10-CM FY2027 alphabetic index.