ICD-10 Code D80.9 – Immunodeficiency with predominantly antibody defects, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D80.9 – Immunodeficiency with predominantly antibody defects, unspecified
What it is
D80.9 identifies an unspecified primary immunodeficiency in which antibody production is impaired. Use it when the record confirms a predominantly antibody defect but does not name a more specific type.
Clinical signs
Clinical features vary; refer to documentation. Commonly noted findings include recurrent bacterial infections, especially of the sinopulmonary tract, and poor immune response suggesting impaired humoral immunity.
When to use this code
Use D80.9 when the provider documents an antibody deficiency or humoral immunodeficiency and no further subtype is stated. It also fits when the chart supports a primary immunodeficiency, but the exact disorder remains unspecified.
Do not assume a more specific code from test results alone. If the record names a defined antibody defect, such as a particular immunoglobulin deficiency, code that condition instead.
Do not use for
Do not use D80.9 for secondary immunodeficiency, acquired immune suppression, or nonimmune causes of recurrent infection. Check documentation if the diagnosis is a specific antibody disorder.
Coding tip
Query for the exact immunodeficiency type when the note says only “immune deficiency” or “antibody defect.”