D83.9

HCC Category Mapping

What This Code Means

A common variable immunodeficiency where the immune system is weakened, but the specific type of immune cell or function problem has not been identified.

Coding Tips

• •This is a default code for CVID; use only when immunological testing results are unavailable or inconclusive
• •Encourage providers to complete immunological workup to assign a more specific D83 code

Clinical Significance

Common variable immunodeficiency, unspecified, indicates a confirmed diagnosis of common variable immunodeficiency where the specific immunological subtype has not been determined through testing. Common variable immunodeficiency is the most frequently diagnosed symptomatic primary immunodeficiency in adults, requiring lifelong immunoglobulin replacement therapy and monitoring for complications including malignancy, autoimmune disease, and granulomatous inflammation.

Documentation Requirements

• ✓Documentation must include at least two immunoglobulin classes significantly below normal for age, poor response to vaccine challenge, exclusion of other causes of hypogammaglobulinemia, and clinical manifestations.
• ✓Document the reason why specific subcategorization (B-cell, T-cell, or autoantibody-mediated) cannot be determined and the plan for further immunological characterization if applicable.

Commonly Confused Codes