D84.821
BillableImmunodeficiency due to drugs
HCC Category Mapping
V24HCC 47 — Disorders of Immunity
0.472ESRDHCC 47 — Disorders of Immunity
0.000RxHCCHCC 99 — Immunodeficiencies
0.000What This Code Means
A weakened immune system caused by medications the patient is taking, such as chemotherapy, immunosuppressants, or corticosteroids.
Coding Tips
- •Document the specific medication causing the immunodeficiency in the medical record
- •Code the underlying condition being treated with the immunosuppressive medication as well
Clinical Significance
Immunodeficiency due to drugs represents iatrogenic immunosuppression caused by medications including chemotherapy agents, corticosteroids, disease-modifying antirheumatic drugs, calcineurin inhibitors, and biologic agents such as anti-tumor necrosis factor therapies and rituximab. This condition reflects the increased infection risk and immune dysfunction that occurs as a direct consequence of pharmacological treatment.
Documentation Requirements
- ✓Documentation must identify the specific medication(s) causing immunodeficiency, the underlying condition being treated, evidence of immune impairment (opportunistic infections, low immunoglobulin levels, lymphopenia), and whether the immunosuppression is intentional (transplant rejection prevention) or an adverse effect.
- ✓Include appropriate adverse effect or long-term medication use codes (T-codes or Z-codes).
Use Additional Code
- code for adverse effect if applicable, to identify adverse effect of drug (T36-T50 with fifth or six character 5)
- code, if applicable, for associated long term (current) drug therapy drug or medication such as:
- long term (current) drug therapy systemic steroids (Z79.52)
- other long term (current) drug therapy (Z79.899)