D84.821 — Immunodeficiency due to drugs
Is D84.821 billable?
Yes — D84.821 is billable for FY2027. D84.821 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. D84.821 may be submitted for encounters from October 1, 2026 through September 30, 2027.
D84.821 at a glance
| Code | D84.821 |
|---|---|
| Description | Immunodeficiency due to drugs |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does D84.821 group to?
D84.821 sits in MDC 16 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 814Reticuloendothelial and Immunity Disorders with MCCmedical
- 815Reticuloendothelial and Immunity Disorders with CCmedical
- 816Reticuloendothelial and Immunity Disorders without CC/MCCmedical
As a secondary diagnosis, D84.821 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is D84.821 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to D84.821. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Immunodeficiency › due to › drugs
- Immunodeficiency › due to › medication
Use additional code
Report an additional code alongside D84.821 to fully describe the condition. D84.821 is sequenced first.
- 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)
Inclusion terms
Alternative wording in documentation that is classified to D84.821.
- Immunodeficiency due to (current or past) medication
Excludes1 — never code together — inherited from D80-D89
The conditions below can never be reported together with D84.821 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes2 — not included here — inherited from Chapter 3
The conditions below are not part of D84.821, but a patient may have both at the same time. When documentation supports it, D84.821 and the excluded code may both be reported.
- autoimmune disease (systemic) NOS (M35.9)
- certain conditions originating in the perinatal period (P00-P96)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- human immunodeficiency virus [HIV] disease (B20)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Excludes2 — not included here — inherited from D80-D89
The conditions below are not part of D84.821, but a patient may have both at the same time. When documentation supports it, D84.821 and the excluded code may both be reported.
- human immunodeficiency virus [HIV] disease (B20)
How long has D84.821 existed?
D84.821 first appears in FY2021 (FY2020 is not available, so it may have appeared then).
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.