D84.81 — Immunodeficiency due to conditions classified elsewhere
Is D84.81 billable?
Yes — D84.81 is billable for FY2027. D84.81 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. D84.81 may be submitted for encounters from October 1, 2026 through September 30, 2027.
D84.81 at a glance
| Code | D84.81 |
|---|---|
| Description | Immunodeficiency due to conditions classified elsewhere |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
What Medicare edits apply to D84.81?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name D84.81 directly.
This code describes a manifestation of an underlying disease. The underlying condition must be sequenced before it, so it can never be the principal or first-listed diagnosis.
Which MS-DRGs does D84.81 group to?
D84.81 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, D84.81 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is D84.81 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to D84.81. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Immunodeficiency › due to › conditions classified elsewhere
Excludes1 — never code together
The conditions below can never be reported together with D84.81 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Code first
The underlying condition below must be sequenced before D84.81. D84.81 describes a manifestation and cannot be the principal or first-listed diagnosis.
Excludes1 — never code together — inherited from D80-D89
The conditions below can never be reported together with D84.81 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 D84.81, but a patient may have both at the same time. When documentation supports it, D84.81 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 D84.81, but a patient may have both at the same time. When documentation supports it, D84.81 and the excluded code may both be reported.
- human immunodeficiency virus [HIV] disease (B20)
How long has D84.81 existed?
D84.81 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.