2027 ICD-10-CM Diagnosis Code D71.9Functional disorders of polymorphonuclear neutrophils, unspecified
ICD-10-CM Codes›D50–D89›D70-D77›D71
- Billable — Valid for Submission
- Risk Adjusts — HCC 115
- Chronic Condition
D71.9 is a billable ICD-10-CM diagnosis code for functional disorders of polymorphonuclear neutrophils, unspecified. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 808 through 810. Coders also document this condition as functional disorder of polymorphonuclear neutrophil. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Diseases of white blood cells.
For Medicare Advantage risk adjustment, D71.9 maps to CMS-HCC Category 115 (Specified Immunodeficiencies and White Blood Cell Disorders) under the V28 model, adding a risk factor of about 0.565 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
D71.9 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Functional disorder of polymorphonuclear neutrophil
- Heritable disorder of neutrophil function
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to D71.9: its own notes plus those printed at Chapter 3. A note printed at a category, block or chapter applies to every code under it.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may 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)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name D71.9, its category, or a range that includes it.
Excludes1 1
These codes carry an Excludes1 note naming D71.9: they are not reported together with it, unless the two conditions are unrelated.
- Block D80-D89 Certain disorders involving the immune mechanismfunctional disorders of polymorphonuclear neutrophils (D71-) names D71-, which includes this code
Excludes2 2
These codes carry an Excludes2 note naming D71.9: its condition is not part of those codes, and both may be reported when the patient has both.
- Block L20-L30 Dermatitis and eczemachronic (childhood) granulomatous disease (D71-) names D71-, which includes this code
- Block R70-R79 Abnormal findings on examination of blood, without diagnosis
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Disorder (of) See Also: Disease;
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Immune System and Disorders
Your immune system is a complex network of cells, tissues, and organs. Together they help the body fight infections and other diseases.
The full article covers:
- What is the immune system?
- What are the parts of the immune system?
- How does the immune system work?
- What are the types of immunity?
- What can go wrong with the immune system?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Code History & ChangesHistory
Replacement D71.9 replaces the following previously assigned code(s):
- D71 - Functional disorders of polymorphonuclear neutrophils
Questions About D71.9Overview
What is the ICD-10 code for functional disorders of polymorphonuclear neutrophils, unspecified?
The ICD-10-CM code for functional disorders of polymorphonuclear neutrophils, unspecified is D71.9 (sometimes written as D719). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is D71.9 (Functional disorders of polymorphonuclear neutrophils) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report functional disorders of polymorphonuclear neutrophils, unspecified on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does D71.9 group to?
When functional disorders of polymorphonuclear neutrophils, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 808, 809, 810, with relative weights from 1.0749 to 2.1706 depending on complications. Higher weights mean higher Medicare reimbursement.
What HCC is D71.9?
D71.9 (functional disorders of polymorphonuclear neutrophils, unspecified) maps to CMS-HCC Category 115 (Specified Immunodeficiencies and White Blood Cell Disorders), commonly written as HCC 115, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.
Does D71.9 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, D71.9 adds a risk adjustment factor of about 0.565 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.302 to 0.692 depending on the payment segment). A more severe related category (HCC 114) supersedes it when both are reported. See the full factor table on the HCC 115 category page.
