2026 ICD-10-CM Diagnosis Code D84.822Immunodeficiency due to external causes

ICD-10-CM Codes›D50–D89›D80-D89›D84

ICD-10-CM D84.822
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

D84.822 is a billable ICD-10-CM diagnosis code for immunodeficiency due to external causes. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 814 through 816. Coders also document this condition as immunodeficiency due to radiotherapy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Immunity disorders.

Code Identity

ICD-10-CM Code
D84.822
Billable Status
Yes — Valid for Submission
Code Describes
Immunodeficiency due to external causes
Short Description
Immunodeficiency due to external causes
Same as the full description in the CMS dataset.
Parent Code
D84.82
Immunodeficiency due to drugs and external causes

Code Classification

ChapterD50–D89Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
SectionD80-D89Certain disorders involving the immune mechanism
CategoryD84Other immunodeficiencies
This CodeD84.822Immunodeficiency due to external causes

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Immunodeficiency due to radiotherapy

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Code Also

  • , if applicable, radiological procedure and radiotherapy Y84.2

Use Additional Code

  • code for external cause such as:
  • exposure to ionizing radiation W88

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Immunodeficiency
      • due to
        • external causes

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR BLD008
Immunity disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

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 D84.822 replaces the following previously assigned code(s):

  • D84.8 - Other specified immunodeficiencies
FY 2021AddedAdded to the ICD-10-CM code setEffective October 1, 2020.
FY 2022–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About D84.822Overview

Is D84.822 (Immunodeficiency due to drugs and external causes) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report immunodeficiency due to external causes on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does D84.822 group to?

When immunodeficiency due to external causes is the principal diagnosis on an inpatient stay, it groups to MS-DRG 814, 815, 816, with relative weights from 0.6320 to 2.1267 depending on complications. Higher weights mean higher Medicare reimbursement.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.