2026 ICD-10-CM Diagnosis Code T80.82XAComplication of immune effector cellular therapy, initial encounter

ICD-10-CM Codes›S00–T88›T80-T88›T80

ICD-10-CM T80.82XA
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

T80.82XA is a billable ICD-10-CM diagnosis code for complication of immune effector cellular therapy, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. 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 acute intoxication. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Complication of other surgical or medical care, injury, initial encounter.

Code Identity

ICD-10-CM Code
T80.82XA
Billable Status
Yes — Valid for Submission
Code Describes
Complication of immune effector cellular therapy, initial encounter
Short Description
Complication of immune effector cellular therapy, init
Parent Code
T80.82
Complication of immune effector cellular therapy

Code Classification

ChapterS00–T88Injury, poisoning and certain other consequences of external causes
SectionT80-T88Complications of surgical and medical care, not elsewhere classified
CategoryT80Complications following infusion, transfusion and therapeutic injection
This CodeT80.82XAComplication of immune effector cellular therapy, initial encounter

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute intoxication
  • Cytokine release syndrome
  • Cytokine release syndrome due to chimeric antigen receptor T-cell immunotherapy
  • Immune effector cell-associated neurotoxicity syndrome
  • Immune system complication of procedure

Coding GuidelinesGuidance

The appropriate 7th character is to be added to each code from block Complications following infusion, transfusion and therapeutic injection (T80). Use the following options for the applicable episode of care:

  • A - initial encounter
  • D - subsequent encounter
  • S - sequela

Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.

Clinical ClassificationClinical

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

CCSR INJ037
Complication of other surgical or medical care, injury, initial encounter
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Cytokine Release Syndrome

    a severe immune reaction characterized by excessive release of cytokines. symptoms include dyspnea; fever; headache; hypotension; nausea; rash; tachycardia; hypoxia; hyperferritinemia, and multiple organ failure. it is associated with viral infections, sepsis; autoimmune diseases and a variety of factors used in immunotherapy.

Code History & ChangesHistory

Replacement T80.82XA replaces the following previously assigned code(s):

  • T80.89XA - Oth comp fol infusion, transfuse and theraputc inject, init
FY 2022AddedAdded to the ICD-10-CM code setEffective October 1, 2021.
FY 2023–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About T80.82XAOverview

Is T80.82XA (Complication of immune effector cellular therapy) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report complication of immune effector cellular therapy, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What does the 7th character A in T80.82XA mean?

The final character A marks the initial encounter: use it while the patient is receiving active treatment for complication of immune effector cellular therapy, such as an emergency visit or first evaluation.

What MS-DRG does T80.82XA group to?

When complication of immune effector cellular therapy, initial encounter 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] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.