2026 ICD-10-CM Diagnosis Code B26.81Mumps hepatitis

ICD-10-CM CodesA00–B99B25-B34B26

ICD-10-CM B26.81
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

B26.81 is a billable ICD-10-CM diagnosis code for mumps hepatitis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 441 through 443. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Hepatitis and Viral infection.

Code Identity

ICD-10-CM Code
B26.81
Billable Status
Yes — Valid for Submission
Code Describes
Mumps hepatitis
Short Description
Mumps hepatitis
Same as the full description in the CMS dataset.
Parent Code
Mumps with other complications

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB25-B34Other viral diseases
CategoryB26Mumps
This CodeB26.81Mumps hepatitis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Mumps hepatitis

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.

    • Hepatitis
      • in (due to)
        • mumps
    • Mumps
      • hepatitis

Clinical ClassificationClinical

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

CCSR INF007
Hepatitis
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR INF008
Viral infection
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Hepatitis

Hepatitis is inflammation of the liver. Inflammation is swelling that happens when tissues of the body are injured or infected. It can damage your liver. This swelling and damage can affect how well your liver functions.

The full article covers:

  • What is hepatitis?
  • What causes hepatitis?
  • How is viral hepatitis spread?
  • Who is at risk for hepatitis?
  • What are the symptoms of hepatitis?
  • What other problems can hepatitis cause?
  • How is hepatitis diagnosed?
  • What are the treatments for hepatitis?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert B26.81 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
072.71 Mumps hepatitis
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About B26.81Overview

Is B26.81 (Mumps with other complications) a billable code?

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

What MS-DRG does B26.81 group to?

When mumps hepatitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 441, 442, 443, with relative weights from 0.6997 to 1.7947 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of B26.81?

Under the General Equivalence Mappings, mumps hepatitis converts to ICD-9-CM 072.71 (mumps hepatitis). The mapping is a direct match.

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.