2026 ICD-10-CM Diagnosis Code B16.1Acute hepatitis B with delta-agent without hepatic coma

ICD-10-CM Codes›A00–B99›B15-B19›B16

ICD-10-CM B16.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

B16.1 is a billable ICD-10-CM diagnosis code for acute hepatitis B with delta-agent without hepatic coma. 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. Coders also document this condition as acute hepatitis B with hepatitis D. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Hepatitis and Viral infection.

Code Identity

ICD-10-CM Code
B16.1
Billable Status
Yes — Valid for Submission
Code Describes
Acute hepatitis B with delta-agent without hepatic coma
Short Description
Acute hepatitis B with delta-agent without hepatic coma
Same as the full description in the CMS dataset.
Parent Code
B16
Acute hepatitis B

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB15-B19Viral hepatitis
CategoryB16Acute hepatitis B
This CodeB16.1Acute hepatitis B with delta-agent without hepatic coma

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute hepatitis B with hepatitis D
  • Acute type B viral hepatitis
  • Acute viral hepatitis
  • Viral hepatitis D

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
      • B
        • acute
          • with
            • delta-agent (coinfection) (without hepatic coma)
    • Hepatitis
      • D
    • Hepatitis
      • D
        • acute
    • Hepatitis
      • viral, virus
        • type
          • B
            • acute
              • with
                • delta-agent (coinfection) (without hepatic coma)
    • Hepatitis
      • viral, virus
        • type
          • D
    • Hepatitis
      • viral, virus
        • type
          • D
            • acute

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 B

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

Read the full article at MedlinePlus

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

Convert B16.1 to ICD-9-CMHistory

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

ICD-9-CM
070.31 Hpt B acte wo cm w dlta
Approximate The match is approximate rather than exact.

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 B16.1Overview

Is B16.1 (Acute hepatitis B) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute hepatitis B with delta-agent without hepatic coma on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does B16.1 group to?

When acute hepatitis B with delta-agent without hepatic coma 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 B16.1?

Under the General Equivalence Mappings, acute hepatitis B with delta-agent without hepatic coma converts to ICD-9-CM 070.31 (hpt B acte wo cm w dlta). The mapping is approximate, so confirm the match fits the documentation.

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.