2026 ICD-10-CM Diagnosis Code K42.1Umbilical hernia with gangrene

ICD-10-CM Codes›K00–K95›K40-K46›K42

ICD-10-CM K42.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

K42.1 is a billable ICD-10-CM diagnosis code for umbilical hernia with gangrene. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 393 through 395. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abdominal hernia and Gangrene.

Code Identity

ICD-10-CM Code
K42.1
Billable Status
Yes — Valid for Submission
Code Describes
Umbilical hernia with gangrene
Short Description
Umbilical hernia with gangrene
Same as the full description in the CMS dataset.
Parent Code
K42
Umbilical hernia

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK40-K46Hernia
CategoryK42Umbilical hernia
This CodeK42.1Umbilical hernia with gangrene

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Congenital omphalocele
  • Congenital umbilical hernia
  • Gangrene due to recurrent umbilical hernia
  • Obstructed umbilical hernia
  • Omphalocele with gangrene
  • Paraumbilical hernia
  • Paraumbilical hernia with gangrene
  • Paraumbilical hernia with gangrene AND obstruction
  • Paraumbilical hernia with obstruction
  • Umbilical hernia with gangrene
  • Umbilical hernia with gangrene AND obstruction

Tabular List NotesGuidance

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

Inclusion Terms

  • Gangrenous umbilical hernia

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.

    • Hernia, hernial(acquired) (recurrent)
      • umbilicus, umbilical
        • with
          • gangrene (and obstruction)
    • Incarceration, incarcerated
      • exomphalos
        • gangrenous
    • Incarceration, incarcerated
      • sarcoepiplomphalocele
        • with gangrene

Clinical ClassificationClinical

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

CCSR DIG010
Abdominal hernia
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR CIR028
Gangrene
Default principal diagnosis: inpatient No · outpatient No

Clinical InformationClinical

  • Gangrenous Umbilical Hernia

    a protrusion of necrotic tissue through the abdominal wall under the skin near the umbilicus.

  • Umbilical Hernia

    protrusion of the abdominal cavity contents through the abdominal wall at the umbilicus.

  • Umbilical Hernia with Obstruction without Mention of Gangrene

    the protrusion of contents of the abdominal cavity through the abdominal wall, at the site of the umbilicus, which results in obstruction, without mention of necrosis of the herniated contents.

  • Umbilical Hernia without Mention of Obstruction or Gangrene

    the protrusion of contents of the abdominal cavity through the abdominal wall, at the site of the umbilicus, without mention of obstruction or necrosis of the herniated contents.

Patient EducationClinical

Gangrene

Gangrene is the death of tissues in your body. It happens when a part of your body loses its blood supply. Gangrene can happen on the surface of the body, such as on the skin, or inside the body, in muscles or organs. Causes include:

Read the full article at MedlinePlus

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

Convert K42.1 to ICD-9-CMHistory

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

ICD-9-CM
551.1 Umbilical hernia w gangr
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 K42.1Overview

Is K42.1 (Umbilical hernia) a billable code?

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

What MS-DRG does K42.1 group to?

When umbilical hernia with gangrene is the principal diagnosis on an inpatient stay, it groups to MS-DRG 393, 394, 395, with relative weights from 0.6490 to 1.5993 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of K42.1?

Under the General Equivalence Mappings, umbilical hernia with gangrene converts to ICD-9-CM 551.1 (umbilical hernia w gangr). 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.