2027 ICD-10-CM Diagnosis Code A48.0Gas gangrene

ICD-10-CM Codes›A00–B99›A30-A49›A48

ICD-10-CM A48.0
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A48.0 is a billable ICD-10-CM diagnosis code for gas gangrene. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 791, 793, 867 through 869. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 5 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections.

For Medicare Advantage risk adjustment, A48.0 maps to CMS-HCC Category 263 (Atherosclerosis of Arteries of the Extremities with Ulceration or Gangrene) under the V28 model, adding a risk factor of about 1.118 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
A48.0
Billable Status
Yes — Valid for Submission
Code Describes
Gas gangrene
Short Description
Gas gangrene
Same as the full description in the CMS dataset.
Parent Code
A48
Other bacterial diseases, not elsewhere classified

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA30-A49Other bacterial diseases
CategoryA48Other bacterial diseases, not elsewhere classified
This CodeA48.0Gas gangrene

Medicare Risk Adjustment (HCC)Billing

A48.0 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 263— Atherosclerosis of Arteries of the Extremities with Ulceration or Gangrene
Payment HCC · PY 2027 one of 127 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+1.118
community, non-dual, aged · ranges 0.696–1.432 across segments
Hierarchy
Supersedes HCC 264, HCC 383, and HCC 409
less severe related categories are not paid alongside HCC 263
Prior Model (CMS-HCC V24)
HCC 106
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 106 · ESRD (V21): HCC 106 · ESRD (V24): HCC 106
ESRD V21 weights: 0.321 dialysis, 0.754–1.385 functioning graft · ESRD V24 weights: 0.358 dialysis, 0.873–1.740 functioning graft
Part D (RxHCC)
Not mapped
A48.0 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Anaerobic cellulitis
  • Anaerobic myonecrosis
  • Gas gangrene
  • Gas gangrene caused by Clostridium edematiens
  • Gas gangrene caused by clostridium histolyticum
  • Gas gangrene caused by clostridium perfringens
  • Gas gangrene caused by clostridium septicum
  • Gas gangrene caused by Paeniclostridium sordellii
  • Gas gangrene of back
  • Gas gangrene of foot
  • Gas gangrene of forearm
  • Gas gangrene of hand
  • Gas gangrene of limb
  • Gas gangrene of lower leg
  • Gas gangrene of lower limb
  • Gas gangrene of neck
  • Gas gangrene of pelvic region of trunk
  • Gas gangrene of shoulder region
  • Gas gangrene of skin
  • Gas gangrene of thigh
  • Gas gangrene of upper arm
  • Gas gangrene of upper limb
  • Infection caused by Clostridium botulinum
  • Infection caused by Clostridium novyi
  • Infection caused by Clostridium perfringens
  • Intestinal gas gangrene
  • Uterine gas gangrene

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A48.0: its own notes plus those printed at A48 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Clostridial cellulitis
  • Clostridial myonecrosis

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From A48 Other bacterial diseases, not elsewhere classified applies to 8 codes

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name A48.0, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming A48.0: they are not reported together with it, unless the two conditions are unrelated.

  • A41.4 Sepsis due to anaerobes
    gas gangrene (A48.0)
  • I96 Gangrene, not elsewhere classified
    gas gangrene (A48.0)

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

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

CCSR INF003
Bacterial infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Gas Gangrene

    a severe condition resulting from bacteria invading healthy muscle from adjacent traumatized muscle or soft tissue. the infection originates in a wound contaminated with bacteria of the genus clostridium. c. perfringens accounts for the majority of cases (over eighty percent), while c. noyvi, c. septicum, and c. histolyticum cause most of the other cases.

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 A48.0 to ICD-9-CMHistory

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

ICD-9-CM
040.0 Gas gangrene
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About A48.0Overview

What is the ICD-10 code for gas gangrene?

The ICD-10-CM code for gas gangrene is A48.0 (sometimes written as A480). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A48.0 (Other bacterial diseases, not elsewhere classified) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report gas gangrene on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does A48.0 group to?

When gas gangrene is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 867, 869, 868, with relative weights from 0.6784 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A48.0 a CC or MCC?

CMS lists A48.0 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 5 closely related codes in its exclusion list.

Can A48.0 be reported with B47.1?

Not as a rule. The Excludes1 note at A48, which applies to A48.0, lists "actinomycetoma (B47.1)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What HCC is A48.0?

A48.0 (gas gangrene) maps to CMS-HCC Category 263 (Atherosclerosis of Arteries of the Extremities with Ulceration or Gangrene), commonly written as HCC 263, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 106 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.

Does A48.0 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, A48.0 adds a risk adjustment factor of about 1.118 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.696 to 1.432 depending on the payment segment). HCC 263 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 263 category page.