2027 ICD-10-CM Diagnosis Code A04.71Enterocolitis due to Clostridium difficile, recurrent

ICD-10-CM Codes›A00–B99›A00-A09›A04

ICD-10-CM A04.71
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A04.71 is a billable ICD-10-CM diagnosis code for enterocolitis due to Clostridium difficile, recurrent. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 371 through 373. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 225 closely related codes. Coders also document this condition as clostridioides difficile infection. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections and Intestinal infection.

Code Identity

ICD-10-CM Code
A04.71
Billable Status
Yes — Valid for Submission
Code Describes
Enterocolitis due to Clostridium difficile, recurrent
Short Description
Enterocolitis due to Clostridium difficile, recurrent
Same as the full description in the CMS dataset.
Parent Code
A04.7
Enterocolitis due to Clostridium difficile

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA00-A09Intestinal infectious diseases
CategoryA04Other bacterial intestinal infections
This CodeA04.71Enterocolitis due to Clostridium difficile, recurrent

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Clostridioides difficile infection
  • Clostridium difficile colitis
  • Clostridium difficile diarrhea
  • Intestinal infection caused by Clostridioides difficile
  • Recurrent Clostridium difficile infection
  • Recurrent colitis caused by Clostridium difficile
  • Recurrent diarrhea caused by Clostridium difficile
  • Recurrent infection of gastrointestinal tract

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A04.71: its own notes plus those printed at A04 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

Excludes1

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

From A04 Other bacterial intestinal infections applies to 11 codes
  • bacterial foodborne intoxications, NEC (A05.-)
  • tuberculous enteritis (A18.32)

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 A04.71, its category, or a range that includes it.

Excludes1 3

These codes carry an Excludes1 note naming A04.71: they are not reported together with it, unless the two conditions are unrelated.

  • Z86.17 Personal history of Clostridioides difficile infection
    enterocolitis due to Clostridium difficile, recurrent (A04.71)
  • A05 Other bacterial foodborne intoxications, not elsewhere classified
    Clostridium difficile foodborne intoxication and infection (A04.7-) names A04.7-, which includes this code
  • K59.3 Megacolon, not elsewhere classified
    megacolon (due to) (in) Clostridium difficile (A04.7-) names A04.7-, which includes this code

Excludes2 3

These codes carry an Excludes2 note naming A04.71: its condition is not part of those codes, and both may be reported when the patient has both.

  • K55.3 Necrotizing enterocolitis
    necrotizing enterocolitis due to Clostridium difficile (A04.7-) names A04.7-, which includes this code
  • Block P35-P39 Infections specific to the perinatal period
    intestinal infectious disease (A00-A09) names A00-A09, which includes this code
  • P37 Other congenital infectious and parasitic diseases
    infectious neonatal diarrhea (A00-A09) names A00-A09, which includes this code

Code First 1

These codes say to code first a condition named in the note, and A04.71 is one of the conditions named.

  • M49 Spondylopathies in diseases classified elsewhere
    enterobacterial infections (A01-A04) names A01-A04, which includes this code

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 No · outpatient No
CCSR DIG001
Intestinal infection
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

C. diff Infections

C. diff is a bacterium that can cause diarrhea and more serious intestinal conditions such as colitis. You may see it called other names, such as Clostridioides difficile (the new name), Clostridium difficile (an older name), and C. difficile. It causes close to half a million illnesses each year.

The full article covers:

  • What is C. diff?
  • What causes C. diff infections?
  • Who is more likely to get a C. diff infection?
  • What are the symptoms of C. diff infections?
  • How are C. diff infections diagnosed?
  • What are the treatments for C. diff infections?
  • Can C. diff infections be prevented?

Read the full article at MedlinePlus

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

Convert A04.71 to ICD-9-CMHistory

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

ICD-9-CM
008.45 Int inf clstrdium dfcile
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement A04.71 replaces the following previously assigned code(s):

  • A04.7 - Enterocolitis due to Clostridium difficile
FY 2019AddedAdded to the ICD-10-CM code setEffective October 1, 2018.
FY 2020–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About A04.71Overview

What is the ICD-10 code for enterocolitis due to Clostridium difficile, recurrent?

The ICD-10-CM code for enterocolitis due to Clostridium difficile, recurrent is A04.71 (sometimes written as A0471). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A04.71 (Enterocolitis due to Clostridium difficile) a billable code?

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

What MS-DRG does A04.71 group to?

When enterocolitis due to Clostridium difficile, recurrent is the principal diagnosis on an inpatient stay, it groups to MS-DRG 372, 371, 373, with relative weights from 0.6945 to 1.7087 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A04.71 a CC or MCC?

CMS lists A04.71 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 225 closely related codes in its exclusion list.

Can A04.71 be reported with a code from A05?

Not as a rule. The Excludes1 note at A04, which applies to A04.71, lists "bacterial foodborne intoxications, NEC (A05.-)". 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).