2026 ICD-10-CM Diagnosis Code Q43.6Congenital fistula of rectum and anus

ICD-10-CM Codes›Q00-Q99›Q38-Q45›Q43

ICD-10-CM Q43.6
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

Q43.6 is a billable ICD-10-CM diagnosis code for congenital fistula of rectum and anus. 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. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Digestive congenital anomalies.

Code Identity

ICD-10-CM Code
Q43.6
Billable Status
Yes — Valid for Submission
Code Describes
Congenital fistula of rectum and anus
Short Description
Congenital fistula of rectum and anus
Same as the full description in the CMS dataset.
Parent Code
Q43
Other congenital malformations of intestine

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ38-Q45Other congenital malformations of the digestive system
CategoryQ43Other congenital malformations of intestine
This CodeQ43.6Congenital fistula of rectum and anus

Present on Admission (POA)Billing

Q43.6 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Anorectal fistula
  • Congenital anoperineal fistula
  • Congenital anorectal fistula due to high anorectal malformation
  • Congenital anorectal fistula due to intermediate anorectal malformation
  • Congenital anorectal fistula due to low anorectal malformation
  • Congenital fecal fistula
  • Congenital fistula of anus
  • Congenital fistula of rectum
  • Congenital fistula of rectum and anus
  • Enterocutaneous fistula

Tabular List NotesGuidance

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

Type 1 Excludes

  • congenital fistula of anus with absence, atresia and stenosis Q42.2
  • congenital fistula of rectum with absence, atresia and stenosis Q42.0
  • congenital rectovaginal fistula Q52.2
  • congenital urethrorectal fistula Q64.73
  • pilonidal fistula or sinus L05

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.

    • Fistula(cutaneous)
      • anus, anal (recurrent) (infectional)
        • congenital
    • Fistula(cutaneous)
      • fecal
        • congenital
    • Fistula(cutaneous)
      • rectum (to skin)
        • congenital

Clinical ClassificationClinical

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

CCSR MAL002
Digestive congenital anomalies
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Anal Disorders

Your anus is the opening at the end of your large intestine. It is where stool (poop) leaves your body.

The full article covers:

  • What is the anus?
  • What are anal disorders?
  • What are the symptoms of anal disorders?
  • How are anal disorders diagnosed?
  • How are anal disorders treated?

Read the full article at MedlinePlus

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

Convert Q43.6 to ICD-9-CMHistory

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

ICD-9-CM
751.5 Intestinal anomaly NEC
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 Q43.6Overview

Is Q43.6 (Other congenital malformations of intestine) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report congenital fistula of rectum and anus on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does Q43.6 group to?

When congenital fistula of rectum and anus 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.

Is Q43.6 exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for congenital fistula of rectum and anus on inpatient claims.

What is the ICD-9 equivalent of Q43.6?

Under the General Equivalence Mappings, congenital fistula of rectum and anus converts to ICD-9-CM 751.5 (intestinal anomaly NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.