When is ICD-10 code Q42 used?

Doctors, hospitals, and insurers may use ICD-10 code Q42 when recording congenital absence, atresia and stenosis of large intestine in a standardized format. This entry may also act as a broader category that points toward more specific child codes.

Does ICD-10 code Q42 confirm a diagnosis?

No. A code helps standardize documentation and claims, but it should not be read as a substitute for a clinician's full assessment.

ICD10

ICD-10 Code Q42: Congenital absence, atresia and stenosis of large intestine

Name: ICD-10 Code Q42: Congenital absence, atresia and stenosis of large intestine
Creator: HealthAssure Clinical Team
Published: 2026-05-21T06:29:42.735Z

Q42 is an ICD-10 diagnosis entry used to group records related to Congenital absence, atresia and stenosis of large intestine. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA0).

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA0).

When is it used?

May be used when a clinician documents congenital absence, atresia and stenosis of large intestine in a patient's medical record.
May appear in hospital records, claims, referrals, and clinical documentation.
This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

A code alone does not explain severity, treatment plan, or outcome.
A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter

17Congenital malformations, deformations, chromosomal abnormalities, and genetic disorders (Q00-QA0)

block

Q38-Q45Other congenital malformations of the digestive system

currentQ38-Q45

Official coding notes

Includes

congenital obstruction, occlusion and stricture of large intestine

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Sibling codes

Q38Other congenital malformations of tongue, mouth and pharynx Q39Congenital malformations of esophagus Q40Other congenital malformations of upper alimentary tract Q41Congenital absence, atresia and stenosis of small intestine Q43Other congenital malformations of intestine Q44Congenital malformations of gallbladder, bile ducts and liver Q45Other congenital malformations of digestive system

Coding guidelines

Compatibility

Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.

Legacy codes

Q42

Replacement codes

Q42.0 — Congenital absence, atresia and stenosis of rectum with fistulaQ42.1 — Congenital absence, atresia and stenosis of rectum without fistulaQ42.2 — Congenital absence, atresia and stenosis of anus with fistulaQ42.3 — Congenital absence, atresia and stenosis of anus without fistulaQ42.8 — Congenital absence, atresia and stenosis of other parts of large intestineQ42.9 — Congenital absence, atresia and stenosis of large intestine, part unspecified

Common synonyms

Congenital absence, atresia and stenosis of large intestine

Frequently asked questions

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.