Skip to main content

Q40.2 ICD-10-CM Code: Other specified congenital malformations of stomach

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
6 inclusion terms

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43, Appendix B.

  • MS-DRG 393 — OTHER DIGESTIVE SYSTEM DIAGNOSES WITH MCC (MDC 06)
  • MS-DRG 394 — OTHER DIGESTIVE SYSTEM DIAGNOSES WITH CC (MDC 06)
  • MS-DRG 395 — OTHER DIGESTIVE SYSTEM DIAGNOSES WITHOUT CC/MCC (MDC 06)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for Q40.2 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Congenital displacement of stomach
  • Congenital diverticulum of stomach
  • Congenital hourglass stomach
  • Congenital duplication of stomach
  • Megalogastria
  • Microgastria

Coder workflow for Q40.2

MedCoder structured workflow — derived from this code’s own official record

Before you code Q40.2

  1. “Other” (NEC) means the condition is specified in the record but no dedicated code captures it. Confirm the documented form is not one a sibling code names before settling on Q40.2; if the record states no specifics at all, the unspecified sibling applies instead. “Other” codes are for documented conditions the classification gives no specific code; “unspecified” codes are for records lacking the detail (Guidelines I.A.9.a, I.A.9.b).

    ReviewQ40.0, Q40.1

    See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Any detail beyond this code’s title
What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Code Overview

Other specified congenital malformations of stomach is a billable ICD-10-CM diagnosis code (Q40.2).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Indexed Clinical Terms (22)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Verify Before Coding

  • No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name Q40.2 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 2 Excludes1 notes: K31.2 — Hourglass stricture and stenosis of stomach, K31.4 — Gastric diverticulum.

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 3 MS-DRGs: DRG 393 (MDC 06), DRG 394 (MDC 06), DRG 395 (MDC 06).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):MAL002 — Digestive congenital anomalies (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Digestive congenital anomalies).

Q39.1 — Atresia of esophagus with tracheo-esophageal fistula, Q39.2 — Congenital tracheo-esophageal fistula without atresia, Q39.3 — Congenital stenosis and stricture of esophagus, Q39.4 — Esophageal web, Q39.5 — Congenital dilatation of esophagus, Q39.6 — Congenital diverticulum of esophagus, Q39.8 — Other congenital malformations of esophagus, Q39.9 — Congenital malformation of esophagus, unspecified, Q40.0 — Congenital hypertrophic pyloric stenosis, Q40.1 — Congenital hiatus hernia, Q40.3 — Congenital malformation of stomach, unspecified, Q40.8 — Other specified congenital malformations of upper alimentary tract, Q40.9 — Congenital malformation of upper alimentary tract, unspecified, Q41.0 — Congenital absence, atresia and stenosis of duodenum, Q41.1 — Congenital absence, atresia and stenosis of jejunum, Q41.2 — Congenital absence, atresia and stenosis of ileum, Q41.8 — Congenital absence, atresia and stenosis of other specified parts of small intestine, Q41.9 — Congenital absence, atresia and stenosis of small intestine, part unspecified, Q42.0 — Congenital absence, atresia and stenosis of rectum with fistula, Q42.1 — Congenital absence, atresia and stenosis of rectum without fistula, +41 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main terms “Agenesis”, “Absence”, “Anomaly, anomalous”, …; these codes share that main term but sit in a different category of the Tabular List.

Q38.5 — Congenital malformations of palate, not elsewhere classified (uvula), Q38.6 — Other congenital malformations of mouth (lip), Q38.7 — Congenital pharyngeal pouch (pharynx), Q38.8 — Other congenital malformations of pharynx (throat), Q39.1 — Atresia of esophagus with tracheo-esophageal fistula (esophagus, congenital, with atresia of esophagus), Q39.2 — Congenital tracheo-esophageal fistula without atresia (esophagus, congenital), Q39.3 — Congenital stenosis and stricture of esophagus (cardia, congenital), Q39.6 — Congenital diverticulum of esophagus (esophagus), Q39.8 — Other congenital malformations of esophagus (esophagus), Q39.9 — Congenital malformation of esophagus, unspecified (esophagus), Q41.0 — Congenital absence, atresia and stenosis of duodenum (duodenum), Q41.1 — Congenital absence, atresia and stenosis of jejunum (jejunum), Q41.2 — Congenital absence, atresia and stenosis of ileum (ileum), Q41.8 — Congenital absence, atresia and stenosis of other specified parts of small intestine (intestine, congenital, specified NEC), Q41.9 — Congenital absence, atresia and stenosis of small intestine, part unspecified (intestine), Q42.0 — Congenital absence, atresia and stenosis of rectum with fistula (rectum, with fistula), Q42.1 — Congenital absence, atresia and stenosis of rectum without fistula (rectum), Q42.2 — Congenital absence, atresia and stenosis of anus with fistula (anus, with fistula), Q42.3 — Congenital absence, atresia and stenosis of anus without fistula (anus), Q42.8 — Congenital absence, atresia and stenosis of other parts of large intestine (cecum), +894 more

Contextual Map

Every relationship of Q40.2 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run Q40.2 with these 2 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

  • MDC 06 — Diseases and Disorders of the Digestive System[MDC crossing]: “Diseases and Disorders of the Digestive System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 5,744 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries (22)

  • Absence (of) (organ or part) (complete or partial), stomach (acquired) (partial), congenital[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Agenesis, gastric[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Agenesis, stomach[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Anomaly, anomalous (congenital) (unspecified type), cascade stomach[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Anomaly, anomalous (congenital) (unspecified type), hourglass stomach[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Contraction, contracture, contracted (s), hourglass, stomach, congenital[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Contraction, contracture, contracted (s), stomach, hourglass, congenital[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Displacement, displaced, gastric mucosa (congenital)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • and 14 more

Nearest codes

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder structured relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "Q40.2 — Other specified congenital malformations of stomach." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/q40.2-other-specified-congenital-malformations-of-stomach

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Other specified congenital malformations of stomach

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to Q40.2 in its code family, with their registry titles.

View all codes in the Q40 family