2021 ICD-10-CM Code K31.1

Adult hypertrophic pyloric stenosis

Version 2021
Billable Code
Adult Diagnoses
MS-DRG Mapping

Valid for Submission

K31.1 is a billable diagnosis code used to specify a medical diagnosis of adult hypertrophic pyloric stenosis. The code K31.1 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

The ICD-10-CM code K31.1 might also be used to specify conditions or terms like acquired hypertrophic pyloric stenosis, acquired nonhypertrophic constriction of pylorus, acquired obstruction of pylorus, acquired obstruction of pylorus, acquired pyloric constriction , acquired pyloric stricture, etc.

The code K31.1 is applicable to adult patients aged 15 through 124 years inclusive. It is clinically and virtually impossible to use this code on a patient outside the stated age range.

ICD-10:K31.1
Short Description:Adult hypertrophic pyloric stenosis
Long Description:Adult hypertrophic pyloric stenosis

Code Classification

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code K31.1:


Inclusion Terms

Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.

Type 1 Excludes

Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code K31.1 are found in the index:

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10 Code Edits are applicable to this code:

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Convert K31.1 to ICD-9 Code

Information for Patients


Stomach Disorders

Also called: Gastric disorders

Your stomach is an organ between your esophagus and small intestine. It is where digestion of protein begins. The stomach has three tasks. It stores swallowed food. It mixes the food with stomach acids. Then it sends the mixture on to the small intestine.

Most people have a problem with their stomach at one time or another. Indigestion and heartburn are common problems. You can relieve some stomach problems with over-the-counter medicines and lifestyle changes, such as avoiding fatty foods or eating more slowly. Other problems like peptic ulcers or GERD require medical attention.

You should see a doctor if you have any of the following:

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


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Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)