2027 ICD-10-CM Diagnosis Code K28.5Chronic or unspecified gastrojejunal ulcer with perforation

ICD-10-CM Codes›K00–K95›K20-K31›K28

ICD-10-CM K28.5
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

K28.5 is a billable ICD-10-CM diagnosis code for chronic or unspecified gastrojejunal ulcer with perforation. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 380 through 382. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 75 closely related codes. Coders also document this condition as chronic gastrojejunal ulcer with obstruction. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Gastroduodenal ulcer and Gastrointestinal and biliary perforation.

For Medicare Advantage risk adjustment, K28.5 maps to CMS-HCC Category 78 (Intestinal Obstruction/Perforation) under the V28 model, adding a risk factor of about 0.326 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
K28.5
Billable Status
Yes — Valid for Submission
Code Describes
Chronic or unspecified gastrojejunal ulcer with perforation
Short Description
Chronic or unspecified gastrojejunal ulcer with perforation
Same as the full description in the CMS dataset.
Parent Code
Gastrojejunal ulcer

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK20-K31Diseases of esophagus, stomach and duodenum
CategoryK28Gastrojejunal ulcer
This CodeK28.5Chronic or unspecified gastrojejunal ulcer with perforation

Medicare Risk Adjustment (HCC)Billing

K28.5 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 78— Intestinal Obstruction/Perforation
Payment HCC · PY 2027 one of 76 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.326
community, non-dual, aged · ranges 0.326–0.688 across segments
Hierarchy
Superseded by HCC 77
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 33
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 33 · ESRD (V21): HCC 33 · ESRD (V24): HCC 33
ESRD V21 weights: 0.072 dialysis, 0.285–0.346 functioning graft · ESRD V24 weights: 0.078 dialysis, 0.250–0.474 functioning graft
Part D (RxHCC)
Not mapped
K28.5 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Chronic gastrojejunal ulcer with obstruction
  • Chronic gastrojejunal ulcer with perforation
  • Chronic gastrojejunal ulcer with perforation AND with obstruction
  • Chronic gastrojejunal ulcer with perforation but without obstruction
  • Gastrojejunal ulcer with perforation
  • Gastrojejunal ulcer with perforation AND obstruction
  • Gastrojejunal ulcer with perforation but without obstruction

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to K28.5: its own notes plus those printed at K28, block K20-K31, and Chapter 11. 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 K28 Gastrojejunal ulcer applies to 9 codes
  • anastomotic ulcer (peptic) or erosion
  • gastrocolic ulcer (peptic) or erosion
  • gastrointestinal ulcer (peptic) or erosion
  • gastrojejunal ulcer (peptic) or erosion
  • jejunal ulcer (peptic) or erosion
  • marginal ulcer (peptic) or erosion
  • stomal ulcer (peptic) or erosion

Excludes1

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

From K28 Gastrojejunal ulcer applies to 9 codes
  • primary ulcer of small intestine (K63.3)

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 Block K20-K31 Diseases of esophagus, stomach and duodenum applies to 106 codes
From Chapter 11 (K00-K95) Diseases of the digestive system applies to 863 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From K28 Gastrojejunal ulcer applies to 9 codes
  • code to identify:
  • alcohol abuse and dependence (F10.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name K28.5, its category, or a range that includes it.

Excludes1 4

These codes carry an Excludes1 note naming K28.5: they are not reported together with it, unless the two conditions are unrelated.

  • K63.3 Ulcer of intestine
    gastrointestinal ulcer (K28.-) names K28.-, which includes this code
  • K63.3 Ulcer of intestine
    gastrojejunal ulcer (K28.-) names K28.-, which includes this code
  • K63.3 Ulcer of intestine
    jejunal ulcer (K28.-) names K28.-, which includes this code
  • K92.2 Gastrointestinal hemorrhage, unspecified
    peptic ulcer with hemorrhage (K25-K28) names K25-K28, which includes this code

Excludes2 1

These codes carry an Excludes2 note naming K28.5: its condition is not part of those codes, and both may be reported when the patient has both.

  • K91 Intraoperative and postprocedural complications and disorders of digestive system, not elsewhere classified
    gastrojejunal ulcer (K28.-) names K28.-, which includes this code

Index to Diseases and InjuriesGuidance

Clinical ClassificationClinical

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

CCSR DIG005
Gastroduodenal ulcer
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR DIG006
Gastrointestinal and biliary perforation
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Peptic Ulcer

A peptic ulcer is a sore in the lining of your stomach or your duodenum, the first part of your small intestine. A burning stomach pain is the most common symptom. The pain:

Read the full article at MedlinePlus

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

Convert K28.5 to ICD-9-CMHistory

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

ICD-9-CM
534.50 Chr marginal ulc w perf
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About K28.5Overview

What is the ICD-10 code for chronic or unspecified gastrojejunal ulcer with perforation?

The ICD-10-CM code for chronic or unspecified gastrojejunal ulcer with perforation is K28.5 (sometimes written as K285). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is K28.5 (Gastrojejunal ulcer) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report chronic or unspecified gastrojejunal ulcer with perforation on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does K28.5 group to?

When chronic or unspecified gastrojejunal ulcer with perforation is the principal diagnosis on an inpatient stay, it groups to MS-DRG 381, 380, 382, with relative weights from 0.7283 to 1.9243 depending on complications. Higher weights mean higher Medicare reimbursement.

Is K28.5 a CC or MCC?

CMS lists K28.5 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 75 closely related codes in its exclusion list.

Can K28.5 be reported with K63.3?

Not as a rule. The Excludes1 note at K28, which applies to K28.5, lists "primary ulcer of small intestine (K63.3)". 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).

What HCC is K28.5?

K28.5 (chronic or unspecified gastrojejunal ulcer with perforation) maps to CMS-HCC Category 78 (Intestinal Obstruction/Perforation), commonly written as HCC 78, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 33 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.

Does K28.5 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, K28.5 adds a risk adjustment factor of about 0.326 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.326 to 0.688 depending on the payment segment). A more severe related category (HCC 77) supersedes it when both are reported. See the full factor table on the HCC 78 category page.