2027 ICD-10-CM Diagnosis Code K27.5Chronic or unspecified peptic ulcer, site unspecified, with perforation

ICD-10-CM Codes›K00–K95›K20-K31›K27

ICD-10-CM K27.5
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

K27.5 is a billable ICD-10-CM diagnosis code for chronic or unspecified peptic ulcer, site unspecified, 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 76 closely related codes. Coders also document this condition as chronic peptic ulcer with perforation. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Gastroduodenal ulcer and Gastrointestinal and biliary perforation.

For Medicare Advantage risk adjustment, K27.5 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
K27.5
Billable Status
Yes — Valid for Submission
Code Describes
Chronic or unspecified peptic ulcer, site unspecified, with perforation
Short Description
Chronic or unsp peptic ulcer, site unsp, with perforation
Parent Code
Peptic ulcer, site unspecified

Code Classification

ChapterK00–K95Diseases of the digestive system
SectionK20-K31Diseases of esophagus, stomach and duodenum
CategoryK27Peptic ulcer, site unspecified
This CodeK27.5Chronic or unspecified peptic ulcer, site unspecified, with perforation

Medicare Risk Adjustment (HCC)Billing

K27.5 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Superseded by HCC 77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
K27.5 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 peptic ulcer with perforation
  • Chronic peptic ulcer with perforation AND obstruction
  • Chronic peptic ulcer with perforation but without obstruction
  • Peptic ulcer with perforation
  • Peptic ulcer with perforation AND obstruction
  • Peptic ulcer with perforation but without obstruction

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to K27.5: its own notes plus those printed at K27, 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 K27 Peptic ulcer, site unspecified applies to 9 codes
  • gastroduodenal ulcer NOS
  • peptic ulcer NOS

Excludes1

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

From K27 Peptic ulcer, site unspecified applies to 9 codes
  • peptic ulcer of newborn (P78.82)

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 K27 Peptic ulcer, site unspecified 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 K27.5, its category, or a range that includes it.

Excludes1 4

These codes carry an Excludes1 note naming K27.5: they are not reported together with it, unless the two conditions are unrelated.

  • K25 Gastric ulcer
    peptic ulcer NOS (K27.-) names K27.-, which includes this code
  • K26 Duodenal ulcer
    peptic ulcer NOS (K27.-) names K27.-, which includes this code
  • K63.3 Ulcer of intestine
    peptic ulcer, site unspecified (K27.-) names K27.-, which includes this code
  • K92.2 Gastrointestinal hemorrhage, unspecified
    peptic ulcer with hemorrhage (K25-K28) names K25-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

Clinical InformationClinical

  • Peptic Ulcer

    ulcer that occurs in the regions of the gastrointestinal tract which come into contact with gastric juice containing pepsin and gastric acid. it occurs when there are defects in the mucosa barrier. the common forms of peptic ulcers are associated with helicobacter pylori and the consumption of nonsteroidal anti-inflammatory drugs (nsaids).

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 K27.5 to ICD-9-CMHistory

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

ICD-9-CM
533.50 Chr peptic ulcer 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 K27.5Overview

Is K27.5 (Peptic ulcer, site unspecified) a billable code?

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

What MS-DRG does K27.5 group to?

When chronic or unspecified peptic ulcer, site unspecified, 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 K27.5 a CC or MCC?

CMS lists K27.5 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 76 closely related codes in its exclusion list.

Can K27.5 be reported with P78.82?

Not as a rule. The Excludes1 note at K27, which applies to K27.5, lists "peptic ulcer of newborn (P78.82)". 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).

Does K27.5 need an additional code?

When the condition applies, yes. The Use Additional Code note at K27, which applies to K27.5, reads: code to identify: alcohol abuse and dependence (F10.-). The additional code is reported after K27.5.

What HCC is K27.5?

K27.5 (chronic or unspecified peptic ulcer, site unspecified, 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 K27.5 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, K27.5 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.