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K55.05 ICD-10-CM Code: Acute (reversible) ischemia of intestine, part unspecified

Compare with another code for K55.05Check this code on a claim

Billing Status: NO. This is a non-billable ICD-10-CM code: report a more specific billable code beneath it.

Coding at a Glance

Tabular directives
1 Excludes1 · 1 Excludes2

Not billable · FY2027A non-billable heading in the tabular list: report a more specific code beneath it.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too, and is marked with where it comes from.

Excludes1from K55Not reported with this code unless documented as unrelated
  • necrotizing enterocolitis of newborn (P77.-)
Excludes2from K55Not included here; may be reported together
  • angioectasia (angiodysplasia) duodenum (K31.81-)

Where it sits Source: CMS/NCHS

Under:Chapter 11: Diseases of the Digestive SystemK55-K64 Other diseases of intestinesK55 Vascular disorders of intestineK55.0 Acute vascular disorders of intestine

Codes under K55.05 (3)

  • K55.051Focal (segmental) acute (reversible) ischemia of intestine, part unspecifiedBillable
  • K55.052Diffuse acute (reversible) ischemia of intestine, part unspecifiedBillable
  • K55.059Acute (reversible) ischemia of intestine, part and extent unspecifiedBillable

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for K55.05 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on K55.05 itself; “inherited from” names the category or block whose note applies here.

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from K55

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

Source: inherited from K55

Coder workflow for K55.05

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

Before you code K55.05

  1. K55.05 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).

    ReviewK55.051, K55.052, K55.059

    See the relationships section · Guide: How to choose an ICD-10-CM code →

  2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with the code beneath K55.05. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support one of the more specific codes beneath K55.05?
    Yes → Select that code and continue the checks below on its own page.
    No → K55.05 cannot be reported as written. Where the codes beneath it include an unspecified code, that code applies when the record goes no further; otherwise query for the missing detail.

    ReviewK55.051, K55.052, K55.059

  2. Does the documentation support a condition named in K55.05’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewP77

Report the code beneath K55.05 that the documentation supports, not K55.05 itself. Then confirm that code is valid for the date of service on its own page.

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).
Acuity
Acute or chronic as documented; when both are documented and separate codes exist, both are reported with the acute code first (Guidelines I.B.8).
Any detail beyond this code’s title
What the record states that a more specific code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

  • Excludes1 — check before selecting K55.05(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with K55.05: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareP77

    See the official tabular notes · Guidelines I.A.12.a

  • Excludes2 — not part of K55.05(1 note)

    Coding workflow: The conditions named in this note are not included in K55.05. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareK31.81

    See the official tabular notes · Guidelines I.A.12.b

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: The provider documents the condition in the terms of this code’s title and records no further detail.

Coding question: Is a more specific sibling code supportable?

Path: Review the specific siblings in this subcategory and what each requires the record to state.

Reason: A more specific code needs documentation of the distinguishing element; without it the unspecified code is appropriate, and a provider query is the route to specificity (Guidelines I.A.9.b, I.B.18).

ReviewK55.01, K55.02, K55.03, K55.04

Documentation: Both the condition K55.05 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewP77

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.

Don’t confuse K55.05 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of K55.05 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

  • P77— Excludes1 conflict (Excludes1 — generally not reported together)

    Not coded here — the tabular list excludes this pair for the same encounter.

    Not reported together with this code, except where the two conditions are documented as unrelated.

    What moves you there: Documentation of necrotizing enterocolitis of newborn moves the case to P77; the two are not reported together unless documented as unrelated.

    Full comparison: K55.05 vs P77 →

  • K31.81— Excludes2 relationship (Informational)

    Distinct conditions — both may be reported.

    A distinct condition — both may be reported when both are documented.

    What moves you there: Documentation of angioectasia (angiodysplasia) duodenum adds K31.81; it is not part of this code and both may be reported when both are documented.

    Full comparison: K55.05 vs K31.81 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Acute (reversible) ischemia of intestine, part unspecified is a non-billable ICD-10-CM category code (K55.05). A more specific billable subcode must be selected for claims submission.

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

Verify Before Coding

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-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name K55.05 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 Excludes2 notes: I74 — Arterial embolism and thrombosis (via K55.0.-), I82 — Other venous embolism and thrombosis (via K55.0.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Related Codes

Same Index main term, other category

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

I82.890 — Acute embolism and thrombosis of other specified veins (specified site NEC), I82.891 — Chronic embolism and thrombosis of other specified veins (specified site NEC, chronic), I82.90 — Acute embolism and thrombosis of unspecified vein, I82.91 — Chronic embolism and thrombosis of unspecified vein (chronic), I82.A1 — Acute embolism and thrombosis of axillary vein (vein, axillary), I82.A2 — Chronic embolism and thrombosis of axillary vein (vein, axillary, chronic), I82.B1 — Acute embolism and thrombosis of subclavian vein (vein, subclavian), I82.B2 — Chronic embolism and thrombosis of subclavian vein (vein, subclavian, chronic), I82.C1 — Acute embolism and thrombosis of internal jugular vein (vein, internal jugular), I82.C2 — Chronic embolism and thrombosis of internal jugular vein (vein, internal jugular, chronic), K64.5 — Perianal venous thrombosis (anal), N28.0 — Ischemia and infarction of kidney (renal), N48.81 — Thrombosis of superficial vein of penis (penis, superficial vein), N48.89 — Other specified disorders of penis (corpus cavernosum), N50.1 — Vascular disorders of male genital organs (testis), N94.89 — Other specified conditions associated with female genital organs and menstrual cycle (genital organ, female NEC), O69.5 — Labor and delivery complicated by vascular lesion of cord (umbilical cord, complicating delivery), O87.0 — Superficial thrombophlebitis in the puerperium (puerperal, postpartum), O87.3 — Cerebral venous thrombosis in the puerperium (cerebrovenous sinus, puerperium), O99.43 — Diseases of the circulatory system complicating the puerperium (brain, puerperal), +74 more

Contextual Map

Every relationship of K55.05 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 K55.05 with these 2 related codes in Claim Check

Hierarchy

Referenced by Excludes2 notes

Nearest codes (36)

Change history

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Common coding questions

MedCoder editorial

Can K55.05 be billed directly?

No. K55.05 (Acute (reversible) ischemia of intestine, part unspecified) is a non-billable ICD-10-CM category code. A more specific billable subcode must be selected based on clinical documentation.

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 FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 2026) 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-derived 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 editorial 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.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

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. "K55.05 — Acute (reversible) ischemia of intestine, part unspecified." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/k55.05-acute-reversible-ischemia-of-intestine-part-unspecified

Change history

  • FY2017 — October 1, 2016
    Added to the code set
    Acute (reversible) ischemia of intestine, part unspecified
    FY2017 changes

Nearest Codes in This Family

Official ICD-10-CM classifications closest to K55.05 in its code family, with their registry titles.

View all codes in the K55 family