2026 ICD-10-CM Diagnosis Code I32Pericarditis in diseases classified elsewhere

ICD-10-CM CodesI00–I99I30-I5AI32

ICD-10-CM I32
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I32 is a billable ICD-10-CM diagnosis code for pericarditis in diseases classified elsewhere. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 314 through 316. The code is a manifestation code that cannot be reported as the principal diagnosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Pericarditis and pericardial disease.

Code Identity

ICD-10-CM Code
I32
Billable Status
Yes — Valid for Submission
Code Describes
Pericarditis in diseases classified elsewhere
Chapter
I30-I5A
Other forms of heart disease

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI30-I5AOther forms of heart disease
CategoryI32Pericarditis in diseases classified elsewhere
This CodeI32Pericarditis in diseases classified elsewhere

Code EditsBilling

Medicare Code Editor checks that affect claim validity for I32.

Manifestation codes describe the manifestation of an underlying disease, not the disease itself, and therefore should not be used as a principal diagnosis.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute pericarditis secondary to uremia
  • African histoplasmosis
  • Chronic pericarditis
  • Histoplasma capsulatum with pericarditis
  • Histoplasma duboisii with pericarditis
  • Histoplasmosis with pericarditis
  • Pericarditis associated with atrial septal defect
  • Pericarditis associated with severe chronic anemia
  • Pericarditis due to familial Mediterranean fever
  • Pericarditis due to infectious mononucleosis
  • Pericarditis secondary to aortic aneurysm
  • Pericarditis secondary to myxedema
  • Pericarditis secondary to non-penetrating trauma
  • Pericarditis secondary to uremia
  • Post-cardiac injury syndrome
  • Post-traumatic pericarditis

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Code First

  • underlying disease

Type 1 Excludes

Clinical ClassificationClinical

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

CCSR CIR006
Pericarditis and pericardial disease
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Pericardial Disorders

The pericardium is a membrane, or sac, that surrounds your heart. It holds the heart in place and helps it work properly. Problems with the pericardium include:

Read the full article at MedlinePlus

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

Convert I32 to ICD-9-CMHistory

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

ICD-9-CM
420.0 Ac pericardit in oth dis
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About I32Overview

Is I32 (Pericarditis in diseases classified elsewhere) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report pericarditis in diseases classified elsewhere on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does I32 group to?

On inpatient claims, pericarditis in diseases classified elsewhere maps to MS-DRG 314, 315, 316, with relative weights from 0.6821 to 2.0852 depending on complications. Higher weights mean higher Medicare reimbursement.

Can I32 be a principal diagnosis?

No. This is a manifestation code: pericarditis in diseases classified elsewhere describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.

What is the ICD-9 equivalent of I32?

Under the General Equivalence Mappings, pericarditis in diseases classified elsewhere converts to ICD-9-CM 420.0 (ac pericardit in oth dis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.