I30.1 ICD-10-CM Code: Infective pericarditis

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for I30.1 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on I30.1 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for I30.1

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

Before you code I30.1

1. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with I30.1. 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 a condition named in I30.1’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.

   ReviewI24.1, I01.0, B33.23

Consider I30.1. Then work the Use Additional Code note, and confirm the code is valid for the date of service in the Verify section.

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).

The conditions the Use Additional Code note names

Reported with this code when documented; a conditional instruction (“if applicable”, “if known”) applies only when the record supports it.

Official instructions as workflow

• Excludes1 — check before selecting I30.1(3 notes)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with I30.1: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareI24.1, I01.0, B33.23

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

• Use Additional Code — after identifying I30.1(1 note)

  Coding workflow: Check whether the documentation supports the additional code(s) the note names, and report them with I30.1 when it does. Where the instruction is conditional (“if applicable”, “if known”), it applies only when the record documents the condition.

  See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

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

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.

Indexed Clinical Terms (14)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic), pericardial
• Pericarditis (with decompensation) (with effusion), bacterial (acute) (subacute) (with serous or seropurulent effusion)
• Pericarditis (with decompensation) (with effusion), fibrinopurulent
• Pericarditis (with decompensation) (with effusion), infective
• Pericarditis (with decompensation) (with effusion), pneumococcal
• Pericarditis (with decompensation) (with effusion), purulent
• Pericarditis (with decompensation) (with effusion), septic
• Pericarditis (with decompensation) (with effusion), staphylococcal
• Pericarditis (with decompensation) (with effusion), streptococcal
• Pericarditis (with decompensation) (with effusion), suppurative
• Pericarditis (with decompensation) (with effusion), viral
• Pneumopyopericardium
• Pyopericarditis, pyopericardium
• Pyopneumopericardium

Don’t confuse I30.1 with…

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

The codes most likely to be picked instead of I30.1 — 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.

• I24.1— 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 Dressler's syndrome moves the case to I24.1; the two are not reported together unless documented as unrelated.

  Full comparison: I30.1 vs I24.1 →

• I01.0— 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 rheumatic pericarditis (acute) moves the case to I01.0; the two are not reported together unless documented as unrelated.

  Full comparison: I30.1 vs I01.0 →

• B33.23— 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 viral pericarditis due to Coxsackie virus moves the case to B33.23; the two are not reported together unless documented as unrelated.

  Full comparison: I30.1 vs B33.23 →

• I30.9— Specificity relationship (Review)

  Overlapping diagnoses in the same category.

  Overlapping codes in the same category — the documentation decides which is the more specific fit.

  What moves you there: A record that documents no more than “Acute pericarditis, unspecified” takes I30.9; specificity in the record moves it back here.

  Full comparison: I30.1 vs I30.9 →

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.

Verify Before Coding

• CC as a secondary diagnosis (FY2026). Can raise the stay's MS-DRG severity tier.

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 structured relationships — computed from published CMS and AHRQ datasets

Other codes that name I30.1 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 1 Excludes1 note: I01.0 — Acute rheumatic pericarditis (via I30.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 16 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 3 MS-DRGs: DRG 314 (MDC 05), DRG 315 (MDC 05), DRG 316 (MDC 05).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):CIR006 — Pericarditis and pericardial disease (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

I01.0 — Acute rheumatic pericarditis, I09.2 — Chronic rheumatic pericarditis, I27.841 — Fontan-associated lymphatic dysfunction, I27.848 — Other Fontan-associated condition, I27.849 — Fontan related circulation, unspecified, I30.0 — Acute nonspecific idiopathic pericarditis, I30.8 — Other forms of acute pericarditis, I30.9 — Acute pericarditis, unspecified, I31.39 — Other pericardial effusion (noninflammatory), I31.8 — Other specified diseases of pericardium, I31.9 — Disease of pericardium, unspecified, I87.8 — Other specified disorders of veins, I87.9 — Disorder of vein, unspecified, I99.8 — Other disorder of circulatory system, I99.9 — Unspecified disorder of circulatory system

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Pericarditis and pericardial disease).

A39.53 — Meningococcal pericarditis, B33.23 — Viral pericarditis, I01.0 — Acute rheumatic pericarditis, I09.2 — Chronic rheumatic pericarditis, I30.0 — Acute nonspecific idiopathic pericarditis, I30.8 — Other forms of acute pericarditis, I30.9 — Acute pericarditis, unspecified, I31.0 — Chronic adhesive pericarditis, I31.1 — Chronic constrictive pericarditis, I31.2 — Hemopericardium, not elsewhere classified, I31.3 — Pericardial effusion (noninflammatory), I31.31 — Malignant pericardial effusion in diseases classified elsewhere, I31.39 — Other pericardial effusion (noninflammatory), I31.4 — Cardiac tamponade, I31.8 — Other specified diseases of pericardium, I31.9 — Disease of pericardium, unspecified, I32 — Pericarditis in diseases classified elsewhere, M32.12 — Pericarditis in systemic lupus erythematosus

Same Index main term, other category

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

G06.2 — Extradural and subdural abscess, unspecified (epidural), G09 — Sequelae of inflammatory diseases of central nervous system (cerebral, sequelae), H00.03 — Abscess of eyelid (eyelid), H16.31 — Corneal abscess (cornea), H27.8 — Other specified disorders of lens (lens), H60.0 — Abscess of external ear (ear, external), I01.0 — Acute rheumatic pericarditis (rheumatic), I02.0 — Rheumatic chorea with heart involvement (acute, with chorea), I09.2 — Chronic rheumatic pericarditis (chronic, rheumatic), I24.1 — Dressler's syndrome (postinfarction), I31.0 — Chronic adhesive pericarditis (fibrous), I31.1 — Chronic constrictive pericarditis (calcareous), I31.8 — Other specified diseases of pericardium (neoplastic), I31.9 — Disease of pericardium, unspecified, I40.0 — Infective myocarditis (myocardium), I77.2 — Rupture of artery (atheromatous), I77.89 — Other specified disorders of arteries and arterioles (artery), I88.0 — Nonspecific mesenteric lymphadenitis (lymph, lymphatic, gland or node, mesentery), J32.0 — Chronic maxillary sinusitis (maxilla, maxillary, sinus), J32.1 — Chronic frontal sinusitis (frontal sinus), +174 more

Contextual Map

Every relationship of I30.1 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 I30.1 with these 4 related codes in Claim Check

Hierarchy

• I00-I99 — Chapter 9: Diseases of the Circulatory System (I00-I99) (I00-I99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I30-I5A — Other forms of heart disease[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Use Additional Code

• B95 — Streptococcus, Staphylococcus, and Enterococcus as the cause of diseases classified elsewhere[Use Additional Code]: “code (B95-B97) to identify infectious agent”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• B96 — Other bacterial agents as the cause of diseases classified elsewhere[Use Additional Code]: “code (B95-B97) to identify infectious agent”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• B97 — Viral agents as the cause of diseases classified elsewhere[Use Additional Code]: “code (B95-B97) to identify infectious agent”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Excludes1 notes

• I01.0 — Acute rheumatic pericarditis[Excludes1](via I30.-): “acute pericarditis not specified as rheumatic (I30.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• CIR006 — Pericarditis and pericardial disease[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

MS-DRG Grouper

• CC — Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (CC).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2026
• DRG 314 — OTHER CIRCULATORY SYSTEM DIAGNOSES WITH MCC[MS-DRG]: “OTHER CIRCULATORY SYSTEM DIAGNOSES WITH MCC (MDC 05)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 315 — OTHER CIRCULATORY SYSTEM DIAGNOSES WITH CC[MS-DRG]: “OTHER CIRCULATORY SYSTEM DIAGNOSES WITH CC (MDC 05)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 316 — OTHER CIRCULATORY SYSTEM DIAGNOSES WITHOUT CC/MCC[MS-DRG]: “OTHER CIRCULATORY SYSTEM DIAGNOSES WITHOUT CC/MCC (MDC 05)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

• MDC 05 — Diseases and Disorders of the Circulatory System[MDC crossing]: “Diseases and Disorders of the Circulatory System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 17,209 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries (14)

• Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic), pericardial[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pericarditis (with decompensation) (with effusion), bacterial (acute) (subacute) (with serous or seropurulent effusion)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pericarditis (with decompensation) (with effusion), fibrinopurulent[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pericarditis (with decompensation) (with effusion), infective[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pericarditis (with decompensation) (with effusion), pneumococcal[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pericarditis (with decompensation) (with effusion), purulent[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pericarditis (with decompensation) (with effusion), septic[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pericarditis (with decompensation) (with effusion), staphylococcal[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• and 6 more

Nearest codes

• I30 — Acute pericarditis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I30.0 — Acute nonspecific idiopathic pericarditis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I30.8 — Other forms of acute pericarditis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I30.9 — Acute pericarditis, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Change history

• FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

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 FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page

Claim edits Official source data

CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page

Inpatient payment groups Official source data

CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 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 structured 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 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.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Nearest Codes in This Family

Official ICD-10-CM classifications closest to I30.1 in its code family, with their registry titles.

• I30 — Acute pericarditis
• I30.0 — Acute nonspecific idiopathic pericarditis
• I30.8 — Other forms of acute pericarditis
• I30.9 — Acute pericarditis, unspecified

View all codes in the I30 family