H32 ICD-10-CM Code: Chorioretinal disorders in diseases classified elsewhere

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for H32 in the official ICD-10-CM tabular list, quoted as published.

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

Coder workflow for H32

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

Before you code H32

1. H32 is a manifestation code (“in diseases classified elsewhere”). Confirm the underlying condition is documented and sequence it first; a manifestation code is not reported as the first-listed or principal diagnosis. The etiology/manifestation convention (Guidelines I.A.13).

   See the official tabular notes · Guide: Manifestation codes and Code First sequencing →

2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with H32. 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 H32’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.

   ReviewB58.01, A18.53

2. Is the underlying (etiologic) condition the Code First note names documented?
   Yes → Sequence the underlying condition first, then H32.
   No → A manifestation code needs its underlying condition — query before reporting it.

   ReviewP37.1, B39, A30

Consider H32. Then 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).

The underlying (etiologic) condition

Named in the Code First note; sequenced before this code when documented (Guidelines I.A.13).

Official instructions as workflow

• Excludes1 — check before selecting H32(3 notes)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with H32: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareB58.01, A18.53

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

• Code First — sequencing check(4 notes)

  Coding workflow: Check whether the underlying or etiologic condition the note names is documented. When it is, sequence it before H32. Do not add an underlying condition the record does not document.

  ReviewP37.1, B39, A30

  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.

Don’t confuse H32 with…

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

The codes most likely to be picked instead of H32 — 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.

• B58.01— 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 toxoplasmosis (acquired) moves the case to B58.01; the two are not reported together unless documented as unrelated.

  Full comparison: H32 vs B58.01 →

• A18.53— 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 tuberculosis moves the case to A18.53; the two are not reported together unless documented as unrelated.

  Full comparison: H32 vs A18.53 →

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

• Principal-diagnosis restriction. This is a manifestation code: the Medicare Code Editor requires the underlying condition (etiology) to be sequenced first, with this code reported after it.

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 H32 or its code family, from the CMS ICD-10-CM tabular instructional notes and the CMS ICD-10-CM Index to Diseases and Injuries. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Use Additional Code instruction: B39 — Histoplasmosis.

These codes instruct coders to additionally report this code when it applies.

Referenced by 2 Index etiology/manifestation pairs across 2 chapters: A50.01 — Early congenital syphilitic oculopathy, N18.9 — Chronic kidney disease, unspecified.

The ICD-10-CM Index lists these etiology codes with this code in brackets — the manifestation, reported second.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 2 MS-DRGs: DRG 124 (MDC 02), DRG 125 (MDC 02).

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

Clinical classification (AHRQ CCSR):EYE005 — Retinal and vitreous conditions.

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

Related Codes

Principal diagnosis restriction (Medicare Code Editor)

Manifestation code — the underlying condition is sequenced first.

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Retinal and vitreous conditions).

+747 more

Contextual Map

Every relationship of H32 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 H32 with these 5 related codes in Claim Check

Hierarchy

• H00-H59 — Chapter 7: Diseases of the Eye and Adnexa (H00-H59) (H00-H59)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• H30-H36 — Disorders of choroid and retina[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Excludes1

• A18.53 — Tuberculous chorioretinitis[Excludes1]: “tuberculosis (A18.53)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• B58.01 — Toxoplasma chorioretinitis[Excludes1]: “toxoplasmosis (acquired) (B58.01)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Code First

• A30 — Leprosy [Hansen's disease][Code First]: “leprosy (A30.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• B39 — Histoplasmosis[Code First]: “histoplasmosis (B39.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• P37.1 — Congenital toxoplasmosis[Code First]: “congenital toxoplasmosis (P37.1)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Use Additional Code instructions

• B39 — Histoplasmosis[Use Additional Code]: “retinitis (H32)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Index etiology/manifestation pairs

• A50.01 — Early congenital syphilitic oculopathy[Index manifestation]: “Retinitis, syphilitic, congenital”— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• N18.9 — Chronic kidney disease, unspecified[Index manifestation]: “Retinitis, renal”— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Clinical classification (CCSR)

• EYE005 — Retinal and vitreous conditions[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

MS-DRG Grouper

• DRG 124 — OTHER DISORDERS OF THE EYE WITH MCC OR THROMBOLYTIC AGENT[MS-DRG]: “OTHER DISORDERS OF THE EYE WITH MCC OR THROMBOLYTIC AGENT (MDC 02)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 125 — OTHER DISORDERS OF THE EYE WITHOUT MCC[MS-DRG]: “OTHER DISORDERS OF THE EYE WITHOUT MCC (MDC 02)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

• MDC 02 — Diseases and Disorders of the Eye[MDC crossing]: “Diseases and Disorders of the Eye — 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. 1,200 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · 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