2026 ICD-10-CM Diagnosis Code H31.21Choroideremia

ICD-10-CM Codes›H00–H59›H30-H36›H31

ICD-10-CM H31.21
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

H31.21 is a billable ICD-10-CM diagnosis code for choroideremia. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 124 through 125. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Retinal and vitreous conditions.

Code Identity

ICD-10-CM Code
H31.21
Billable Status
Yes — Valid for Submission
Code Describes
Choroideremia
Short Description
Choroideremia
Same as the full description in the CMS dataset.
Parent Code
H31.2
Hereditary choroidal dystrophy

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH30-H36Disorders of choroid and retina
CategoryH31Other disorders of choroid
This CodeH31.21Choroideremia

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bilateral choroid degeneration
  • Bilateral choroideremia of eyes
  • Choroideremia
  • Choroideremia with deafness and obesity syndrome
  • Congenital mixed conductive and sensorineural hearing loss
  • Hereditary choroidal dystrophy
  • Mixed conductive AND sensorineural hearing loss
  • X-linked sensorineural hearing loss

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Choroideremia
    • Dystrophy, dystrophia
      • choroid (hereditary)
        • choroideremia

Clinical ClassificationClinical

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

CCSR EYE005
Retinal and vitreous conditions
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Choroideremia

    an x chromosome-linked abnormality characterized by atrophy of the choroid and degeneration of the retinal pigment epithelium causing night blindness.

Patient EducationClinical

Eye Diseases

Even if your eyes feel healthy, you could have a problem and not know it. That's why regular eye exams are so important. Refractive errors are the most common type of vision problem that makes it hard to see clearly. But some eye conditions or diseases don't have any symptoms and can lead to a permanent loss of vision.

The full article covers:

  • What diseases can affect the eye?
  • What are the symptoms of eye diseases?
  • Who is more likely to develop eye diseases?
  • What are the treatments for eye diseases?
  • Can eye diseases be prevented?

Read the full article at MedlinePlus

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

Convert H31.21 to ICD-9-CMHistory

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

ICD-9-CM
363.55 Choroideremia
Exact Match The mapping is direct, with no qualifiers.

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 H31.21Overview

Is H31.21 (Hereditary choroidal dystrophy) a billable code?

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

What MS-DRG does H31.21 group to?

When choroideremia is the principal diagnosis on an inpatient stay, it groups to MS-DRG 124, 125, with relative weights from 0.7678 to 1.3231 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of H31.21?

Under the General Equivalence Mappings, choroideremia converts to ICD-9-CM 363.55 (choroideremia). The mapping is a direct match.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.