2027 ICD-10-CM Diagnosis Code H20.821Vogt-Koyanagi syndrome, right eye

ICD-10-CM Codes›H00–H59›H15-H22›H20

ICD-10-CM H20.821
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

H20.821 is a billable ICD-10-CM diagnosis code for Vogt-Koyanagi syndrome, right eye. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 124 through 125. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Uveitis and ocular inflammation.

Code Identity

ICD-10-CM Code
H20.821
Billable Status
Yes — Valid for Submission
Code Describes
Vogt-Koyanagi syndrome, right eye
Short Description
Vogt-Koyanagi syndrome, right eye
Same as the full description in the CMS dataset.
Parent Code
H20.82
Vogt-Koyanagi syndrome

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH15-H22Disorders of sclera, cornea, iris and ciliary body
CategoryH20Iridocyclitis
This CodeH20.821Vogt-Koyanagi syndrome, right eye

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to H20.821: its own notes plus those printed at H20.8 and Chapter 7. A note printed at a category, block or chapter applies to every code under it.

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From H20.8 Other iridocyclitis applies to 8 codes
From Chapter 7 (H00-H59) Diseases of the eye and adnexa applies to 2,677 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • diabetes mellitus related eye conditions (E09.3-, E10.3-, E11.3-, E13.3-)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury (trauma) of eye and orbit (S05.-)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • syphilis related eye disorders (A50.01, A50.3-, A51.43, A52.71)

Notes

General instructions on how these codes are used.

From Chapter 7 (H00-H59) Diseases of the eye and adnexa applies to 2,677 codes
  • Use an external cause code following the code for the eye condition, if applicable, to identify the cause of the eye condition

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Clinical ClassificationClinical

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

CCSR EYE004
Uveitis and ocular inflammation
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Iridocyclitis

    acute or chronic inflammation of the iris and ciliary body characterized by exudates into the anterior chamber, discoloration of the iris, and constricted, sluggish pupil. symptoms include radiating pain, photophobia, lacrimation, and interference with vision.

Patient EducationClinical

Eye Diseases

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Read the full article at MedlinePlus

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

Convert H20.821 to ICD-9-CMHistory

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

ICD-9-CM
364.24 Vogt-koyanagi syndrome
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About H20.821Overview

What is the ICD-10 code for Vogt-Koyanagi syndrome, right eye?

The ICD-10-CM code for Vogt-Koyanagi syndrome, right eye is H20.821 (sometimes written as H20821). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is H20.821 (Vogt-Koyanagi syndrome) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report Vogt-Koyanagi syndrome, right eye on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does H20.821 group to?

When Vogt-Koyanagi syndrome, right eye is the principal diagnosis on an inpatient stay, it groups to MS-DRG 125, 124, with relative weights from 0.7699 to 1.2470 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of H20.821?

Under the General Equivalence Mappings, Vogt-Koyanagi syndrome, right eye converts to ICD-9-CM 364.24 (vogt-koyanagi syndrome). The mapping is approximate, so confirm the match fits the documentation.