2026 ICD-10-CM Diagnosis Code H16.209Unspecified keratoconjunctivitis, unspecified eye

ICD-10-CM Codes›H00–H59›H15-H22›H16

ICD-10-CM H16.209
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

H16.209 is a billable ICD-10-CM diagnosis code for unspecified keratoconjunctivitis, unspecified eye. 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. Coders also document this condition as keratoconjunctivitis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Cornea and external disease.

Code Identity

ICD-10-CM Code
H16.209
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified keratoconjunctivitis, unspecified eye
Short Description
Unspecified keratoconjunctivitis, unspecified eye
Same as the full description in the CMS dataset.
Parent Code
H16.20
Unspecified keratoconjunctivitis

Code Classification

ChapterH00–H59Diseases of the eye and adnexa
SectionH15-H22Disorders of sclera, cornea, iris and ciliary body
CategoryH16Keratitis
This CodeH16.209Unspecified keratoconjunctivitis, unspecified eye

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Keratoconjunctivitis
  • Keratoconjunctivitis caused by molluscum contagiosum
  • Molluscum contagiosum infection

Clinical ClassificationClinical

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

CCSR EYE001
Cornea and external disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Conjunctivitis, Allergic

    conjunctivitis due to hypersensitivity to various allergens.

  • Keratoconjunctivitis

    simultaneous inflammation of the cornea and conjunctiva.

  • Keratoconjunctivitis Sicca

    drying and inflammation of the conjunctiva as a result of insufficient lacrimal secretion. when found in association with xerostomia and polyarthritis, it is called sjogren's syndrome.

  • Keratoconjunctivitis, Infectious

    infectious diseases of cattle, sheep, and goats, characterized by blepharospasm, lacrimation, conjunctivitis, and varying degrees of corneal opacity and ulceration. in cattle the causative agent is moraxella (moraxella) bovis; in sheep, mycoplasma; rickettsia; chlamydia; or acholeplasma; in goats, rickettsia.

  • Dry Eye Syndrome|Dry Eye|Dry Eye(s)|Dry eye|Keratoconjunctivitis Sicca

    a syndrome characterized by dryness of the cornea and conjunctiva. it is usually caused by a deficiency in tear production. symptoms include a feeling of burning eyes and a possible foreign body presence in the eye.

  • Epidemic Keratoconjunctivitis

    keratoconjunctivitis resulting from infection by adenoviruses.

  • Keratoconjunctivitis

    inflammation of both the cornea and the conjunctiva.

  • Sicca Syndrome with Keratoconjunctivitis|Sicca syndrome with keratoconjunctivitis

    evidence of sicca syndrome with keratoconjunctivitis.

  • Dry Eyes, Ped-PRO-CTCAE|Dry Eye, Ped-PRO-CTCAE|Dry eyes|Keratoconjunctivitis Sicca, Ped-PRO-CTCAE|Ped-PRO-CTCAE, Dry Eyes

    keratoconjunctivitis sicca as recorded on the ped-pro-ctcae questionnaire.

Patient EducationClinical

Corneal Disorders

Your cornea is the outermost layer of your eye. It is clear and shaped like a dome. The cornea helps to shield the rest of the eye from germs, dust, and other harmful matter. It also helps your eye to focus. If you wear contact lenses, they float on top of your corneas.

Read the full article at MedlinePlus

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

Convert H16.209 to ICD-9-CMHistory

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

ICD-9-CM
370.40 Keratoconjunctivitis NOS
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 H16.209Overview

Is H16.209 (Unspecified keratoconjunctivitis) a billable code?

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

What MS-DRG does H16.209 group to?

When unspecified keratoconjunctivitis, unspecified eye 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 H16.209?

Under the General Equivalence Mappings, unspecified keratoconjunctivitis, unspecified eye converts to ICD-9-CM 370.40 (keratoconjunctivitis NOS). 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.