ICD-10-CM 2027
ICD-10 code for keratitis
From the official ICD-10-CM alphabetic index entry “Keratitis (nodular) (nonulcerative) (simple) (zonular)”. Page updated September 29, 2026.
About coding keratitis
The ICD-10-CM code for keratitis is H16.9 (Unspecified keratitis). The official index lists 51 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on H16.9.
Within H16, choose H16.9 (Unspecified keratitis) only when documentation doesn't support a more specific option: corneal ulcer (H16.0), other and unspecified superficial keratitis without conjunctivitis (H16.1), keratoconjunctivitis (H16.2), interstitial and deep keratitis (H16.3), corneal neovascularization (H16.4) and other keratitis (H16.8).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 124 (Other Disorders of the Eye with MCC or Thrombolytic Agent, relative weight 1.2471) and DRG 125 (Other Disorders of the Eye without MCC, relative weight 0.7702), in MDC 02 (Diseases and Disorders of the Eye), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific keratitis codes (official index)
- with ulceration (central) (marginal) (perforated) (ring)
- actinic
- arborescens (herpes simplex) B00.52 — Herpesviral keratitis
- areolar H16.11 — Macular keratitis
- bullosa H16.8 — Other keratitis
- deep H16.309 — Unspecified interstitial keratitis, unspecified eye
- specified type NEC H16.399 — Other interstitial and deep keratitis, unspecified eye
- dendritic (a) (herpes simplex) B00.52 — Herpesviral keratitis
- disciform (is) (herpes simplex) B00.52 — Herpesviral keratitis
- varicella B01.81 — Varicella keratitis
- filamentary H16.12 — Filamentary keratitis
- gonococcal (congenital or prenatal) A54.33 — Gonococcal keratitis
- herpes, herpetic (simplex) B00.52 — Herpesviral keratitis
- zoster B02.33 — Zoster keratitis
- in (due to)
- acanthamebiasis B60.13 — Keratoconjunctivitis due to Acanthamoeba
- adenovirus B30.0 — Keratoconjunctivitis due to adenovirus
- exanthema B09 — Unspecified viral infection characterized by skin and mucous membrane lesions
- herpes (simplex) virus B00.52 — Herpesviral keratitis
- measles B05.81 — Measles keratitis and keratoconjunctivitis
- syphilis A50.31 — Late congenital syphilitic interstitial keratitis
- tuberculosis A18.52 — Tuberculous keratitis
- zoster B02.33 — Zoster keratitis
- interstitial (nonsyphilitic) H16.30 — Unspecified interstitial keratitis
- diffuse H16.32 — Diffuse interstitial keratitis
- herpes, herpetic (simplex) B00.52 — Herpesviral keratitis
- zoster B02.33 — Zoster keratitis
- sclerosing H16.33 — Sclerosing keratitis
- specified type NEC H16.39 — Other interstitial and deep keratitis
- syphilitic (congenital) (late) A50.31 — Late congenital syphilitic interstitial keratitis
- tuberculous A18.52 — Tuberculous keratitis
- macular H16.11 — Macular keratitis
- nummular H16.11 — Macular keratitis
- oyster shuckers' H16.8 — Other keratitis
- parenchymatous
- petrificans H16.8 — Other keratitis
- postmeasles B05.81 — Measles keratitis and keratoconjunctivitis
- punctata
- leprosa A30.9 — Leprosy, unspecified
- syphilitic (profunda) A50.31 — Late congenital syphilitic interstitial keratitis
- punctate H16.14 — Punctate keratitis
- purulent H16.8 — Other keratitis
- rosacea L71.8 — Other rosacea
- sclerosing H16.33 — Sclerosing keratitis
- specified type NEC H16.8 — Other keratitis
- stellate H16.11 — Macular keratitis
- striate H16.11 — Macular keratitis
- superficial H16.10 — Unspecified superficial keratitis
- with conjunctivitis
- due to light
- suppurative H16.8 — Other keratitis
- syphilitic (congenital) (prenatal) A50.31 — Late congenital syphilitic interstitial keratitis
- trachomatous A71.1 — Active stage of trachoma
- sequelae B94.0 — Sequelae of trachoma
- tuberculous A18.52 — Tuberculous keratitis
- vesicular H16.8 — Other keratitis
- xerotic H16.8 — Other keratitis
- vitamin A deficiency E50.4 — Vitamin A deficiency with keratomalacia
Common questions about keratitis ICD-10 codes
What is the ICD-10 code for keratitis?
- H16.9 — Unspecified keratitis. More specific codes apply when the documentation supports them: B00.52, H16.11, H16.8, H16.309 and others below.
What is the ICD-10 code for arborescens keratitis?
- B00.52 — Herpesviral keratitis.
What is the ICD-10 code for areolar keratitis?
- H16.11 — Macular keratitis (header code; choose a more specific subcode).
What is the ICD-10 code for bullosa keratitis?
- H16.8 — Other keratitis.
What is the ICD-10 code for deep keratitis?
- H16.309 — Unspecified interstitial keratitis, unspecified eye.
What is the ICD-10 code for dendritic keratitis?
- B00.52 — Herpesviral keratitis.
What is the ICD-10 code for disciform keratitis?
- B00.52 — Herpesviral keratitis.
Is H16.9 billable?
- Yes. H16.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can H16.9 be used as a principal diagnosis?
- No. It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
Is H16.9 a CC or MCC?
- No. H16.9 is neither a CC nor an MCC under MS-DRG v44.0.