2027 ICD-10-CM Diagnosis Code B05.81Measles keratitis and keratoconjunctivitis

ICD-10-CM Codes›A00–B99›B00-B09›B05

ICD-10-CM B05.81
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

B05.81 is a billable ICD-10-CM diagnosis code for measles keratitis and keratoconjunctivitis. 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, 791, 793. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 22 closely related codes. Coders also document this condition as measles keratitis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Cornea and external disease and Viral infection.

Code Identity

ICD-10-CM Code
B05.81
Billable Status
Yes — Valid for Submission
Code Describes
Measles keratitis and keratoconjunctivitis
Short Description
Measles keratitis and keratoconjunctivitis
Same as the full description in the CMS dataset.
Parent Code
B05.8
Measles with other complications

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB00-B09Viral infections characterized by skin and mucous membrane lesions
CategoryB05Measles
This CodeB05.81Measles keratitis and keratoconjunctivitis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Measles keratitis
  • Measles keratoconjunctivitis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to B05.81: its own notes plus those printed at B05 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From B05 Measles applies to 8 codes
  • morbilli
From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From B05 Measles applies to 8 codes
  • subacute sclerosing panencephalitis (A81.1)

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 Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

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

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

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
CCSR INF008
Viral infection
Default principal diagnosis: inpatient No · outpatient No

Clinical InformationClinical

  • Measles

    a highly contagious infectious disease caused by morbillivirus, common among children but also seen in the nonimmune of any age, in which the virus enters the respiratory tract via droplet nuclei and multiplies in the epithelial cells, spreading throughout the mononuclear phagocyte system.

Patient EducationClinical

Measles

Measles is an infectious disease caused by a virus. It spreads easily from person to person. It causes a blotchy red rash. The rash often starts on the head and moves down the body. Other symptoms include:

Read the full article at MedlinePlus

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

Convert B05.81 to ICD-9-CMHistory

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

ICD-9-CM
055.71 Measles keratitis
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About B05.81Overview

What is the ICD-10 code for measles keratitis and keratoconjunctivitis?

The ICD-10-CM code for measles keratitis and keratoconjunctivitis is B05.81 (sometimes written as B0581). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is B05.81 (Measles with other complications) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report measles keratitis and keratoconjunctivitis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does B05.81 group to?

When measles keratitis and keratoconjunctivitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 125, 124, with relative weights from 0.7699 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.

Is B05.81 a CC or MCC?

CMS lists B05.81 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 22 closely related codes in its exclusion list.

Can B05.81 be reported with A81.1?

Not as a rule. The Excludes1 note at B05, which applies to B05.81, lists "subacute sclerosing panencephalitis (A81.1)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).