ICD-10-CM 2027 diagnosis code

B25Cytomegaloviral disease

Not billable — use a more specific code

B25 is a header code, so it can't be reported by itself. Choose one of the 5 more specific codes beneath it.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About B25

B25 is the ICD-10-CM diagnosis code for cytomegaloviral disease. It belongs to block B25-B34 (other viral diseases) and chapter 1 (certain infectious and parasitic diseases). It is a header code, so it can't be reported by itself; one of its 5 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: B25.0 (pneumonitis), B25.1 (hepatitis), B25.2 (pancreatitis), B25.8 (diseases) and B25.9 (unspecified).

Don't report B25 together with the conditions in its Excludes1 note: congenital cytomegalovirus infection (P35.1) and cytomegaloviral mononucleosis (B27.1-).

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under B25

Coding notes

Excludes1Not coded here — never report together with this code

congenital cytomegalovirus infection (P35.1)
cytomegaloviral mononucleosis (B27.1-)

Notes that apply from higher levels

Instructions written at a parent level also apply to B25.

Broader instructions also apply from Chapter 1: Certain infectious and parasitic diseases.

Codes whose notes reference B25

B10Excludes2
T86.43Use additional code

Code history

2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about B25

Is B25 billable?: No. B25 is a header code. Report one of its more specific subcodes instead.