B27.1 – Cytomegaloviral mononucleosis
ICD-10-CM 2027 diagnosis code · Other viral diseases
ICD-10-CM code
B27.1
- Code
B27.1(claims format:B271)- Description
- Cytomegaloviral mononucleosis
- Billable
- No – use a more specific code below
- Valid for
- Dates of service October 1, 2026 – September 30, 2027 (FY2027)
- Chapter
- 1. Certain infectious and parasitic diseases (A00-B99)
- Block
- B25-B34 Other viral diseases
- Parent codes
- B27
Billable codes under B27.1
B27.1 is a header code and cannot be used on claims. Choose the most specific code:
Notes inherited from parent codes
Instructional notes at a category or block level apply to every code below it.
B27 – Infectious mononucleosis
Includes:
- glandular fever
- monocytic angina
- Pfeiffer's disease
Related codes in B27
Frequently asked questions
What is ICD-10 code B27.1?
B27.1 is the ICD-10-CM code for cytomegaloviral mononucleosis, in the block B25-B34 (Other viral diseases).
Is B27.1 a billable code?
No. B27.1 is a header code with more specific child codes; report one of the billable codes listed above.
What category does B27.1 belong to?
It belongs to category B27 – Infectious mononucleosis.
Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.