B25.9 vs B34
B25.9 (Cytomegaloviral disease, unspecified) compared with B34 (Viral infection of unspecified site), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. B34 carries an Excludes1 note covering B25.9: “cytomegaloviral disease NOS (B25.9)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| B25.9Cytomegaloviral disease, unspecified | B34Viral infection of unspecified site | |
|---|---|---|
| Billing status | Billable | Non-billable header |
| Classification | A00-B99 — Certain Infectious and Parasitic Diseases (A00-B99) | A00-B99 — Certain Infectious and Parasitic Diseases (A00-B99) |
| Definition | Cytomegaloviral disease, unspecified is a billable ICD-10-CM diagnosis code (B25.9). | Viral infection of unspecified site is a non-billable ICD-10-CM category code (B34). |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources