B27.0 vs G63
B27.0 (Gammaherpesviral mononucleosis) compared with G63 (Polyneuropathy in diseases classified elsewhere), 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. G63 carries an Excludes1 note covering B27.0: “infectious mononucleosis complicated by polyneuropathy (B27.0-B27.9 with fifth character 1)”
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
| B27.0Gammaherpesviral mononucleosis | G63Polyneuropathy in diseases classified elsewhere | |
|---|---|---|
| Billing status | Non-billable header | Billable |
| Classification | A00-B99 — Certain Infectious and Parasitic Diseases (A00-B99) | G00-G99 — Diseases of the Nervous System (G00-G99) |
| Definition | Gammaherpesviral mononucleosis is a non-billable ICD-10-CM category code (B27.0). | Polyneuropathy in diseases classified elsewhere is a billable ICD-10-CM diagnosis code (G63). |
| Includes | glandular fever monocytic angina Pfeiffer's disease Mononucleosis due to Epstein-Barr virus | — |
| Code first | — | underlying disease, such as: amyloidosis (E85.-) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources