B27 vs G02
B27 (Infectious mononucleosis) compared with G02 (Meningitis in other infectious and parasitic 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. G02 carries an Excludes1 note covering B27: “infectious mononucleosis complicated by meningitis (B27.- with fifth character 2)”
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
| B27Infectious mononucleosis | G02Meningitis in other infectious and parasitic 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 | Infectious mononucleosis is a non-billable ICD-10-CM category code (B27). | Meningitis in other infectious and parasitic diseases classified elsewhere is a billable ICD-10-CM diagnosis code (G02). |
| Includes | glandular fever monocytic angina Pfeiffer's disease | — |
| Code first | — | underlying disease, such as: African trypanosomiasis (B56.-) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources