N61 vs O91
N61 (Inflammatory disorders of breast) compared with O91 (Infections of breast associated with pregnancy, the puerperium and lactation), 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. N61 carries an Excludes1 note covering O91: “inflammatory disorder of breast associated with childbirth (O91.-)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
No — do not report together. N61 carries an Excludes1 note covering O91: “disorders of breast associated with childbirth (O91-O92)”
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
| N61Inflammatory disorders of breast | O91Infections of breast associated with pregnancy, the puerperium and lactation | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | N00-N99 — Diseases of the Genitourinary System (N00-N99) | O00-O9A — Pregnancy, Childbirth and the Puerperium (O00-O9A) |
| Definition | Inflammatory disorders of breast is a non-billable ICD-10-CM category code (N61). | Infections of breast associated with pregnancy, the puerperium and lactation is a non-billable ICD-10-CM category code (O91). |
| Use additional code | — | code to identify infection |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources