K65 vs O00
K65 (Peritonitis) compared with O00 (Ectopic pregnancy), 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. K65 carries an Excludes1 note covering O00: “peritonitis with or following abortion or ectopic or molar pregnancy (O00-O07, O08.0)”
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
| K65Peritonitis | O00Ectopic pregnancy | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | K00-K95 — Diseases of the Digestive System (K00-K95) | O00-O9A — Pregnancy, Childbirth and the Puerperium (O00-O9A) |
| Definition | Peritonitis is a non-billable ICD-10-CM category code (K65). | Ectopic pregnancy is a non-billable ICD-10-CM category code (O00). |
| Includes | — | ruptured ectopic pregnancy |
| Use additional code | code (B95-B97), to identify infectious agent, if known | code from category O08 to identify any associated complication |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources