O85 vs O86.4
O85 and O86.4 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
The official note, declared on O85
fever of unknown origin following delivery (O86.4)
O85
Puerperal sepsis
Billable
- Chapter 15
- Pregnancy, childbirth and the puerperium
- Section
- O85-O92
Use when the record says
- Postpartum sepsis
- Puerperal peritonitis
- Puerperal pyemia
Indexed under
- Pelviperitonitis › puerperal
- Peritonitis › puerperal, postpartum, childbirth (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion)
- Puerperal, puerperium › metroperitonitis (complicated by, complications)
- Puerperal, puerperium › parametritis (complicated by, complications)
- Puerperal, puerperium › pelviperitonitis (complicated by, complications)
O86.4
Pyrexia of unknown origin following delivery
Billable
- Chapter 15
- Pregnancy, childbirth and the puerperium
- Section
- O85-O92
Use when the record says
- Puerperal infection NOS following delivery
- Puerperal pyrexia NOS following delivery
Indexed under
- Fever › following delivery (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Fever › puerperal (inanition) (of unknown origin) (persistent) (with chills) (with rigor)
- Infection, infected, infective › puerperal (opportunistic)
- Puerperal, puerperium › fever (complicated by, complications)
- Puerperal, puerperium › infection (complicated by, complications)
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027