R65.21 — Severe sepsis with septic shock
Is R65.21 billable?
Yes — R65.21 is billable for FY2027. R65.21 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. R65.21 may be submitted for encounters from October 1, 2026 through September 30, 2027.
R65.21 at a glance
| Code | R65.21 |
|---|---|
| Description | Severe sepsis with septic shock |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
What Medicare edits apply to R65.21?
The Medicare Code Editor screens inpatient claims before they are grouped. These edits name R65.21 directly.
CMS will reject this code as the principal diagnosis on an inpatient claim. It describes something other than the condition chiefly responsible for the admission.
Which MS-DRGs does R65.21 group to?
R65.21 sits in MDC 18 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 870Septicemia or Severe Sepsis with MV >96 Hoursmedical
- 871Septicemia or Severe Sepsis without MV >96 Hours with MCCmedical
- 872Septicemia or Severe Sepsis without MV >96 Hours without MCCmedical
As a secondary diagnosis, R65.21 is a major complication or comorbidity (MCC), which can move a stay into a higher-paying DRG.
How is R65.21 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to R65.21. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Severe sepsis › with septic shock
- Shock › endotoxic
- Shock › gram-negative
- Shock › septic
- Sepsis › severe › with septic shock (generalized) (unspecified organism)
- Infection, infected, infective › with › organ dysfunction › with septic shock (opportunistic)
- Sepsis › with › organ dysfunction › with septic shock (generalized) (unspecified organism)
Excludes1 — never code together
The conditions below can never be reported together with R65.21 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- postprocedural septic shock (T81.12-)
Code first — inherited from R65.2
The underlying condition below must be sequenced before R65.21. R65.21 describes a manifestation and cannot be the principal or first-listed diagnosis.
- underlying infection, such as:
- infection following a procedure (T81.4-)
- infections following infusion, transfusion and therapeutic injection (T80.2-)
- puerperal sepsis (O85)
- sepsis following complete or unspecified spontaneous abortion (O03.87)
- sepsis following ectopic and molar pregnancy (O08.82)
- sepsis following incomplete spontaneous abortion (O03.37)
- sepsis following (induced) termination of pregnancy (O04.87)
- sepsis NOS (A41.9)
Use additional code — inherited from R65.2
Report an additional code alongside R65.21 to fully describe the condition. R65.21 is sequenced first.
- code to identify specific acute organ dysfunction, such as:
- acute kidney failure (N17.-)
- acute respiratory failure (J96.0-)
- critical illness myopathy (G72.81)
- critical illness polyneuropathy (G62.81)
- disseminated intravascular coagulopathy [DIC] (D65)
- encephalopathy (metabolic) (septic) (G93.41)
- hepatic failure (K72.0-)
Excludes2 — not included here — inherited from Chapter 18
The conditions below are not part of R65.21, but a patient may have both at the same time. When documentation supports it, R65.21 and the excluded code may both be reported.
How long has R65.21 existed?
R65.21 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.