A41.9 ICD-10-CM Code: Sepsis, unspecified organism

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for A41.9 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on A41.9 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for A41.9

MedCoder structured workflow — derived from this code’s own official record

Before you code A41.9

1. Unspecified does not mean incorrect. When the record gives no greater specificity, A41.9 may be the appropriate code. Check the record for detail that supports a more specific sibling. An unspecified code is for records that do not provide the detail a more specific code needs; a query, not an assumption, is the route to specificity (Guidelines I.A.9.b, I.B.18).

   ReviewA41.0, A41.1, A41.3, A41.4, A41.5, A41.8

   See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with A41.9. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

   See the official tabular notes

Choose the right path

1. Does the record document the detail a more specific sibling code needs?
   Yes → Review the specific siblings in this subcategory.
   No → Continue — A41.9 is appropriate when the documentation goes no further.

   ReviewA41.0, A41.1, A41.3, A41.4, A41.5, A41.8

2. Does the documentation support a condition named in A41.9’s Excludes1 note?
   Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
   No → Continue.

   ReviewR78.81, P36, O85, A40

3. Is the underlying (etiologic) condition the Code First note names documented?
   Yes → Sequence the underlying condition first, then A41.9.
   No → Continue; do not add an underlying condition the record does not document.

   ReviewT81.44, T80.211, O75.3, O03.37, O03.87, O04.87

Consider A41.9. Then confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement

Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).

The underlying (etiologic) condition

Named in the Code First note; sequenced before this code when documented (Guidelines I.A.13).

Any detail beyond this code’s title

What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

• Excludes1 — check before selecting A41.9(4 notes)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with A41.9: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareR78.81, P36, O85, A40

  See the official tabular notes · Guidelines I.A.12.a

• Excludes2 — not part of A41.9(13 notes)

  Coding workflow: The conditions named in this note are not included in A41.9. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareA42.7, A22.7, B37.7, A26.7, A28.2, A54.86

  See the official tabular notes · Guidelines I.A.12.b

• Code First — sequencing check(6 notes)

  Coding workflow: Check whether the underlying or etiologic condition the note names is documented. When it is, sequence it before A41.9. Do not add an underlying condition the record does not document.

  ReviewT81.44, T80.211, O75.3, O03.37, O03.87, O04.87

  See the official tabular notes · Guidelines I.A.13

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Before you code A41.9

MedCoder editorial — not official ICD-10-CM text; reviewed against the cited source

This checklist routes you to the categories to review — it does not determine the final code.

A41.9 is sepsis with the organism not further specified — the guideline’s own default when the type of infection or causal organism is not documented. The forks that matter run in three directions: a documented organism, a documented severity (organ dysfunction or shock), and a documented cause (procedure, device, pregnancy). Check for these before settling on A41.9.

• Causal organism or type of infection documented → the specific sepsis rows

  A41.9 is the default only when the organism is not further specified (I.C.1.d.1a); a documented organism selects its own row — streptococcal sepsis, for one, is an A41 Excludes1 routed to A40.-.

• Severe sepsis, or an acute organ dysfunction associated with the sepsis, documented → R65.2- Severe sepsis, as the SECOND code

  Severe sepsis takes a minimum of two codes — the systemic infection first, then R65.2-, plus codes for each organ dysfunction (I.C.1.d.1b). R65.2- is never assigned without that documentation, and never as principal.

• Septic shock documented → R65.21 Severe sepsis with septic shock

  The infection code is sequenced first, followed by R65.21 (postprocedural shock goes to T81.12- instead); the shock code cannot be principal (I.C.1.d.2).

• Sepsis documented as postprocedural or due to a device or infusion → the T81.44-/T80.2- code-first rows

  Category A41 carries a Code First note for postprocedural sepsis, central-line sepsis, and the transfusion/injection rows — the complication code leads when the record ties the sepsis to the procedure or device.

• Sepsis in pregnancy, childbirth, or the puerperium → O85 Puerperal sepsis and the obstetric rows

  Puerperal sepsis is an A41 Excludes1, and the Code First note names the labor/abortion rows — chapter 15 leads those encounters.

• "Bacteremia" documented, without a sepsis diagnosis → R78.81 Bacteremia

  Bacteremia NOS is an A41 Excludes1 — a laboratory finding of organisms in the blood is not, by itself, the diagnosis of sepsis.

• "Urosepsis" documented → a provider query

  The guideline is unusually direct: urosepsis is a nonspecific term, not synonymous with sepsis, with no default code — the provider must be queried for clarification (I.C.1.d.1a.ii).

The two-code minimum, the sequencing rules, and the query triggers are worked through in the sepsis guide. Sepsis, Severe Sepsis, and Septic Shock Coding →

Provider documentation and the ICD-10-CM Official Guidelines control; verify against the official tabular notes on this page.

Indexed Clinical Terms (7)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

• Disorder (of), tubulo-interstitial (in), sepsis
• Glomerulonephritis, in (due to), sepsis
• Pyelonephritis, in (due to), sepsis
• Sepsis (generalized) (unspecified organism)
• Sepsis (generalized) (unspecified organism), cryptogenic
• Sepsis (generalized) (unspecified organism), gangrenous
• Septicemia

Official Coding Guidelines

Official source data — quoted verbatim from the CMS/NCHS Official Guidelines

Official source data — quoted verbatim from the CMS/NCHS Official Guidelines

Verbatim excerpts from the ICD-10-CM Official Guidelines for Coding and Reporting (CMS/NCHS) that govern this code.

Coding Notes

MedCoder editorial — not official ICD-10-CM text; reviewed against the cited source

What this code means

A41.9 is the guideline’s named default: for a diagnosis of sepsis, code the underlying systemic infection, and when the type of infection or causal organism is not further specified, assign A41.9. Everything above that floor is documentation-driven. A documented organism selects a specific row; documented severe sepsis or an associated acute organ dysfunction adds R65.2- as a mandatory second code with the dysfunction codes behind it; a documented procedural or device cause puts a T81.44-/T80.2- complication code in front. What the code never does is stretch to cover findings: bacteremia is its own R-code, and "urosepsis" supports no code at all until the provider clarifies it.

Coding guidance

• Severe sepsis is a two-code minimum — the systemic infection first, then R65.2-, then a code for each documented acute organ dysfunction (I.C.1.d.1b). A code from R65.2- can never be principal.
• The organ dysfunction must be ASSOCIATED with the sepsis: dysfunction the record ties to another condition takes no R65.2- code, and unclear linkage is a query (I.C.1.d.1a.iv).
• Negative or inconclusive blood cultures do not preclude a sepsis diagnosis — but the guideline directs a query there too (I.C.1.d.1a.i).
• Sepsis admitted with a localized infection (pneumonia, cellulitis): the systemic infection codes first, the localized infection follows as secondary (I.C.1.d.4).

Decision-rule scenarios

Scenarios state the decision rule, not a code assignment — code selection always follows the provider's documentation and the ICD-10-CM Official Guidelines.

Documentation checklist

• The causal organism or infection type, which moves the code off the unspecified default.
• Severity wording — severe sepsis, any acute organ dysfunction, septic shock — and whether the dysfunction is tied to the sepsis.
• Any procedural, device, infusion, or obstetric cause the Code First note names.
• The localized infection accompanying the sepsis, for the secondary code.

Codes are assigned from provider documentation; a coder never infers a diagnosis.

Common mistakes

• Adding R65.2- without documented severe sepsis or an associated organ dysfunction — the guideline forbids it, and the reverse omission (documented dysfunction with no R65.2-) understates the claim.
• Sequencing R65.20/R65.21 first — the underlying systemic infection always leads, and R65.2- can never be principal.
• Coding "urosepsis" as A41.9 or N39.0 without a query — the term supports neither.
• Coding bacteremia as sepsis — R78.81 is a finding, and an A41 Excludes1.
• Missing the Code First rows when the record ties the sepsis to a procedure, device, or pregnancy.

Written and reviewed by MedCoder against the official ICD-10-CM files; educational, not medical or billing advice. The official tabular notes and guidelines above take precedence in every case.

Don’t confuse A41.9 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of A41.9 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

• R78.81— Excludes1 conflict (Excludes1 — generally not reported together)

  Not coded here — the tabular list excludes this pair for the same encounter.

  Not reported together with this code, except where the two conditions are documented as unrelated.

  What moves you there: Documentation of bacteremia NOS moves the case to R78.81; the two are not reported together unless documented as unrelated.

  Full comparison: A41.9 vs R78.81 →

• P36— Excludes1 conflict (Excludes1 — generally not reported together)

  Not coded here — the tabular list excludes this pair for the same encounter.

  Not reported together with this code, except where the two conditions are documented as unrelated.

  What moves you there: Documentation of neonatal moves the case to P36; the two are not reported together unless documented as unrelated.

  Full comparison: A41.9 vs P36 →

• O85— Excludes1 conflict (Excludes1 — generally not reported together)

  Not coded here — the tabular list excludes this pair for the same encounter.

  Not reported together with this code, except where the two conditions are documented as unrelated.

  What moves you there: Documentation of puerperal sepsis moves the case to O85; the two are not reported together unless documented as unrelated.

  Full comparison: A41.9 vs O85 →

• A40— Excludes1 conflict (Excludes1 — generally not reported together)

  Not coded here — the tabular list excludes this pair for the same encounter.

  Not reported together with this code, except where the two conditions are documented as unrelated.

  What moves you there: Documentation of streptococcal sepsis moves the case to A40; the two are not reported together unless documented as unrelated.

  Full comparison: A41.9 vs A40 →

• A42.7— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of sepsis (due to) (in) actinomycotic adds A42.7; it is not part of this code and both may be reported when both are documented.

  Full comparison: A41.9 vs A42.7 →

• A22.7— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of sepsis (due to) (in) anthrax adds A22.7; it is not part of this code and both may be reported when both are documented.

  Full comparison: A41.9 vs A22.7 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

1. Sequencing: 6 Code First instructions — the underlying condition is sequenced before this code when present. See the Code First notes
2. 4 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
3. 13 Excludes2 entries — those conditions are not part of this code and may be reported additionally when documented. See the Excludes2 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

Verify Before Coding

• MCC as a secondary diagnosis (FY2026). Can raise the stay's MS-DRG severity tier.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name A41.9 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Excludes1 note: A48.3 — Toxic shock syndrome.

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 4 Code First instructions across 3 chapters: I5A — Non-ischemic myocardial injury (non-traumatic) (via A41.-), N08 — Glomerular disorders in diseases classified elsewhere (via A41.-), N16 — Renal tubulo-interstitial disorders in diseases classified elsewhere (via A41.-), R65.2 — Severe sepsis.

Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.

Referenced by 7 Use Additional Code instructions across 3 chapters: J95.02 — Infection of tracheostomy stoma (via A41.-), K94.02 — Colostomy infection (via A41.-), K94.12 — Enterostomy infection (via A41.-), K94.22 — Gastrostomy infection (via A41.-), K95.01 — Infection due to gastric band procedure (via A41.-), K95.81 — Infection due to other bariatric procedure (via A41.-), T80.2 — Infections following infusion, transfusion and therapeutic injection.

These codes instruct coders to additionally report this code when it applies.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: MCC — Major Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 46 clinically related codes on its CMS exclusion list. Does not count toward severity when the stay groups to DRGs 974-976 (HIV with Major Related Condition).

Named in the grouper logic of 8 MS-DRGs: DRG 791 (MDC 15), DRG 793 (MDC 15), DRG 870 (MDC 18), DRG 871 (MDC 18), DRG 872 (MDC 18), DRG 974 (MDC 25), DRG 975 (MDC 25), DRG 976 (MDC 25).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):INF002 — Septicemia (default); INF003 — Bacterial infections.

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as MCC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

A41.3 — Sepsis due to Hemophilus influenzae, A41.4 — Sepsis due to anaerobes, A41.50 — Gram-negative sepsis, unspecified, A41.51 — Sepsis due to Escherichia coli [E. coli], A41.52 — Sepsis due to Pseudomonas, A41.53 — Sepsis due to Serratia, A41.54 — Sepsis due to Acinetobacter baumannii, A41.59 — Other Gram-negative sepsis, A41.81 — Sepsis due to Enterococcus, A41.89 — Other specified sepsis, A42.7 — Actinomycotic sepsis, A48.2 — Nonpneumonic Legionnaires' disease [Pontiac fever], A48.3 — Toxic shock syndrome, A48.4 — Brazilian purpuric fever, A48.8 — Other specified bacterial diseases, A49.01 — Methicillin susceptible Staphylococcus aureus infection, unspecified site, A49.02 — Methicillin resistant Staphylococcus aureus infection, unspecified site, A49.1 — Streptococcal infection, unspecified site, A49.2 — Hemophilus influenzae infection, unspecified site, A49.3 — Mycoplasma infection, unspecified site, +25 more

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock) for risk-adjusted payment.

A41.3 — Sepsis due to Hemophilus influenzae, A41.4 — Sepsis due to anaerobes, A41.50 — Gram-negative sepsis, unspecified, A41.51 — Sepsis due to Escherichia coli [E. coli], A41.52 — Sepsis due to Pseudomonas, A41.53 — Sepsis due to Serratia, A41.54 — Sepsis due to Acinetobacter baumannii, A41.59 — Other Gram-negative sepsis, A41.81 — Sepsis due to Enterococcus, A41.89 — Other specified sepsis, A42.7 — Actinomycotic sepsis, A48.3 — Toxic shock syndrome, A54.86 — Gonococcal sepsis, B00.7 — Disseminated herpesviral disease, B37.7 — Candidal sepsis, M35.81 — Multisystem inflammatory syndrome, P02.70 — Newborn affected by fetal inflammatory response syndrome, P36.0 — Sepsis of newborn due to streptococcus, group B, P36.10 — Sepsis of newborn due to unspecified streptococci, P36.19 — Sepsis of newborn due to other streptococci, +31 more

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Septicemia, Bacterial infections).

A41.3 — Sepsis due to Hemophilus influenzae, A41.4 — Sepsis due to anaerobes, A41.50 — Gram-negative sepsis, unspecified, A41.51 — Sepsis due to Escherichia coli [E. coli], A41.52 — Sepsis due to Pseudomonas, A41.53 — Sepsis due to Serratia, A41.54 — Sepsis due to Acinetobacter baumannii, A41.59 — Other Gram-negative sepsis, A41.81 — Sepsis due to Enterococcus, A41.89 — Other specified sepsis, A42.7 — Actinomycotic sepsis, A54.86 — Gonococcal sepsis, B37.7 — Candidal sepsis, O03.37 — Sepsis following incomplete spontaneous abortion, O03.87 — Sepsis following complete or unspecified spontaneous abortion, O04.87 — Sepsis following (induced) termination of pregnancy, O07.37 — Sepsis following failed attempted termination of pregnancy, O08.82 — Sepsis following ectopic and molar pregnancy, O85 — Puerperal sepsis, O86.04 — Sepsis following an obstetrical procedure, +392 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main terms “Sepsis”, “Glomerulonephritis”, “Pyelonephritis”; these codes share that main term but sit in a different category of the Tabular List.

A39.1 — Waterhouse-Friderichsen syndrome (adrenal hemorrhage syndrome), A39.2 — Acute meningococcemia (meningococcal, acute), A39.3 — Chronic meningococcemia (meningococcal, chronic), A39.4 — Meningococcemia, unspecified (meningococcal), A40 — Streptococcal sepsis (in, sepsis, streptococcal), A40.0 — Sepsis due to streptococcus, group A (Streptococcus, streptococcal, group, A), A40.1 — Sepsis due to streptococcus, group B (Streptococcus, streptococcal, group, B), A40.3 — Sepsis due to Streptococcus pneumoniae (pneumococcal), A40.8 — Other streptococcal sepsis (Streptococcus, streptococcal, specified NEC), A40.9 — Streptococcal sepsis, unspecified (Streptococcus, streptococcal), A42.7 — Actinomycotic sepsis (actinomycotic), A50.59 — Other late congenital syphilis, symptomatic (in, syphiliscongenital), A52.75 — Syphilis of kidney and ureter (syphilitic), A54.86 — Gonococcal sepsis (gonococcal), B00.7 — Disseminated herpesviral disease (herpesviral), B37.7 — Candidal sepsis (candidal), B52.0 — Plasmodium malariae malaria with nephropathy (in, Plasmodium malariae), B58.83 — Toxoplasma tubulo-interstitial nephropathy (in, toxoplasmosis), B65.9 — Schistosomiasis, unspecified (in, bilharziasis), B78.9 — Strongyloidiasis, unspecified (in, strongyloidiasis), +98 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Blood Glucose Test, Gamma-glutamyl Transferase (GGT) Test, Partial Thromboplastin Time (PTT) Test, Prothrombin Time Test and INR (PT/INR)

Contextual Map

Every relationship of A41.9 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run A41.9 with these 12 related codes in Claim Check

Hierarchy

• A00-B99 — Chapter 1: Certain Infectious and Parasitic Diseases (A00-B99) (A00-B99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A30-A49 — Other bacterial diseases[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• A48.3 — Toxic shock syndrome[Excludes1]: “sepsis NOS (A41.9)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code First instructions

• I5A — Non-ischemic myocardial injury (non-traumatic)[Code First](via A41.-): “sepsis (A41.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• N08 — Glomerular disorders in diseases classified elsewhere[Code First](via A41.-): “sepsis (A40.0-A41.9)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• N16 — Renal tubulo-interstitial disorders in diseases classified elsewhere[Code First](via A41.-): “sepsis (A40.0-A41.9)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• R65.2 — Severe sepsis[Code First]: “sepsis NOS (A41.9)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Use Additional Code instructions

• J95.02 — Infection of tracheostomy stoma[Use Additional Code](via A41.-): “sepsis (A40, A41.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• K94.02 — Colostomy infection[Use Additional Code](via A41.-): “sepsis (A40.-, A41.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• K94.12 — Enterostomy infection[Use Additional Code](via A41.-): “sepsis (A40.-, A41.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• K94.22 — Gastrostomy infection[Use Additional Code](via A41.-): “sepsis (A40.-, A41.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• K95.01 — Infection due to gastric band procedure[Use Additional Code](via A41.-): “sepsis (A40.-, A41.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• K95.81 — Infection due to other bariatric procedure[Use Additional Code](via A41.-): “sepsis (A40.-, A41.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• T80.2 — Infections following infusion, transfusion and therapeutic injection[Use Additional Code]: “sepsis (A41.9)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• INF002 — Septicemia[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)
• INF003 — Bacterial infections[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

Risk adjustment (CMS-HCC)

• HCC 2 — Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

• MCC — Major Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (MCC). Not counted when the stay groups to DRGs 974-976 (HIV with Major Related Condition).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2026
• DRG 791 — PREMATURITY WITH MAJOR PROBLEMS[MS-DRG]: “PREMATURITY WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS[MS-DRG]: “FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 870 — SEPTICEMIA OR SEVERE SEPSIS WITH MV >96 HOURS[MS-DRG]: “SEPTICEMIA OR SEVERE SEPSIS WITH MV >96 HOURS (MDC 18)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 871 — SEPTICEMIA OR SEVERE SEPSIS WITHOUT MV >96 HOURS WITH MCC[MS-DRG]: “SEPTICEMIA OR SEVERE SEPSIS WITHOUT MV >96 HOURS WITH MCC (MDC 18)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 872 — SEPTICEMIA OR SEVERE SEPSIS WITHOUT MV >96 HOURS WITHOUT MCC[MS-DRG]: “SEPTICEMIA OR SEVERE SEPSIS WITHOUT MV >96 HOURS WITHOUT MCC (MDC 18)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 974 — HIV WITH MAJOR RELATED CONDITION WITH MCC[MS-DRG]: “HIV WITH MAJOR RELATED CONDITION WITH MCC (MDC 25)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 975 — HIV WITH MAJOR RELATED CONDITION WITH CC[MS-DRG]: “HIV WITH MAJOR RELATED CONDITION WITH CC (MDC 25)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• and 1 more

MDC crossing

• MDC 15 — Newborns and Other Neonates with Conditions Originating in Perinatal Period[MDC crossing]: “Newborns and Other Neonates with Conditions Originating in Perinatal Period — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs.”— CMS MS-DRG Definitions Manual · FY2026
• MDC 18 — Infectious and Parasitic Diseases, Systemic or Unspecified Sites[MDC crossing]: “Infectious and Parasitic Diseases, Systemic or Unspecified Sites — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 1 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries

• Disorder (of), tubulo-interstitial (in), sepsis[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Glomerulonephritis, in (due to), sepsis[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pyelonephritis, in (due to), sepsis[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Sepsis (generalized) (unspecified organism)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Sepsis (generalized) (unspecified organism), cryptogenic[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Sepsis (generalized) (unspecified organism), gangrenous[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Septicemia[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes (18)

• A41 — Other sepsis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A41.0 — Sepsis due to Staphylococcus aureus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A41.01 — Sepsis due to Methicillin susceptible Staphylococcus aureus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A41.02 — Sepsis due to Methicillin resistant Staphylococcus aureus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A41.1 — Sepsis due to other specified staphylococcus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A41.2 — Sepsis due to unspecified staphylococcus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A41.3 — Sepsis due to Hemophilus influenzae[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A41.4 — Sepsis due to anaerobes[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• and 10 more

Change history

• FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Relevant guides

• Sepsis, Severe Sepsis, and Septic Shock: How Many Codes, and Which Goes First →

Real-World Coding Questions

Questions working coders have asked about this code, answered from official sources and reviewed by an editor.

• The blood culture is positive and the provider documents bacteremia. Can sepsis be coded instead? →

Common coding questions

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data

CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page

Coding guidelines Official source data

ICD-10-CM Official Guidelines for Coding and Reporting (FY2026), quoted by section Release, file and checksum · Publisher’s page

Claim edits Official source data

CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page

Inpatient payment groups Official source data

CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page

Risk adjustment Official source data

2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page

Change history and date-of-service validity Official source data

CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page

Comparisons, relationships and the contextual map MedCoder structured relationship

Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears

Summary, coding notes, decision checklist and FAQ answers MedCoder explanation

Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Nearest Codes in This Family

Official ICD-10-CM classifications closest to A41.9 in its code family, with their registry titles.

• A41.5 — Sepsis due to other Gram-negative organisms
• A41.50 — Gram-negative sepsis, unspecified
• A41.51 — Sepsis due to Escherichia coli [E. coli]
• A41.52 — Sepsis due to Pseudomonas
• A41.53 — Sepsis due to Serratia
• A41.54 — Sepsis due to Acinetobacter baumannii
• A41.59 — Other Gram-negative sepsis
• A41.8 — Other specified sepsis
• A41.81 — Sepsis due to Enterococcus
• A41.89 — Other specified sepsis

View all codes in the A41 family