2027 ICD-10-CM Diagnosis Code A40.8Other streptococcal sepsis

ICD-10-CM Codes›A00–B99›A30-A49›A40

ICD-10-CM A40.8
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

A40.8 is a billable ICD-10-CM diagnosis code for other streptococcal sepsis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 870 through 872. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 46 closely related codes. Coders also document this condition as sepsis caused by Streptococcus suis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections and Septicemia.

For Medicare Advantage risk adjustment, A40.8 maps to CMS-HCC Category 2 (Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock) under the V28 model, adding a risk factor of about 0.500 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
A40.8
Billable Status
Yes — Valid for Submission
Code Describes
Other streptococcal sepsis
Short Description
Other streptococcal sepsis
Same as the full description in the CMS dataset.
Parent Code
Streptococcal sepsis

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA30-A49Other bacterial diseases
CategoryA40Streptococcal sepsis
This CodeA40.8Other streptococcal sepsis

Medicare Risk Adjustment (HCC)Billing

A40.8 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 2— Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock
Payment HCC · PY 2027 one of 52 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.500
community, non-dual, aged · ranges 0.447–0.780 across segments
Hierarchy
Top of its hierarchy
HCC 2 is not superseded by any other condition category
Prior Model (CMS-HCC V24)
HCC 2
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 2 · ESRD (V21): HCC 2 · ESRD (V24): HCC 2
ESRD V21 weights: 0.081 dialysis, 0.274–0.428 functioning graft · ESRD V24 weights: 0.087 dialysis, 0.270–0.532 functioning graft
Part D (RxHCC)
Not mapped
A40.8 does not risk-adjust in the RxHCC prescription drug model

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Sepsis caused by Streptococcus suis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A40.8: its own notes plus those printed at A40 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From A40 Streptococcal sepsis applies to 5 codes

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Code First

The underlying condition named in the note is sequenced before this code.

From A40 Streptococcal sepsis applies to 5 codes
  • if applicable, postprocedural sepsis (T81.44-)
  • sepsis due to central venous catheter (T80.211-)
  • streptococcal sepsis during labor (O75.3)
  • streptococcal sepsis following abortion or ectopic or molar pregnancy (O03.37, O03.87, O04.87, O07.37, O08.82)
  • streptococcal sepsis following immunization (T88.0-)
  • streptococcal sepsis following infusion, transfusion or therapeutic injection (T80.22-, T80.29-)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name A40.8, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming A40.8: they are not reported together with it, unless the two conditions are unrelated.

  • A41 Other sepsis
    streptococcal sepsis (A40.-) names A40.-, which includes this code

Code First 2

These codes say to code first a condition named in the note, and A40.8 is one of the conditions named.

  • N08 Glomerular disorders in diseases classified elsewhere
    sepsis (A40.0-A41.9) names A40.0-A41.9, which includes this code
  • N16 Renal tubulo-interstitial disorders in diseases classified elsewhere
    sepsis (A40.0-A41.9) names A40.0-A41.9, which includes this code

Use Additional Code 6

These codes say to use an additional code from the note, and A40.8 is one of the codes named.

  • J95.02 Infection of tracheostomy stoma
    sepsis (A40, A41.-) names A40, which includes this code
  • K94.02 Colostomy infection
    sepsis (A40.-, A41.-) names A40.-, which includes this code
  • K94.12 Enterostomy infection
    sepsis (A40.-, A41.-) names A40.-, which includes this code
  • K94.22 Gastrostomy infection
    sepsis (A40.-, A41.-) names A40.-, which includes this code
  • K95.01 Infection due to gastric band procedure
    sepsis (A40.-, A41.-) names A40.-, which includes this code
  • K95.81 Infection due to other bariatric procedure
    sepsis (A40.-, A41.-) names A40.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INF003
Bacterial infections
Default principal diagnosis: inpatient No · outpatient No
CCSR INF002
Septicemia
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Sepsis

Sepsis is your body's overactive and extreme response to an infection. Sepsis is a life-threatening medical emergency. Without quick treatment, it can lead to tissue damage, organ failure, and even death.

The full article covers:

  • What is sepsis?
  • What causes sepsis?
  • Who is more likely to develop sepsis?
  • What are the symptoms of sepsis?
  • What other problems can sepsis cause?
  • How is sepsis diagnosed?
  • What are the treatments for sepsis?
  • Can sepsis be prevented?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert A40.8 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
038.0 Streptococcal septicemia
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.
ICD-9-CM
995.91 Sepsis
ApproximateCombination The match is approximate, and more than one code can be needed to describe the source diagnosis. Confirm with contextual judgment.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About A40.8Overview

What is the ICD-10 code for other streptococcal sepsis?

The ICD-10-CM code for other streptococcal sepsis is A40.8 (sometimes written as A408). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is A40.8 (Streptococcal sepsis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other streptococcal sepsis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does A40.8 group to?

When other streptococcal sepsis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 872, 871, 870, with relative weights from 1.0066 to 6.9432 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A40.8 a CC or MCC?

CMS lists A40.8 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 46 closely related codes in its exclusion list.

Can A40.8 be reported with O85?

Not as a rule. The Excludes1 note at A40, which applies to A40.8, lists "puerperal sepsis (O85)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What HCC is A40.8?

A40.8 (other streptococcal sepsis) maps to CMS-HCC Category 2 (Septicemia, Sepsis, Systemic Inflammatory Response Syndrome/Shock), commonly written as HCC 2, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 2 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.

Does A40.8 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, A40.8 adds a risk adjustment factor of about 0.500 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.447 to 0.780 depending on the payment segment). HCC 2 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 2 category page.