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A75.3 ICD-10-CM Code: Typhus fever due to Rickettsia tsutsugamushi

Compare with another code for A75.3Check this code on a claim

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
3 inclusion terms · 1 Excludes1

Billable · FY2027A valid, specific ICD-10-CM code, reportable for dates of service in FY2027.

What you need to know

Source: CMS/NCHS Official ICD-10-CM tabular notes, quoted. From the CMS/NCHS tabular list for the release in force. A note the category or block publishes applies to this code too, and is marked with where it comes from.

Excludes1from A75Not reported with this code unless documented as unrelated
  • rickettsiosis due to Ehrlichia sennetsu (A79.81)
IncludesWhat this code covers
  • Scrub (mite-borne) typhus
  • Tsutsugamushi fever
  • Typhus fever due to Orientia Tsutsugamushi (scrub typhus)

Where it sits Source: CMS/NCHS

Under:Chapter 1: Certain Infectious and Parasitic DiseasesA75-A79 RickettsiosesA75 Typhus fever

Most relevant related codes MedCoder-derived

Read off the official notes above and this code’s own position in the tabular list. Which to report is a documentation question; Compare shows the two side by side.

CompareCheck ClaimView Related Codes

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v44, Appendix B.

  • MS-DRG 867 — OTHER INFECTIOUS AND PARASITIC DISEASES DIAGNOSES WITH MCC (MDC 18)
  • MS-DRG 868 — OTHER INFECTIOUS AND PARASITIC DISEASES DIAGNOSES WITH CC (MDC 18)
  • MS-DRG 869 — OTHER INFECTIOUS AND PARASITIC DISEASES DIAGNOSES WITHOUT CC/MCC (MDC 18)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for A75.3 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Trace:FY2027 changesChange historyRelease, file and checksum

Notes without a marker are published on A75.3 itself; “inherited from” names the category or block whose note applies here.

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Scrub (mite-borne) typhus
  • Tsutsugamushi fever
  • Typhus fever due to Orientia Tsutsugamushi (scrub typhus)

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from A75

Coder workflow for A75.3

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

Before you code A75.3

  1. A75.3’s title joins a condition with an associated condition or complication. Confirm each component is documented. Where the classification presumes the link through the “with” convention, only a provider statement that the conditions are unrelated defeats it. A combination code is assigned only when it fully identifies the documented conditions; a required second code for the stage, type or manifestation is still reported when the notes ask for it (Guidelines I.B.9, I.A.15).

    Guide: Combination codes →

  2. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with A75.3. 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 documentation support a condition named in A75.3’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.

    ReviewA79.81

Consider A75.3. 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 associated condition or complication
Whether the associated condition the title names is documented; the “with” convention presumes some links, and a provider statement that the conditions are unrelated defeats it (Guidelines I.A.15).

Official instructions as workflow

  • Excludes1 — check before selecting A75.3(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with A75.3: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareA79.81

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

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Both the condition A75.3 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewA79.81

Documentation: Only one of the components this code’s title joins is documented.

Coding question: Is A75.3 supported?

Path: Review the code for the documented component on its own.

Reason: A combination code is assigned only when it fully identifies the documented conditions; otherwise the documented component takes its own code (Guidelines I.B.9).

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.

Don’t confuse A75.3 with…

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

The codes most likely to be picked instead of A75.3 — 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.

  • A79.81— 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 rickettsiosis due to Ehrlichia sennetsu moves the case to A79.81; the two are not reported together unless documented as unrelated.

    Full comparison: A75.3 vs A79.81 →

  • A75.9— Specificity relationship (Review)

    Overlapping diagnoses in the same category.

    Overlapping codes in the same category — the documentation decides which is the more specific fit.

    What moves you there: A record that documents no more than “Typhus fever, unspecified” takes A75.9; specificity in the record moves it back here.

    Full comparison: A75.3 vs A75.9 →

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.

Coding context

Guidelines, coding notes, decision aids, relationships (with MS-DRG and CCSR classification), hierarchy, HCC, coverage and the context map: what a coder reaches for after the core. Each section names whether it is official source data, a MedCoder-derived relationship or MedCoder editorial.

Code Overview

Typhus fever due to Rickettsia tsutsugamushi is a billable ICD-10-CM diagnosis code (A75.3).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Verify Before Coding

  • CC as a secondary diagnosis (FY2027). 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-derived relationships — computed from published CMS and AHRQ datasets

Other codes that name A75.3 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 Code First instruction: I41 — Myocarditis in diseases classified elsewhere.

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.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: CC — 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 56 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 3 MS-DRGs: DRG 867 (MDC 18), DRG 868 (MDC 18), DRG 869 (MDC 18).

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

Clinical classification (AHRQ CCSR):INF009 — Parasitic, other specified and unspecified infections (default).

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 CC — 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.

A68.1 — Tick-borne relapsing fever, A68.9 — Relapsing fever, unspecified, A69.20 — Lyme disease, unspecified, A69.21 — Meningitis due to Lyme disease, A69.22 — Other neurologic disorders in Lyme disease, A69.23 — Arthritis due to Lyme disease, A69.29 — Other conditions associated with Lyme disease, A75.0 — Epidemic louse-borne typhus fever due to Rickettsia prowazekii, A75.1 — Recrudescent typhus [Brill's disease], A75.2 — Typhus fever due to Rickettsia typhi, A75.9 — Typhus fever, unspecified, A77.0 — Spotted fever due to Rickettsia rickettsii, A77.1 — Spotted fever due to Rickettsia conorii, A77.2 — Spotted fever due to Rickettsia siberica, A77.3 — Spotted fever due to Rickettsia australis, A77.40 — Ehrlichiosis, unspecified, A77.41 — Ehrlichiosis chaffeensis [E. chaffeensis], A77.49 — Other ehrlichiosis, A77.8 — Other spotted fevers, A77.9 — Spotted fever, unspecified, +35 more

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Parasitic, other specified and unspecified infections).

A69.20 — Lyme disease, unspecified, A69.21 — Meningitis due to Lyme disease, A69.22 — Other neurologic disorders in Lyme disease, A69.23 — Arthritis due to Lyme disease, A69.29 — Other conditions associated with Lyme disease, A69.8 — Other specified spirochetal infections, A69.9 — Spirochetal infection, unspecified, A75.0 — Epidemic louse-borne typhus fever due to Rickettsia prowazekii, A75.1 — Recrudescent typhus [Brill's disease], A75.2 — Typhus fever due to Rickettsia typhi, A75.9 — Typhus fever, unspecified, A77.0 — Spotted fever due to Rickettsia rickettsii, A77.1 — Spotted fever due to Rickettsia conorii, A77.2 — Spotted fever due to Rickettsia siberica, A77.3 — Spotted fever due to Rickettsia australis, A77.40 — Ehrlichiosis, unspecified, A77.41 — Ehrlichiosis chaffeensis [E. chaffeensis], A77.49 — Other ehrlichiosis, A77.8 — Other spotted fevers, A77.9 — Spotted fever, unspecified, +235 more

Same Index main term, other category

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

A28.1 — Cat-scratch disease (cat-scratch), A38.9 — Scarlet fever, uncomplicated (scarlet), A39.0 — Meningococcal meningitis (petechial), A44.0 — Systemic bartonellosis (Oroya), A48.2 — Nonpneumonic Legionnaires' disease [Pontiac fever] (Pontiac), A48.4 — Brazilian purpuric fever (Brazilian purpuric), A68.0 — Louse-borne relapsing fever (relapsing, louse-borne), A68.1 — Tick-borne relapsing fever (mianeh), A68.9 — Relapsing fever, unspecified (relapsing), A70 — Chlamydia psittaci infections (parrot), A77.0 — Spotted fever due to Rickettsia rickettsii (Bullis), A77.1 — Spotted fever due to Rickettsia conorii (Kenya), A77.2 — Spotted fever due to Rickettsia siberica (Siberian tick), A77.3 — Spotted fever due to Rickettsia australis (Queensland), A77.40 — Ehrlichiosis, unspecified (spotted, Ehrlichiosis), A77.41 — Ehrlichiosis chaffeensis [E. chaffeensis] (spotted, Ehrlichiosis, due to, E. chaffeensis), A77.49 — Other ehrlichiosis (spotted, Ehrlichiosis, due to, specified organism NEC), A77.8 — Other spotted fevers (African tick bite), A77.9 — Spotted fever, unspecified (spotted), A78 — Q fever (Q), +107 more

Contextual Map

Every relationship of A75.3 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 A75.3 with this related code in Claim Check

Hierarchy

Referenced by Code First instructions

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

  • 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 · FY2027

Index entries (19)

  • Disease, diseased, akamushi (scrub typhus)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Disease, diseased, island (scrub typhus)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Disease, diseased, Kedani (scrub typhus)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Disease, diseased, shimamushi (scrub typhus)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Disease, diseased, tsutsugamushi[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor), Japanese river[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor), kedani[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor), Sumatran mite[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2027
  • and 11 more

Nearest codes

Change history

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

Reference

Index terms and tables, published questions and FAQ, every source behind this page with its release and checksum, the date-of-service check and the complete change history.

Indexed Clinical Terms (19)

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.

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 FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v44.0 (October 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 — v44 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-derived relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder editorial 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.

Current data releases:ICD-10-CM FY2027 · ICD-10-PCS FY2027 · HCPCS October 2026 · MS-DRG v44 · Medicare Code Editor v44.0 · NCCI PTP Q4 2026 · MUE Q4 2026 · NCD code lists 2026-01 · LCD export September 28, 2026 · All releases and sources

Labels on this page: Official source data · MedCoder-derived relationship · MedCoder editorial explanation. How to read the labels · All data sources and release dates · CMS coding rules

Cite this page

Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.

MedCoder.ai. "A75.3 — Typhus fever due to Rickettsia tsutsugamushi." ICD-10-CM FY2027. https://medcoder.ai/icd10/code/a75.3-typhus-fever-due-to-rickettsia-tsutsugamushi

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Typhus fever due to Rickettsia tsutsugamushi

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027, and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to A75.3 in its code family, with their registry titles.

View all codes in the A75 family