Skip to main content

A01.01 ICD-10-CM Code: Typhoid meningitis

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

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 v43, 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.

Code Overview

Typhoid meningitis is a billable ICD-10-CM diagnosis code (A01.01).

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

Indexed Clinical Terms (4)

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.

Verify Before Coding

  • CC 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 A01.01 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 6 Excludes2 notes: P35 — Congenital viral diseases (via A01.-), P35-P39 — Infections specific to the perinatal period (P35-P39) (via A01.-), P36 — Bacterial sepsis of newborn (via A01.-), P37 — Other congenital infectious and parasitic diseases (via A01.-), P38 — Omphalitis of newborn (via A01.-), P39 — Other infections specific to the perinatal period (via A01.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 1 Code First instruction: M49 — Spondylopathies in diseases classified elsewhere (via A01.-).

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 (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 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 11 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):NVS001 — Meningitis (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 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.

A01.00 — Typhoid fever, unspecified, A01.02 — Typhoid fever with heart involvement, A01.03 — Typhoid pneumonia, A01.04 — Typhoid arthritis, A01.05 — Typhoid osteomyelitis, A01.09 — Typhoid fever with other complications, A01.1 — Paratyphoid fever A, A01.2 — Paratyphoid fever B, A01.3 — Paratyphoid fever C, A01.4 — Paratyphoid fever, unspecified

Same clinical category (CCSR)

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

A02.21 — Salmonella meningitis, A17.0 — Tuberculous meningitis, A17.1 — Meningeal tuberculoma, A20.3 — Plague meningitis, A27.81 — Aseptic meningitis in leptospirosis, A32.11 — Listerial meningitis, A39.0 — Meningococcal meningitis, A42.81 — Actinomycotic meningitis, A50.41 — Late congenital syphilitic meningitis, A51.41 — Secondary syphilitic meningitis, A52.13 — Late syphilitic meningitis, A54.81 — Gonococcal meningitis, A69.21 — Meningitis due to Lyme disease, A87.0 — Enteroviral meningitis, A87.1 — Adenoviral meningitis, A87.2 — Lymphocytic choriomeningitis, A87.8 — Other viral meningitis, A87.9 — Viral meningitis, unspecified, B00.3 — Herpesviral meningitis, B01.0 — Varicella meningitis, +413 more

Same Index main term, other category

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

A02.21 — Salmonella meningitis (Salmonella), A02.8 — Other specified salmonella infections (swine), A17.0 — Tuberculous meningitis (caseous), A20.3 — Plague meningitis (Yersinia pestis), A22.8 — Other forms of anthrax (in, anthrax), A23.1 — Brucellosis due to Brucella abortus (abortus), A23.9 — Brucellosis, unspecified (Malta), A25.0 — Spirillosis (spirillary), A25.1 — Streptobacillosis (Haverhill), A25.9 — Rat-bite fever, unspecified (rat-bite), A27.0 — Leptospirosis icterohemorrhagica (icterohemorrhagic), A27.81 — Aseptic meningitis in leptospirosis (leptospiral), A27.89 — Other forms of leptospirosis (pretibial), A27.9 — Leptospirosis, unspecified (mud), A28.1 — Cat-scratch disease (cat-scratch), A32.11 — Listerial meningitis (in, Listeria monocytogenes), A37.90 — Whooping cough, unspecified species without pneumonia (in, whooping cough), A38.9 — Scarlet fever, uncomplicated (scarlet), A39.0 — Meningococcal meningitis (petechial), A42.81 — Actinomycotic meningitis (actinomycotic), +150 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.

Iron Panel, Partial Thromboplastin Time (PTT) Test, Prothrombin Time Test and INR (PT/INR)

Contextual Map

Every relationship of A01.01 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 A01.01 with these 7 related codes in Claim Check

Hierarchy

Referenced by Excludes2 notes

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 · FY2026

Index entries

  • Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor), typhoid (abortive) (hemorrhagic) (intermittent) (malignant), complicated by, meningitis[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Meningitis (basal) (basic) (brain) (cerebral) (cervical) (congestive) (diffuse) (hemorrhagic) (infantile) (membranous) (metastatic) (nonspecific) (pontine) (progressive) (simple) (spinal) (subacute) (sympathetic) (toxic), in (due to), typhoid fever[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Meningitis (basal) (basic) (brain) (cerebral) (cervical) (congestive) (diffuse) (hemorrhagic) (infantile) (membranous) (metastatic) (nonspecific) (pontine) (progressive) (simple) (spinal) (subacute) (sympathetic) (toxic), typhoid[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Typhoid (abortive) (ambulant) (any site) (clinical) (fever) (hemorrhagic) (infection) (intermittent) (malignant) (rheumatic) (Widal negative), meningitis[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes (12)

Change history

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

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
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
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 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

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Typhoid meningitis

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), 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 A01.01 in its code family, with their registry titles.

View all codes in the A01 family