A31.0 ICD-10-CM Code: Pulmonary mycobacterial infection

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for A31.0 in the official ICD-10-CM tabular list, quoted as published.

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

Notes without a marker are published on A31.0 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for A31.0

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

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).

Official instructions as workflow

• Excludes2 — not part of A31.0(2 notes)

  Coding workflow: The conditions named in this note are not included in A31.0. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareA30

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

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.

Indexed Clinical Terms (10)

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.

• Battey Mycobacterium infection
• Disease, diseased, Battey
• Disease, diseased, photochromogenic (acid-fast bacilli) (pulmonary)
• Infection, infected, infective (opportunistic), lung, atypical Mycobacterium
• Mycobacterium, mycobacterial (infection), atypical, pulmonary
• Mycobacterium, mycobacterial (infection), avium (intracellulare complex)
• Mycobacterium, mycobacterial (infection), Battey
• Mycobacterium, mycobacterial (infection), intracellulare (Battey bacillus)
• Mycobacterium, mycobacterial (infection), kansasii (yellow bacillus)
• Mycobacterium, mycobacterial (infection), pulmonary (atypical)

Don’t confuse A31.0 with…

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

The codes most likely to be picked instead of A31.0 — 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.

• A31.9— 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 “Mycobacterial infection, unspecified” takes A31.9; specificity in the record moves it back here.

  Full comparison: A31.0 vs A31.9 →

• A30— 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 leprosy adds A30; it is not part of this code and both may be reported when both are documented.

  Full comparison: A31.0 vs A30 →

• A15— 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 tuberculosis adds A15; it is not part of this code and both may be reported when both are documented.

  Full comparison: A31.0 vs A15 →

• A19— 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 tuberculosis adds A19; it is not part of this code and both may be reported when both are documented.

  Full comparison: A31.0 vs A19 →

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.

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 structured relationships — computed from published CMS and AHRQ datasets

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 122 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 3 MS-DRGs: DRG 177 (MDC 04), DRG 178 (MDC 04), DRG 179 (MDC 04).

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

Clinical classification (AHRQ CCSR):RSP002 — Pneumonia (except that caused by tuberculosis) (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.

A15.4 — Tuberculosis of intrathoracic lymph nodes, A15.5 — Tuberculosis of larynx, trachea and bronchus, A15.6 — Tuberculous pleurisy, A15.8 — Other respiratory tuberculosis, A15.9 — Respiratory tuberculosis unspecified, A17.9 — Tuberculosis of nervous system, unspecified, A18.82 — Tuberculosis of other endocrine glands, A18.84 — Tuberculosis of heart, A18.89 — Tuberculosis of other sites, A22.1 — Pulmonary anthrax, A31.2 — Disseminated mycobacterium avium-intracellulare complex (DMAC), A31.8 — Other mycobacterial infections, A31.9 — Mycobacterial infection, unspecified, A37.01 — Whooping cough due to Bordetella pertussis with pneumonia, A37.11 — Whooping cough due to Bordetella parapertussis with pneumonia, A37.81 — Whooping cough due to other Bordetella species with pneumonia, A37.91 — Whooping cough, unspecified species with pneumonia, A48.1 — Legionnaires' disease, A49.3 — Mycoplasma infection, unspecified site, A49.8 — Other bacterial infections of unspecified site, +101 more

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Opportunistic Infections) for risk-adjusted payment.

A07.2 — Cryptosporidiosis, A31.2 — Disseminated mycobacterium avium-intracellulare complex (DMAC), B25.0 — Cytomegaloviral pneumonitis, B25.1 — Cytomegaloviral hepatitis, B25.2 — Cytomegaloviral pancreatitis, B25.8 — Other cytomegaloviral diseases, B25.9 — Cytomegaloviral disease, unspecified, B37.1 — Pulmonary candidiasis, B37.7 — Candidal sepsis, B37.81 — Candidal esophagitis, B44.0 — Invasive pulmonary aspergillosis, B44.1 — Other pulmonary aspergillosis, B44.2 — Tonsillar aspergillosis, B44.7 — Disseminated aspergillosis, B44.89 — Other forms of aspergillosis, B44.9 — Aspergillosis, unspecified, B45.0 — Pulmonary cryptococcosis, B45.1 — Cerebral cryptococcosis, B45.2 — Cutaneous cryptococcosis, B45.3 — Osseous cryptococcosis, +16 more

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Pneumonia (except that caused by tuberculosis), Bacterial infections).

A01.03 — Typhoid pneumonia, A02.22 — Salmonella pneumonia, A20.2 — Pneumonic plague, A21.2 — Pulmonary tularemia, A22.1 — Pulmonary anthrax, A37.01 — Whooping cough due to Bordetella pertussis with pneumonia, A37.11 — Whooping cough due to Bordetella parapertussis with pneumonia, A37.81 — Whooping cough due to other Bordetella species with pneumonia, A37.91 — Whooping cough, unspecified species with pneumonia, A43.0 — Pulmonary nocardiosis, A48.1 — Legionnaires' disease, A50.04 — Early congenital syphilitic pneumonia, A52.72 — Syphilis of lung and bronchus, A54.84 — Gonococcal pneumonia, B01.2 — Varicella pneumonia, B05.2 — Measles complicated by pneumonia, B06.81 — Rubella pneumonia, B25.0 — Cytomegaloviral pneumonitis, B37.1 — Pulmonary candidiasis, B38.0 — Acute pulmonary coccidioidomycosis, +418 more

Same Index main term, other category

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

A30.9 — Leprosy, unspecified

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.

HIV Screening Test

Contextual Map

Every relationship of A31.0 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.

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

Clinical classification (CCSR)

• RSP002 — Pneumonia (except that caused by tuberculosis)[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 6 — Opportunistic Infections [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

• CC — Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (CC).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2027
• DRG 177 — RESPIRATORY INFECTIONS AND INFLAMMATIONS WITH MCC[MS-DRG]: “RESPIRATORY INFECTIONS AND INFLAMMATIONS WITH MCC (MDC 04)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
• DRG 178 — RESPIRATORY INFECTIONS AND INFLAMMATIONS WITH CC[MS-DRG]: “RESPIRATORY INFECTIONS AND INFLAMMATIONS WITH CC (MDC 04)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
• DRG 179 — RESPIRATORY INFECTIONS AND INFLAMMATIONS WITHOUT CC/MCC[MS-DRG]: “RESPIRATORY INFECTIONS AND INFLAMMATIONS WITHOUT CC/MCC (MDC 04)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027

MDC crossing

• MDC 04 — Diseases and Disorders of the Respiratory System[MDC crossing]: “Diseases and Disorders of the Respiratory System — 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. 4,000 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Index entries (10)

• Battey Mycobacterium infection[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Disease, diseased, Battey[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Disease, diseased, photochromogenic (acid-fast bacilli) (pulmonary)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Infection, infected, infective (opportunistic), lung, atypical Mycobacterium[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Mycobacterium, mycobacterial (infection), atypical, pulmonary[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Mycobacterium, mycobacterial (infection), avium (intracellulare complex)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Mycobacterium, mycobacterial (infection), Battey[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Mycobacterium, mycobacterial (infection), intracellulare (Battey bacillus)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• and 2 more

Nearest codes

• A31 — Infection due to other mycobacteria[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A31.1 — Cutaneous mycobacterial infection[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A31.2 — Disseminated mycobacterium avium-intracellulare complex (DMAC)[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A31.8 — Other mycobacterial infections[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• A31.9 — Mycobacterial infection, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

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 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

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 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 A31.0 in its code family, with their registry titles.

• A31 — Infection due to other mycobacteria
• A31.1 — Cutaneous mycobacterial infection
• A31.2 — Disseminated mycobacterium avium-intracellulare complex (DMAC)
• A31.8 — Other mycobacterial infections
• A31.9 — Mycobacterial infection, unspecified

View all codes in the A31 family