B44 ICD-10-CM Code: Aspergillosis

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for B44 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 B44 itself; “inherited from” names the category or block whose note applies here.

This page already reflects the FY2027 tabular notes taking effect October 1, 2026.

Coder workflow for B44

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

Before you code B44

1. B44 is not reportable as written. Select the more specific code beneath it that the documentation supports. Codes are reported to the highest level of specificity the classification provides (Guidelines I.B.2).

   ReviewB44.0, B44.1, B44.2, B44.7, B44.8, B44.9

   See the relationships section · Guide: How to choose an ICD-10-CM code →

Choose the right path

1. Does the documentation support one of the more specific codes beneath B44?
   Yes → Select that code and continue the checks below on its own page.
   No → B44 cannot be reported as written; query for the specificity its subcategory needs.

   ReviewB44.0, B44.1, B44.2, B44.7, B44.8, B44.9

Consider B44. Then review the Code Also note, and 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).

Official instructions as workflow

• Excludes2 — not part of B44(2 notes)

  Coding workflow: The conditions named in this note are not included in B44. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareJ67, C84.0

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

• Code Also — related condition(6 notes)

  Coding workflow: Review the related condition when both are documented and the instruction applies. A Code Also note does not fix sequencing; the order follows the circumstances of the encounter.

  ReviewJ4B, J32

  See the official tabular notes · Guidelines I.A.17

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 B44 with…

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

The codes most likely to be picked instead of B44 — 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.

• J67— 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 hypersensitivity pneumonitis due to organic dust adds J67; it is not part of this code and both may be reported when both are documented.

  Full comparison: B44 vs J67 →

• C84.0— 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 mycosis fungoides adds C84.0; it is not part of this code and both may be reported when both are documented.

  Full comparison: B44 vs C84.0 →

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

• Not billable as written — a more specific code is required: B44.0, B44.1, B44.2, B44.7, B44.81.

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 B44 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 Excludes2 note: J82 — Pulmonary eosinophilia, not elsewhere classified.

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

Referenced by 1 Code First instruction: M01 — Direct infections of joint in infectious and parasitic 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.

Referenced by 1 Code Also instruction: J4B — Pulmonary mycetoma.

These codes suggest coding this condition alongside when both are present.

Contextual Map

Every relationship of B44 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 B44 with these 6 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
• B35-B49 — Mycoses[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Excludes2

• C84.0 — Mycosis fungoides[Excludes2]: “mycosis fungoides (C84.0-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• J67 — Hypersensitivity pneumonitis due to organic dust[Excludes2]: “hypersensitivity pneumonitis due to organic dust (J67.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Code Also

• J32 — Chronic sinusitis[Code Also]: “sinus aspergilloma (J32.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• J4B — Pulmonary mycetoma[Code Also]: “pulmonary aspergilloma (J4B)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Excludes2 notes

• J82 — Pulmonary eosinophilia, not elsewhere classified[Excludes2]: “pulmonary eosinophilia due to aspergillosis (B44.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code First instructions

• M01 — Direct infections of joint in infectious and parasitic diseases classified elsewhere[Code First]: “mycoses (B35-B49)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code Also instructions

• J4B — Pulmonary mycetoma[Code Also]: “aspergillosis (B44.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Nearest codes

• B44.0 — Invasive pulmonary aspergillosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• B44.1 — Other pulmonary aspergillosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• B44.2 — Tonsillar aspergillosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• B44.7 — Disseminated aspergillosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• B44.8 — Other forms of aspergillosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• B44.81 — Allergic bronchopulmonary aspergillosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• B44.89 — Other forms of aspergillosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• B44.9 — Aspergillosis, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Change history (8)

• FY2027 — Code Also note will be added[Change history]— CMS release files (code change ledger) · icd10cm-fy2027
• and 7 more

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

Claim edits Official source data

CMS Definitions of Medicare Code Edits — v43.1 (April 2026) 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 B44 in its code family, with their registry titles.

• B44.0 — Invasive pulmonary aspergillosis
• B44.1 — Other pulmonary aspergillosis
• B44.2 — Tonsillar aspergillosis
• B44.7 — Disseminated aspergillosis
• B44.8 — Other forms of aspergillosis
• B44.81 — Allergic bronchopulmonary aspergillosis
• B44.89 — Other forms of aspergillosis
• B44.9 — Aspergillosis, unspecified