2026 ICD-10-CM Diagnosis Code B44.9Aspergillosis, unspecified

ICD-10-CM Codes›A00–B99›B35-B49›B44

ICD-10-CM B44.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

B44.9 is a billable ICD-10-CM diagnosis code for aspergillosis, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 867 through 869. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fungal infections.

Code Identity

ICD-10-CM Code
B44.9
Billable Status
Yes — Valid for Submission
Code Describes
Aspergillosis, unspecified
Short Description
Aspergillosis, unspecified
Same as the full description in the CMS dataset.
Parent Code
B44
Aspergillosis

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB35-B49Mycoses
CategoryB44Aspergillosis
This CodeB44.9Aspergillosis, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Aspergilloma
  • Aspergillosis
  • Aspergillosis co-occurrent with human immunodeficiency virus infection
  • Chronic mycotic otitis externa
  • Chronic otitis externa due to aspergillosis
  • Infection by Aspergillus clavatus
  • Infection by Aspergillus flavus
  • Infection by Aspergillus fumigatus
  • Infection by Aspergillus nidulans
  • Infection by Aspergillus niger
  • Infection caused by Aspergillus awamori
  • Infection caused by Aspergillus bouffardii
  • Infection caused by Aspergillus caesiellus
  • Infection caused by Aspergillus candidus
  • Infection caused by Aspergillus carneus
  • Infection caused by Aspergillus chevalieri
  • Infection caused by Aspergillus clavato-nanica
  • Infection caused by Aspergillus conicus
  • Infection caused by Aspergillus deflectus
  • Infection caused by Aspergillus flavipes
  • Infection caused by Aspergillus glaucus
  • Infection caused by Aspergillus janus
  • Infection caused by Aspergillus maydis
  • Infection caused by Aspergillus montevidensis
  • Infection caused by Aspergillus niveus
  • Infection caused by Aspergillus notatum
  • Infection caused by Aspergillus ochraceus
  • Infection caused by Aspergillus oryzae
  • Infection caused by Aspergillus parasiticus
  • Infection caused by Aspergillus penicillioides
  • Infection caused by Aspergillus phialiseptus
  • Infection caused by Aspergillus repens
  • Infection caused by Aspergillus restrictus
  • Infection caused by Aspergillus rugulosus
  • Infection caused by Aspergillus sclerotiorum
  • Infection caused by Aspergillus sulfureus
  • Infection caused by Aspergillus sydowi
  • Infection caused by Aspergillus taumanii
  • Infection caused by Aspergillus terreus
  • Infection caused by Aspergillus terricola
  • Infection caused by Aspergillus unguis
  • Infection caused by Aspergillus ustus
  • Infection caused by Aspergillus versicolor
  • Infection caused by Aspergillus wentii
  • Infection caused by Neosartorya fischeri
  • Invasive aspergillosis
  • Neonatal infection caused by Aspergillus
  • Pulmonary aspergillosis

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Aspergillosis(with pneumonia)
    • Pneumonia(acute) (double) (migratory) (purulent) (septic) (unresolved)
      • in (due to)
        • aspergillosis

Clinical ClassificationClinical

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

CCSR INF004
Fungal infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Aspergillosis

    infections with fungi of the genus aspergillus.

  • Aspergillosis, Allergic Bronchopulmonary

    hypersensitivity reaction (allergic reaction) to fungus aspergillus in an individual with long-standing bronchial asthma. it is characterized by pulmonary infiltrates, eosinophilia, elevated serum immunoglobulin e, and skin reactivity to aspergillus antigen.

  • Invasive Pulmonary Aspergillosis

    lung infections with the invasive forms of aspergillus, usually after surgery, transplantation, prolonged neutropenia or treatment with high-doses of corticosteroids. invasive pulmonary aspergillosis can progress to chronic necrotizing pulmonary aspergillosis or hematogenous spread to other organs.

  • Neuroaspergillosis

    infections of the nervous system caused by fungi of the genus aspergillus, most commonly aspergillus fumigatus. aspergillus infections may occur in immunocompetent hosts, but are more prevalent in individuals with immunologic deficiency syndromes. the organism may spread to the nervous system from focal infections in the lung, mastoid region, sinuses, inner ear, bones, eyes, gastrointestinal tract, and heart. sinus infections may be locally invasive and enter the intracranial compartment, producing meningitis, fungal; cranial neuropathies; and abscesses in the frontal lobes of the brain. (from joynt, clinical neurology, 1998, ch 27, pp62-3)

  • Pulmonary Aspergillosis

    infections of the respiratory tract with fungi of the genus aspergillus.

  • Aspergillus

    a genus of mitosporic fungi containing about 100 species and eleven different teleomorphs in the family trichocomaceae.

Patient EducationClinical

Aspergillosis

Aspergillosis is a disease caused by a fungus (or mold) called Aspergillus. The fungus is very common in both indoors and outdoors. Most people breathe in the spores of the fungus every day without being affected. But some people get the disease. It usually occurs in people with lung diseases or weakened immune systems.

Read the full article at MedlinePlus

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

Convert B44.9 to ICD-9-CMHistory

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

ICD-9-CM
117.3 Aspergillosis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About B44.9Overview

Is B44.9 (Aspergillosis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report aspergillosis, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does B44.9 group to?

When aspergillosis, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 868, 869, with relative weights from 0.7297 to 2.0932 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of B44.9?

Under the General Equivalence Mappings, aspergillosis, unspecified converts to ICD-9-CM 117.3 (aspergillosis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.