2026 ICD-10-CM Diagnosis Code B44.1Other pulmonary aspergillosis

ICD-10-CM Codes›A00–B99›B35-B49›B44

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

B44.1 is a billable ICD-10-CM diagnosis code for other pulmonary aspergillosis. 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 and Other specified and unspecified lower respiratory disease.

Code Identity

ICD-10-CM Code
B44.1
Billable Status
Yes — Valid for Submission
Code Describes
Other pulmonary aspergillosis
Short Description
Other pulmonary aspergillosis
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 CodeB44.1Other pulmonary aspergillosis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cavitation of lung
  • Chronic cavitary pulmonary aspergillosis
  • Chronic fibrosing pulmonary aspergillosis
  • Chronic fibrosis of lung
  • Chronic pulmonary aspergillosis
  • Healthcare associated pulmonary aspergillosis
  • Inflammation of bronchus caused by Aspergillus
  • Obstructing Aspergillus tracheobronchitis
  • Pneumonia in aspergillosis
  • Pulmonary aspergillosis
  • Tracheobronchitis caused by Aspergillus

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)
      • pulmonary NEC
    • Bronchoaspergillosis

Clinical ClassificationClinical

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

CCSR INF004
Fungal infections
Default principal diagnosis: inpatient No · outpatient No
CCSR RSP016
Other specified and unspecified lower respiratory disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • 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.

  • 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.

  • Chronic Pulmonary Aspergillosis

    a spectrum of disorders associated with long-term aspergillus infection of the lung that usually occur in immunocompetent individuals with underlying respiratory disorders, and may be characterized by pulmonary fibrosis or cavitation.

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 B44.1 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 B44.1Overview

Is B44.1 (Aspergillosis) a billable code?

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

What MS-DRG does B44.1 group to?

When other pulmonary aspergillosis 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 B44.1?

Under the General Equivalence Mappings, other pulmonary aspergillosis 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.