2026 ICD-10-CM Diagnosis Code B39.4Histoplasmosis capsulati, unspecified

ICD-10-CM Codes›A00–B99›B35-B49›B39

ICD-10-CM B39.4
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

B39.4 is a billable ICD-10-CM diagnosis code for histoplasmosis capsulati, 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, 974 through 976. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fungal infections.

Code Identity

ICD-10-CM Code
B39.4
Billable Status
Yes — Valid for Submission
Code Describes
Histoplasmosis capsulati, unspecified
Short Description
Histoplasmosis capsulati, unspecified
Same as the full description in the CMS dataset.
Parent Code
B39
Histoplasmosis

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB35-B49Mycoses
CategoryB39Histoplasmosis
This CodeB39.4Histoplasmosis capsulati, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Classical histoplasmosis intestinal ulceration
  • Classical histoplasmosis mediastinal granuloma
  • Classical histoplasmosis mucosal ulceration
  • Classical histoplasmosis nasal ulceration
  • Classical histoplasmosis oral ulceration
  • Classical histoplasmosis penile ulceration
  • Cutaneous histoplasmosis
  • Fungal infection of liver
  • Fungal meningitis
  • Histoplasma capsulatum with endocarditis
  • Histoplasma capsulatum with pericarditis
  • Histoplasma capsulatum with retinitis
  • Histoplasma infection of central nervous system
  • Histoplasmosis liver
  • Histoplasmosis with pericarditis
  • Histoplasmosis with retinitis
  • Infection by Histoplasma capsulatum
  • Lesion of nasal mucosa
  • Meningitis caused by Histoplasma capsulatum
  • Meningitis caused by Histoplasmosis
  • Mycotic endocarditis
  • Oral mucosal fungal disease
  • Ulcer of nose

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • American histoplasmosis

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.

    • Cytomycosis(reticuloendothelial)
    • Darling's disease or histoplasmosis
    • Histoplasmosis
      • capsulati
    • Histoplasmosis
      • Darling's
    • Infection, infected, infective(opportunistic)
      • Histoplasma
        • American
    • Infection, infected, infective(opportunistic)
      • Histoplasma
        • capsulatum

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

  • Histoplasmosis

    infection resulting from exposure to the fungus histoplasma.

  • Histoplasma

    a mitosporic onygenales fungal genus causing histoplasmosis in humans and animals. its single species is histoplasma capsulatum which has two varieties: h. capsulatum var. capsulatum and h. capsulatum var. duboisii. its teleomorph is ajellomyces capsulatus.

  • Histoplasmosis

    a disease caused by the fungus histoplasma capsulatum. it primarily affects the lungs but can also occur as a disseminated disease that affects additional organs. the acute respiratory disease has symptoms similar to those of a cold or flu and it usually resolves without treatment in healthy individuals. the disseminated form is generally fatal if untreated.

Patient EducationClinical

Histoplasmosis

Histoplasmosis is an infection caused by a fungus called Histoplasma. This fungus is common in the central and eastern United States, especially around the Ohio and Mississippi River valleys. It can also be found in parts of Central and South America, Africa, Asia, and Australia.

The full article covers:

  • What is histoplasmosis?
  • How do you get histoplasmosis?
  • What are the symptoms of histoplasmosis?
  • How is histoplasmosis diagnosed?
  • What are the treatments for histoplasmosis?

Read the full article at MedlinePlus

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

Convert B39.4 to ICD-9-CMHistory

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

ICD-9-CM
115.00 Histoplasma capsulat NOS
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 B39.4Overview

Is B39.4 (Histoplasmosis) a billable code?

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

What MS-DRG does B39.4 group to?

When histoplasmosis capsulati, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 868, 869, 974, 975, 976, with relative weights from 0.7297 to 2.8860 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of B39.4?

Under the General Equivalence Mappings, histoplasmosis capsulati, unspecified converts to ICD-9-CM 115.00 (histoplasma capsulat NOS). 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.