Histoplasmosis (B39) ICD-10-CM
The B39 code range covers histoplasmosis with 8 ICD-10-CM diagnosis codes. 7 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Code First
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
- associated AIDS B20
Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
Codes in the B39 Range 8 codes · 7 billable
- B39 HistoplasmosisNon-billable
- B39.0 Acute pulmonary histoplasmosis capsulati
- B39.1 Chronic pulmonary histoplasmosis capsulati
- B39.2 Pulmonary histoplasmosis capsulati, unspecified
- B39.3 Disseminated histoplasmosis capsulati
- B39.4 Histoplasmosis capsulati, unspecified
- B39.5 Histoplasmosis duboisii
- B39.9 Histoplasmosis, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the B39 range.
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
Infection resulting from exposure to the fungus HISTOPLASMA.
About the B39 Code Range
The ICD-10 code B39 and its subcodes specifically classify various forms of histoplasmosis, a fungal infection caused by Histoplasma species. These codes help identify different types of histoplasmosis, including pulmonary, disseminated, and African variants, and distinguish between acute, chronic, or unspecified presentations.
This section covers acute and chronic pulmonary histoplasmosis (B39.0 and B39.1), which refer to fungal lung infections often called "pulmonary histoplasmosis." The code B39.3 is for disseminated histoplasmosis, indicating spread beyond the lungs, which may affect the skin and other organs. Code B39.4 addresses histoplasmosis with complications such as retinitis, meningitis, or endocarditis, while B39.5 represents the African histoplasmosis variant (Histoplasmosis duboisii). Lastly, B39.9 is used when histoplasmosis is diagnosed but not specified further. Using these codes accurately supports precise medical documentation and billing for fungal infections caused by Histoplasma, often known as acute pulmonary histoplasmosis, disseminated Histoplasma capsulatum infection, or African histoplasmosis.
Questions About This Page
How many billable codes are in the B39 range?
Of the 8 codes in this range, 7 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the B39 range classify?
The range classifies histoplasmosis. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
