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ICD-10-CM 2027 diagnosis code

B39.9Histoplasmosis, unspecified

✓ Billable / specific

B39.9 is a valid, billable ICD-10-CM code for histoplasmosis, unspecified. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Looking up by condition? See ICD-10 code for Histoplasmosis.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About B39.9

B39.9 is the ICD-10-CM diagnosis code for histoplasmosis, unspecified. It belongs to category B39 (histoplasmosis), block B35-B49 (mycoses) and chapter 1 (certain infectious and parasitic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within B39, choose B39.9 (unspecified) only when documentation doesn't support a more specific option: acute pulmonary histoplasmosis capsulati (B39.0), chronic pulmonary histoplasmosis capsulati (B39.1), pulmonary histoplasmosis capsulati, unspecified (B39.2), disseminated histoplasmosis capsulati (B39.3), capsulati, unspecified (B39.4) and duboisii (B39.5).

Code first: associated AIDS (B20).

Use an additional code for any associated manifestations, such as: endocarditis (I39), meningitis (G02), pericarditis (I32) and retinitis (H32).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC, relative weight 2.1859), DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC, relative weight 1.0235), DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC, relative weight 0.6787), DRG 974 (HIV with Major Related Condition with MCC, relative weight 3.0506), DRG 975 (HIV with Major Related Condition with CC, relative weight 1.3252) and DRG 976 (HIV with Major Related Condition without CC/MCC, relative weight 0.8124), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites) and MDC 25 (Human Immunodeficiency Virus Infections), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 115.90 (histoplasmosis, unspecified, without mention of manifestation).

Notes that apply from higher levels

Instructions written at a parent level also apply to B39.9.

› From B39 Histoplasmosis
Code first
  • associated AIDS (B20)
Use additional code
  • code for any associated manifestations, such as:
  • endocarditis (I39)
  • meningitis (G02)
  • pericarditis (I32)
  • retinitis (H32)

Broader instructions also apply from B35-B49 Mycoses and Chapter 1: Certain infectious and parasitic diseases.

Alphabetic index entries

3 entries

Terms in the official ICD-10-CM index that lead to B39.9.

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

ICD-9-CM equivalent

Converter →
  • 115.90Histoplasmosis, unspecified, without mention of manifestationapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about B39.9

Is B39.9 billable?

Yes. B39.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can B39.9 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict B39.9 as a principal diagnosis.

Is B39.9 a CC or MCC?

No. B39.9 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does B39.9 group to?

B39.9 is used in the MS-DRG v44.0 logic for MS-DRG 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC), MS-DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC), MS-DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC), MS-DRG 974 (HIV with Major Related Condition with MCC), MS-DRG 975 (HIV with Major Related Condition with CC) and MS-DRG 976 (HIV with Major Related Condition without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for B39.9?

The CMS General Equivalence Mappings map B39.9 to ICD-9-CM 115.90.