ICD-10-CM 2027
ICD-10 code for chromomycosis
From the official ICD-10-CM alphabetic index entry “Chromomycosis”. Page updated September 29, 2026.
About coding chromomycosis
The ICD-10-CM code for chromomycosis is B43.9 (Chromomycosis, unspecified). The official index lists 6 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on B43.9.
Within B43, choose B43.9 (Chromomycosis, unspecified) only when documentation doesn't support a more specific option: cutaneous chromomycosis (B43.0), pheomycotic brain abscess (B43.1), subcutaneous pheomycotic abscess and cyst (B43.2) and other forms of chromomycosis (B43.8).
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) and DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC, relative weight 0.6787), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific chromomycosis codes (official index)
Common questions about chromomycosis ICD-10 codes
What is the ICD-10 code for chromomycosis?
- B43.9 — Chromomycosis, unspecified. More specific codes apply when the documentation supports them: B43.1, B43.1, B43.0, B43.0 and others below.
What is the ICD-10 code for brain abscess chromomycosis?
- B43.1 — Pheomycotic brain abscess.
What is the ICD-10 code for cerebral chromomycosis?
- B43.1 — Pheomycotic brain abscess.
What is the ICD-10 code for cutaneous chromomycosis?
- B43.0 — Cutaneous chromomycosis.
What is the ICD-10 code for skin chromomycosis?
- B43.0 — Cutaneous chromomycosis.
What is the ICD-10 code for subcutaneous abscess or cyst chromomycosis?
- B43.2 — Subcutaneous pheomycotic abscess and cyst.
Is B43.9 billable?
- Yes. B43.9 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can B43.9 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict B43.9 as a principal diagnosis.
Is B43.9 a CC or MCC?
- No. B43.9 is neither a CC nor an MCC under MS-DRG v44.0.