ICD-10-CM 2027
ICD-10 code for ulcer syphilis
From the official ICD-10-CM alphabetic index entry “Syphilis, syphilitic (acquired) › ulcer (any site) (early) (secondary)”. Page updated September 29, 2026.
About coding ulcer syphilis
The ICD-10-CM code for ulcer syphilis is A51.39 (Other secondary syphilis of skin). The official index lists 3 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on A51.39.
Within A51.3, choose A51.39 (Other secondary syphilis of skin) only when documentation doesn't support a more specific option: Condyloma latum (A51.31) and syphilitic alopecia (A51.32).
Don't report A51.39 together with the conditions in its Excludes1 note: late syphilitic leukoderma (A52.79).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
More specific ulcer syphilis codes (official index)
Don't confuse with (Excludes1 for A51.39)
- late syphilitic leukoderma (A52.79)
Common questions about ulcer syphilis ICD-10 codes
What is the ICD-10 code for ulcer syphilis?
- A51.39 — Other secondary syphilis of skin. More specific codes apply when the documentation supports them: A52.79, A52.79, A52.11.
What is the ICD-10 code for late ulcer syphilis?
- A52.79 — Other symptomatic late syphilis.
What is the ICD-10 code for perforating ulcer syphilis?
- A52.79 — Other symptomatic late syphilis.
Is A51.39 billable?
- Yes. A51.39 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A51.39 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A51.39 as a principal diagnosis.
Is A51.39 a CC or MCC?
- A51.39 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.