ICD-10 Code A51.4 – Other secondary syphilis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A51.4 – Other secondary syphilis
What it is
A51.4 identifies secondary syphilis when the presentation does not fit a more specific secondary syphilis code. Use it for confirmed secondary-stage infection with other documented manifestations.
Clinical signs
Clinical features vary; refer to documentation. Secondary syphilis may include a generalized rash, mucous patches, condyloma lata, lymphadenopathy, or systemic symptoms, but the chart should support the specific presentation.
When to use this code
Use this code when the provider documents secondary syphilis and the record does not specify another secondary syphilis subtype. It also fits cases described as “other” secondary syphilis or when manifestations are present but not otherwise classifiable.
Check that the diagnosis is active and not a history of infection or screening encounter. If the note identifies a more specific secondary syphilis manifestation, code that detail instead of this unspecified option.
Do not use for
Do not use A51.4 for primary, latent, tertiary, or congenital syphilis. Do not use it for screening, exposure without diagnosis, or a past history of syphilis.
Coding tip
Code A51.4 only when the provider documents secondary syphilis and no more specific secondary-stage code is supported by the record.