Primary anal syphilis

This code represents the initial stage of syphilis infection manifesting as a chancre located in the anal region. It is a sexually transmitted infection caused by the bacterium Treponema pallidum, characterized by a painless ulcer.

Apply this code when documentation clearly indicates a primary syphilitic lesion (chancre) found in or around the anus. Supporting documentation includes physical exam findings, positive serological tests for syphilis (e.g., RPR, VDRL, FTA-ABS), and sometimes biopsy results.

• Differentiate from secondary or latent syphilis, which have distinct ICD-10-CM codes.
• Ensure the documentation specifies "primary" and "anal" to support this specific code.
• Consider co-occurring sexually transmitted infections and code them separately if present.