A51.9
A51.9 — Early syphilis, unspecified
Billable / specific codeICD-10-CM
A51.9 is a billable, specific ICD-10-CM code for early syphilis, unspecified. It is valid for submission on a claim.
Risk adjustment
A51.9 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
How A51.9 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to A51.9.
- Syphilis, syphilitic›early
- Syphilis, syphilitic›recently acquired, symptomatic
- Syphilis, syphilitic›age under 2 years NOS›acquired
- Syphilis, syphilitic›early›relapse(treated, untreated)
- Syphilis, syphilitic›early›symptomatic
Related codes at this level
Codes that share A51. If A51.9 is not quite right, the correct code is usually one of these.
Questions about A51.9
- Is A51.9 a billable ICD-10-CM code?
- Yes. A51.9 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does A51.9 sit in the tabular list?
- Certain infectious and parasitic diseases (A00-B99), in the block Infections with a predominantly sexual mode of transmission (A50-A64).