ICD-10 · PDGM grouping
A51 Early syphilis
All 15 codes in the A51 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
15
Can lead a claim
15
Cannot lead a claim
0
What CMS assigns to A51
All 15 codes group to MMTA - Infectious Disease, Neoplasms, and Blood-Forming Diseases (14) and Neuro Rehabilitation (1). None of the 15 is assigned a comorbidity subgroup. Every code can lead a claim.
Every code in A51
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| A51.0 | Primary genital syphilis | Can lead a claim | K | None |
| A51.1 | Primary anal syphilis | Can lead a claim | K | None |
| A51.2 | Primary syphilis of other sites | Can lead a claim | K | None |
| A51.3 Secondary syphilis of skin and mucous membranes | ||||
| A51.31 | Condyloma latum | Can lead a claim | K | None |
| A51.32 | Syphilitic alopecia | Can lead a claim | K | None |
| A51.39 | Other secondary syphilis of skin | Can lead a claim | K | None |
| A51.4 Other secondary syphilis | ||||
| A51.41 | Secondary syphilitic meningitis | Can lead a claim | B | None |
| A51.42 | Secondary syphilitic female pelvic disease | Can lead a claim | K | None |
| A51.43 | Secondary syphilitic oculopathy | Can lead a claim | K | None |
| A51.44 | Secondary syphilitic nephritis | Can lead a claim | K | None |
| A51.45 | Secondary syphilitic hepatitis | Can lead a claim | K | None |
| A51.46 | Secondary syphilitic osteopathy | Can lead a claim | K | None |
| A51.49 | Other secondary syphilitic conditions | Can lead a claim | K | None |
| A51.5 | Early syphilis, latent | Can lead a claim | K | None |
| A51.9 | Early syphilis, unspecified | Can lead a claim | K | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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