A51.0 ICD-10-CA code: Primary genital syphilis
A51.0 is the ICD-10-CA code for “Primary genital syphilis” in CIHI’s FY 2026–2027 release, in effect from Apr 1, 2026.
Official description
A51.0Primary genital syphilis
ICD-10-CA · Canada · Also written A510
Index terms
Entries in CIHI’s alphabetical index that lead to A51.0. Searching the index by the condition the note names is how coders reach this code.
- Ulcus, durum (syphilitic)
- Bubo, syphilitic (primary)
- Vaginitis (acute), syphilitic (early)
- Lesion (nontraumatic), primary, syphilis
- Syphilis, syphilitic (acquired), primary
- Syphilis, syphilitic (acquired), bubo (primary)
- Syphilis, syphilitic (acquired), penis (chancre)
- Syphilis, syphilitic (acquired), vulva (primary)
- Syphilis, syphilitic (acquired), primary, genital
- Syphilis, syphilitic (acquired), vagina (primary)
- Syphilis, syphilitic (acquired), genital (primary)
- Syphilis, syphilitic (acquired), chancre (multiple)
- Syphilis, syphilitic (acquired), chancre (multiple), Rollet's
- Chancre (genital) (hard) (primary) (seronegative) (seropositive) (syphilitic)
- Chancre (genital) (hard) (primary) (seronegative) (seropositive) (syphilitic), mixed
- Chancre (genital) (hard) (primary) (seronegative) (seropositive) (syphilitic), urethra
- Chancre (genital) (hard) (primary) (seronegative) (seropositive) (syphilitic), hunterian
- Syphilis, syphilitic (acquired), early NEC, symptomatic, primary, except extragenital chancre
- Vulvitis (acute) (allergic) (aphthous) (atrophic) (gangrenous) (hypertrophic) (intertriginous) (senile), syphilitic (early)
Notes for A51.0
As CIHI prints them, with any note A51.0 takes from the headings above it.
Includes
- Syphilitic chancre NOS
- Diseases generally recognized as communicable or transmissibleFrom Chapter 1: Certain infectious and parasitic diseases (A00-B99)
Use additional code
Add a code for this detail when the note documents it.
- Use additional code (U82-U84) to identify resistance to antimicrobial drugsFrom Chapter 1: Certain infectious and parasitic diseases (A00-B99)
Excludes
Conditions classified elsewhere.
- Human immunodeficiency virus [HIV] disease (B24)nonspecific and nongonococcal urethritis (N34.1)Reiter disease (M02.3-)From A50-A64 Infections with a predominantly sexual mode of transmission
- Carrier or suspected carrier of infectious disease (Z22.-)certain localized infections - see body system-related chaptersinfectious and parasitic diseases:• complicating pregnancy, childbirth and the puerperium [except obstetrical tetanus] (O98.-)• specific to the perinatal period [except tetanus neonatorum, whooping cough, congenital syphilis, perinatal gonococcal infection and perinatal human immunodeficiency virus [HIV] disease] (P35-P39)influenza and other acute respiratory infections (J00-J22)From Chapter 1: Certain infectious and parasitic diseases (A00-B99)
Where A51.0 sits
- 1ChapterChapter 1: Certain infectious and parasitic diseases (A00-B99)
- 2Block A50-A64Infections with a predominantly sexual mode of transmission
- 3Category A51Early syphilis
- 4Valid code A51.0Primary genital syphilis
Source and release
- Data release
- ICD-10-CA · FY 2026–2027
- Effective date
- Apr 1, 2026
- Publisher
- CIHI
This page is built from the ICD-10-CA catalog that Vero Codes reads when it suggests codes: Canadian Institute for Health Information’s FY 2026–2027 release, imported from the publisher’s file and checked against it. The description, notes and structured data come from the same record.
Frequently asked questions
What does ICD-10-CA code A51.0 mean?
A51.0 is the ICD-10-CA code for “Primary genital syphilis” in CIHI’s ICD-10-CA FY 2026–2027 release.
Where is A51.0 in ICD-10-CA?
A51.0 sits under A51 Early syphilis, within A50-A64 Infections with a predominantly sexual mode of transmission, within Chapter 1: Certain infectious and parasitic diseases (A00-B99).
What coding notes apply to A51.0?
ICD-10-CA lists Includes, Excludes, Use additional code notes for A51.0, including those from the headings it sits under. They are listed on this page with where each one comes from.
Which ICD-10-CA release does this page use?
It uses CIHI’s FY 2026–2027 release, in effect from Apr 1, 2026 to Mar 31, 2027. It is a reference: confirm the code against the current list and the payer’s rules before you submit it.