A51
Non-billableEarly syphilis
Early syphilis
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Status
Non-billable / Header
Block
A50-A64
Child Codes
7
Coding Notes
Includes
Conditions included under this code
- diseases generally recognized as communicable or transmissible
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- carrier or suspected carrier of infectious disease (Z22.-)
- infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
- infectious and parasitic diseases specific to the perinatal period (P35-P39)
- influenza and other acute respiratory infections (J00-J22)
- human immunodeficiency virus [HIV] disease (B20)
Use Additional Code
Additional codes that should follow this code
- code to identify resistance to antimicrobial drugs (Z16.-)
Child Codes (7)
Also Known As / Clinical Terms
Frequently Asked Questions
What is ICD-10 code A51?
ICD-10-CM code A51 represents "Early syphilis". It is a non-billable header code — use a more specific child code for billing purposes.
Is A51 a billable code?
No, A51 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 7 child codes under A51.
What chapter is A51 in?
A51 is in Chapter 1: Certain Infectious and Parasitic Diseases (codes A00-B99).
What codes cannot be used with A51?
A51 has Excludes1 notes indicating codes that cannot be used together with it, including: certain localized infections - see body system-related chapters; nonspecific and nongonococcal urethritis (N34.1); Reiter's disease (M02.3-).
What are the subcategories under A51?
A51 has 7 child codes, including: A51.0 (Primary genital syphilis), A51.1 (Primary anal syphilis), A51.2 (Primary syphilis of other sites), A51.3 (Secondary syphilis of skin and mucous membranes), and 3 more.
Are additional codes required with A51?
Yes, when using A51 you should also code: code to identify resistance to antimicrobial drugs (Z16.-).
What are the UMLS CUIs for A51?
A51 is linked to 1 UMLS Concept Unique Identifier: C0348148. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.