ICD-10-CM Tabular Index · Chapter 1 · FY 2027 A50–A64
Infections with a predominantly sexual mode of transmission (A50-A64) ICD-10-CM
The A50–A64 section covers infections with a predominantly sexual mode of transmission with 169 ICD-10-CM diagnosis codes, of which 142 are billable in fiscal year 2027. The section is organized into the 13 code ranges listed below.
✓ Built from the official CMS FY 2027 datasetEffective Oct 1, 2026 – Sep 30, 2027
13
Code Ranges
169
Diagnosis Codes
142
Billable Codes
A50–A64
Code Range
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
The info icon previews the code ranges inside each row and its instructional notations from the official Tabular List.
About the A50–A64 Code Range
Most infections in this group spread through sexual contact. Congenital syphilis is the exception described here: it is acquired before birth.
Syphilis categories separate congenital, early, late, and other or unspecified forms. A50 divides congenital syphilis by early or late presentation, symptoms, and affected site. A51 distinguishes primary, secondary, and latent early syphilis, with further divisions by site. A52 separates late syphilis by affected body system and symptoms. A53 covers syphilis that is otherwise unspecified.
Other categories distinguish the infection and, where shown, its site. A54 covers gonococcal infection, while A55 and A56 cover chlamydial diseases. A57 is chancroid, and A58 is granuloma inguinale. A59 divides trichomoniasis by site, as does A60 for genital and anal herpesviral infections. A63 includes anogenital warts, while A64 identifies an unspecified sexually transmitted disease.
Questions About This Page
How many codes are in the A50-A64 range?
The A50-A64 range contains 169 ICD-10-CM diagnosis codes in FY 2027. 142 of them are billable, and the rest are category headers that organize the section.
What conditions does A50-A64 cover?
The range covers infections with a predominantly sexual mode of transmission. The code ranges listed above break it into groups of related conditions, and each one links to its own page with the full code list.
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
This note appears immediately under a three character code title to further define, or give examples of, the content of the category.
sexually transmitted diseases due to Chlamydia
trachomatis
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
