Other diseases caused by chlamydiae (A74) ICD-10-CM
The A74 code range covers other diseases caused by chlamydiae with 6 ICD-10-CM diagnosis codes. 4 of them are billable and valid for claim submission in fiscal year 2027, and the category headers group them but cannot themselves be billed.
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.
- neonatal chlamydial conjunctivitis P39.1
- neonatal chlamydial pneumonia P23.1
- Reiter's disease M02.3
- sexually transmitted chlamydial diseases A55 A56
Type 2 Excludes
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.
- chlamydial pneumonia J16.0
Codes in the A74 Range 6 codes · 4 billable
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the A74 range.
Chlamydial Infection
An infection that is caused by Chlamydia trachomatis.
About the A74 Code Range
These diseases are caused by chlamydiae and include an eye condition and inflammation of the abdominal lining.
A74 separates chlamydial conjunctivitis, an eye condition, from other chlamydial diseases and unspecified infection. A74.8 divides other diseases into peritonitis, inflammation of the abdominal lining, at A74.81 and other diseases at A74.89. A74.9 identifies chlamydial infection without a specified type.
Questions About This Page
How many billable codes are in the A74 range?
Of the 6 codes in this range, 4 are billable and valid for claim submission from October 1, 2026 through September 30, 2027. Category header codes group them but cannot be reported on claims.
What does the A74 range classify?
The range classifies other diseases caused by chlamydiae. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2027 ICD-10-CM Tabular List and order file, effective October 1, 2026 through September 30, 2027.
