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 2026, 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.
Trachoma
A chronic infection of the CONJUNCTIVA and CORNEA caused by CHLAMYDIA TRACHOMATIS.
About the A74 Code Range
The ICD-10 code section A74 is used to classify various diseases caused by chlamydiae bacteria, including specific infections like chlamydial conjunctivitis (A74.0) and chlamydial peritonitis (A74.81). These codes help identify infections caused by Chlamydia species beyond the most common genital infections.
This set of codes covers a range of conditions caused by chlamydiae, such as chronic chlamydial follicular conjunctivitis, also known as trachoma or inclusion conjunctivitis of the adult under A74.0. The code A74.81 is designated for Fitz-Hugh-Curtis syndrome, an inflammatory condition of the peritoneum associated with Chlamydia infection. Other less common manifestations like chlamydial colitis, dacryoadenitis, and neonatal infections are captured under A74.8 and A74.89. When the infection lacks specific details, A74.9 is used for an unspecified chlamydial infection, including those complicating pregnancy or childbirth. This grouping ensures that health professionals can accurately code and track diverse chlamydial diseases beyond typical sexually transmitted infections for comprehensive clinical documentation and billing.
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, 2025 through September 30, 2026. 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 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
