A56 — Other sexually transmitted chlamydial diseases
A56 is a non-billable header ICD-10-CM code for other sexually transmitted chlamydial diseases. It cannot be billed on its own: choose one of the more specific child codes below.
Excludes1 — never code together
These conditions cannot occur together. Billing both on the same encounter is a denial.
Excludes2 — not included here, but may coexist
The excluded condition is not part of this code, but a patient can have both. You may code both.
Includes
Conditions this code covers.
- sexually transmitted diseases due to Chlamydia
- trachomatis
Other codes that can never be billed with A56
These codes carry an Excludes1 note pointing at A56. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading A56 alone.
Risk adjustment
A56 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Code to one of these instead A56
6 child codes. Green means billable.
- A56.0Chlamydial infection of lower genitourinary tract
- A56.1Chlamydial infection of pelviperitoneum and other genitourinary organs
- A56.2Chlamydial infection of genitourinary tract, unspecified
- A56.3Chlamydial infection of anus and rectum
- A56.4Chlamydial infection of pharynx
- A56.8Sexually transmitted chlamydial infection of other sites
Questions about A56
- Is A56 a billable ICD-10-CM code?
- No. A56 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
- Where does A56 sit in the tabular list?
- Certain infectious and parasitic diseases (A00-B99), in the block Infections with a predominantly sexual mode of transmission (A50-A64).
- What cannot be coded together with A56?
- A56 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.