A64 — Unspecified sexually transmitted disease
Is A64 billable?
Yes, but A64 is an unspecified code. A64 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, A64 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting A64.
A64 at a glance
| Code | A64 |
|---|---|
| Description | Unspecified sexually transmitted disease |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does A64 group to?
A64 sits in MDC 12 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 727Inflammation of the Male Reproductive System with MCCmedical
- 728Inflammation of the Male Reproductive System without MCCmedical
How is A64 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to A64. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Disease, diseased › sexually transmitted
- Disease, diseased › venereal
- Venereal › disease
Excludes1 — never code together — inherited from A50-A64
The conditions below can never be reported together with A64 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Use additional code — inherited from Chapter 1
Report an additional code alongside A64 to fully describe the condition. A64 is sequenced first.
- code to identify resistance to antimicrobial drugs (Z16.-)
Excludes2 — not included here — inherited from Chapter 1
The conditions below are not part of A64, but a patient may have both at the same time. When documentation supports it, A64 and the excluded code may both be reported.
- carrier or suspected carrier of infectious disease (Z22.-)
- certain localized infections - see body system-related chapters
- 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)
Excludes2 — not included here — inherited from A50-A64
The conditions below are not part of A64, but a patient may have both at the same time. When documentation supports it, A64 and the excluded code may both be reported.
- human immunodeficiency virus [HIV] disease (B20)
How long has A64 existed?
A64 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.