2027 ICD-10-CM Diagnosis Code A64Unspecified sexually transmitted disease
ICD-10-CM Codes›A00–B99›A50-A64›A64
- Billable — Valid for Submission
- Not Chronic
A64 is a billable ICD-10-CM diagnosis code for unspecified sexually transmitted disease. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 727 through 728, 742 through 743, 757 through 759. Coders also document this condition as sexually transmitted bacterial disease affecting skin. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Sexually transmitted infections (excluding HIV and hepatitis).
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Sexually transmitted bacterial disease affecting skin
- Sexually transmitted infectious disease
- Venereal disease in pregnancy
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to A64: its own notes plus those printed at block A50-A64 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- diseases generally recognized as communicable or transmissible
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- human immunodeficiency virus [HIV] disease (B20)
- 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)
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- code to identify resistance to antimicrobial drugs (Z16.-)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name A64, its category, or a range that includes it.
Applicable To 1
These notes mention A64.
- O98.3 Other infections with a predominantly sexual mode of transmission complicating pregnancy, childbirth and the puerperium
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Disease, diseased See Also: Syndrome;
venereal See Also: Disease, sexually transmitted; A64
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Sexually Transmitted Infections
Sexually transmitted infections (STIs) are infections that are passed from one person to another through sexual contact. If not treated, an STI can develop into a sexually transmitted disease (STD).
The full article covers:
- What are sexually transmitted infections (STIs)?
- What causes sexually transmitted infections (STIs)?
- Who is affected by sexually transmitted infections (STIs)?
- What are the symptoms of sexually transmitted infections (STIs)?
- How are sexually transmitted infections (STIs) diagnosed?
- What are the treatments for sexually transmitted infections (STIs)?
- Can sexually transmitted infections (STIs) be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert A64 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About A64Overview
What is the ICD-10 code for unspecified sexually transmitted disease?
The ICD-10-CM code for unspecified sexually transmitted disease is A64. It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is A64 (Unspecified sexually transmitted disease) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report unspecified sexually transmitted disease on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does A64 group to?
When unspecified sexually transmitted disease is the principal diagnosis on an inpatient stay, it groups to MS-DRG 742, 759, 727, 743, 728, 758, 757, with relative weights from 0.7687 to 1.8448 depending on complications. Higher weights mean higher Medicare reimbursement.
Can A64 be reported with N34.1?
Not as a rule. The Excludes1 note at block A50-A64, which applies to A64, lists "nonspecific and nongonococcal urethritis (N34.1)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).
What is the ICD-9 equivalent of A64?
Under the General Equivalence Mappings, unspecified sexually transmitted disease converts to ICD-9-CM 099.9 (venereal disease NOS). The mapping is a direct match.
