What does ICD-10 code A64 mean?

ICD-10 code A64 is the standardized code used for unspecified sexually transmitted disease in medical records and coding systems.

When is ICD-10 code A64 used?

Doctors, hospitals, and insurers may use ICD-10 code A64 when recording unspecified sexually transmitted disease in a standardized format.

Does ICD-10 code A64 confirm a diagnosis?

No. A code helps standardize documentation and claims, but it should not be read as a substitute for a clinician's full assessment.

ICD10BillableValid for clinical use

ICD-10 Code A64: Unspecified sexually transmitted disease

Name: ICD-10 Code A64: Unspecified sexually transmitted disease
Creator: HealthAssure Clinical Team
Published: 2026-05-26T05:25:39.445Z

A64 is a billable ICD-10 diagnosis code used to classify Unspecified sexually transmitted disease in medical records and claims. You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records. ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Certain infectious and parasitic diseases (A00-B99).

Reviewed by HealthAssure Clinical TeamUpdated 26 May 2026

What is this code?

ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Certain infectious and parasitic diseases (A00-B99).

When is it used?

May be used when a clinician documents unspecified sexually transmitted disease in a patient's medical record.
May appear in hospital records, claims, referrals, and clinical documentation.
This code can be used as a clinically usable diagnosis entry in standardized coding workflows.

What it does not mean

A code alone does not explain severity, treatment plan, or outcome.
A medical code should not be treated as a substitute for a doctor's diagnosis or advice.

Code hierarchy

chapter

1Certain infectious and parasitic diseases (A00-B99)

block

A50-A64Infections with a predominantly sexual mode of transmission

currentA50-A64

Where you may see this code

You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.

Related specialists

Infectious Disease SpecialistGeneral Physician

Sibling codes

A50Congenital syphilis A51Early syphilis A52Late syphilis A53Other and unspecified syphilis A54Gonococcal infection A55Chlamydial lymphogranuloma (venereum)billable A56Other sexually transmitted chlamydial diseases A57Chancroidbillable A58Granuloma inguinalebillable A59Trichomoniasis A60Anogenital herpesviral [herpes simplex] infections A63Other predominantly sexually transmitted diseases, not elsewhere classified

Mapped diagnoses and classifications

SNOMED_CT 8098009high

Sexually transmitted infectious disease

Source: SNOMED International ICD-10 map

Coding guidelines

Compatibility

Legacy and official ICD code match exactly.

Legacy codes

A64

Common synonyms

Unspecified sexually transmitted disease

Frequently asked questions

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.