ICD-10-CM Diagnosis Code A64 - Unspecified sexually transmitted disease (original) (raw)

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ICD List 2025-2026 Edition

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Unspecified sexually transmitted disease

ICD-10-CM Code:

A64

ICD-10 Code for:

Unspecified sexually transmitted disease

Is Billable?

Yes - Valid for Submission

Chronic Condition Indicator: [1]

Not chronic

Code Navigator:

A64 is a billable diagnosis code used to specify a medical diagnosis of unspecified sexually transmitted disease. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2025 through September 30, 2026.

Unspecified diagnosis codes like A64 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

  1. Code Information
  2. Approximate Synonyms
  3. Clinical Classification
  4. Tabular List of Diseases and Injuries
  5. Index to Diseases and Injuries References
  7. Diagnostic Related Groups Mapping
  8. Convert to ICD-9 Code
  9. Patient Education
  10. Code History

The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.

Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.

They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.

CCSR Code: INF010

Inpatient Default: Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.

Outpatient Default: Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

References found for this diagnosis code in the External Cause of Injuries Index:

Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.

ICD-9-CM: 099.9

This is a direct match with no additional mapping qualifiers. The absence of a flag generally means the mapping is considered exact or precise. In other words, the ICD-10 code maps cleanly to the ICD-9 code without qualification, approximation, or needing multiple codes.

Sexually Transmitted Infections

What are sexually transmitted infections (STIs)?

Sexually transmitted infections (STIs) are infections that are passed from one person to another through sexual contact. If not treated, a STI can develop into a sexually transmitted disease (STD).

STIs are usually spread during vaginal, oral, or anal sex. But sometimes they can spread through other sexual contact involving the penis, vagina, mouth, or anus. This is because some STIs, like herpes and HPV, are spread by skin-to-skin contact.

Some STIs can be passed to the fetus during pregnancy or childbirth. Other ways that some STIs may spread include while breastfeeding, through blood transfusions, or by sharing needles.

There are more than 20 types of STIs, including:

What causes sexually transmitted infections (STIs)?

STIs can be caused by bacteria, viruses, and parasites.

Who is affected by sexually transmitted infections (STIs)?

Most STIs affect both men and women, but in many cases the health problems they cause can be more severe for women. If an STI is passed to a fetus during pregnancy or childbirth, it can cause serious health problems.

What are the symptoms of sexually transmitted infections (STIs)?

STIs don't always cause symptoms or may only cause mild symptoms. So, it is possible to have an infection and not know it. And even without symptoms, STIs can still be harmful and may be passed on during sex.

If you do have symptoms, they could include:

How are sexually transmitted infections (STIs) diagnosed?

If you are sexually active, you should talk to your health care provider about your risk for STIs and whether you need to be tested. This is especially important since many STIs do not usually cause symptoms.

Some STIs may be diagnosed during a physical exam or through STI testing. Some tests involve a microscopic examination of a sore or fluid swabbed from the vagina, penis, or anus. Blood tests can diagnose other types of STIs.

What are the treatments for sexually transmitted infections (STIs)?

Antibiotics can treat STIs that are caused by bacteria or parasites. There is no cure for STIs caused by viruses, but antiviral medicines can often help with the symptoms and lower your risk of spreading the infection.

It's important to get treatment if you have an STI. Some types of STIs can cause serious health problems if they are not treated. Talk to your provider about how long to not have sex after treatment to avoid passing the infection back and forth with your partner.

Can sexually transmitted infections (STIs) be prevented?

The surest way to protect yourself against STIs is to not have sex.

If you do decide to have sex, you can lower your risk of getting an STI by:

[Learn More in MedlinePlus]