2021 ICD-10-CM Code Z21

Asymptomatic human immunodeficiency virus [HIV] infection status

Version 2021
Billable Code
Questionable Admission Codes
MS-DRG Mapping

Valid for Submission

Z21 is a billable diagnosis code used to specify a medical diagnosis of asymptomatic human immunodeficiency virus [hiv] infection status. The code Z21 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

The ICD-10-CM code Z21 might also be used to specify conditions or terms like asymptomatic human immunodeficiency virus a1 infection, asymptomatic human immunodeficiency virus a2 infection, asymptomatic human immunodeficiency virus infection, asymptomatic human immunodeficiency virus infection, asymptomatic human immunodeficiency virus infection in pregnancy , finding of hiv status, etc.

The code Z21 is not usually sufficient justification for admission to an acute care hospital when used as a principal diagnosis.

ICD-10:Z21
Short Description:Asymptomatic human immunodeficiency virus infection status
Long Description:Asymptomatic human immunodeficiency virus [HIV] infection status

Code Classification

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code Z21:


Inclusion Terms

Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.

Code First

Code First
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.

Type 1 Excludes

Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code Z21 are found in the index:

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10 Code Edits are applicable to this code:

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Convert Z21 to ICD-9 Code

Information for Patients


HIV/AIDS

Also called: AIDS, Acquired immunodeficiency syndrome, HIV, Human immunodeficiency virus

HIV stands for human immunodeficiency virus. It harms your immune system by destroying the white blood cells that fight infection. This puts you at risk for serious infections and certain cancers. AIDS stands for acquired immunodeficiency syndrome. It is the final stage of infection with HIV. Not everyone with HIV develops AIDS.

HIV most often spreads through unprotected sex with a person who has HIV. It may also spread by sharing drug needles or through contact with the blood of a person who has HIV. Women can give it to their babies during pregnancy or childbirth.

The first signs of HIV infection may be swollen glands and flu-like symptoms. These may come and go within two to four weeks. Severe symptoms may not appear until months or years later.

A blood test can tell if you have HIV infection. Your health care provider can do the test, or you can use a home testing kit. Or to find free testing sites, call the national referral hotline at 1-800-CDC-INFO (1-800-232-4636 in English and en español; 1-888-232-6348 - TTY).

There is no cure, but there are many medicines that fight HIV infection and lower the risk of infecting others. People who get early treatment can live with the disease for a long time.

Strategies to reduce the risk of HIV infection include not having sex, limiting your number of sexual partners, never sharing needles, and using condoms the right way every time you have sex. People who are at high risk may take HIV prevention medicines.


[Learn More in MedlinePlus]

Code History

  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016 (First year ICD-10-CM implemented into the HIPAA code set)