10ICD Code Hub

Z21

Billable code

Asymptomatic human immunodeficiency virus [HIV] infection status

The ICD-10 code for asymptomatic human immunodeficiency virus [hiv] infection status is Z21.

Clinical notes

Code first

This code represents a manifestation of an underlying disease. Coding convention requires the underlying (etiology) code to be sequenced first, with this code listed second.

  • Human immunodeficiency virus [HIV] disease complicating pregnancy, childbirth and the puerperium, if applicable (O98.7-)

Excludes1 (not coded here)

An Excludes1 note is a pure exclusion: the excluded condition and this code should never be reported together, because the two conditions cannot occur at the same time (e.g. a congenital form vs. an acquired form of the same disease).

  • acquired immunodeficiency syndrome (B20)
  • contact with human immunodeficiency virus [HIV] (Z20.6)
  • exposure to human immunodeficiency virus [HIV] (Z20.6)
  • human immunodeficiency virus [HIV] disease (B20)
  • inconclusive laboratory evidence of human immunodeficiency virus [HIV] (R75)

Also known as

Alternate wording, synonyms, or specific conditions that fall under this code, listed to help confirm you've picked the right one.

  • HIV positive NOS

Documentation support

General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.

Related codes in this category

ICD-9-CM equivalent

Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.

View full ICD-10 → ICD-9 crosswalk →

Associated MS-DRGs

Z21 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.

Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.