DxCodebookFY2027 · Oct 1, 2026 – Sep 30, 2027

Z21 diagnosis code · Billable category · FY2027

Z21 Asymptomatic human immunodeficiency virus [HIV] infection status

  • Billable
  • Not CC/MCC
  • HCC 1
  • POA reported

Z21 ICD-10 code: a billable diagnosis code in FY2027; the category has no subdivisions.

Where it sits

  1. Chapter 21 Factors influencing health status and contact with health services (Z00-Z99)
  2. Z20-Z29 Persons with potential health hazards related to communicable diseases (Z20-Z29)
  3. Z21 Asymptomatic human immunodeficiency virus [HIV] infection status
CC / MCC
Neither
MS-DRG
865-866
HCC V28
1
POA
Reported
Code Editor
Questionable adm.
Index entries
7

Instructions

At Z21

Inclusion terms

  • HIV positive NOS

Excludes1

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

Code first

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

Notes that also apply

Chapter 21 instructions (Notes 3): printed on the chapter 21 page.

Index entries

  • HIVpositive, seropositive → Z21
  • Status (post)human immunodeficiency virus (HIV) infection, asymptomatic → Z21
  • Syndromeretroviral seroconversion (acute) → Z21
  • Syndromeseroconversion, retroviral (acute) → Z21
  • Humanimmunodeficiency virus (HIV) disease (infection)asymptomatic status → Z21
  • Test, tests, testing (for)HIV (human immunodeficiency virus)positive → Z21
  • Test, tests, testing (for)HIV (human immunodeficiency virus)seropositive → Z21

NCHS Alphabetic Index. Index first, then the Tabular List.

Medicare grouping and edits

CMS files for Z21
CC / MCCNeither
Appendix BMDC 18 Infectious and Parasitic Diseases, Systemic or Unspecified Sites, MS-DRG 865-866 (Viral Illness with MCC…)
Code EditorQuestionable admission when principal diagnosis
POAReported
HCC V28HCC 1 HIV/AIDS

CMS: MS-DRG v44 (Appendix B, C), MCE v44, POA list FY2027, 2027 Initial ICD-10-CM Mappings. What the rows mean.

Hierarchy