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Alphabetic Index and Tabular path
HCC Buddy public API, FY2026 Apr updateSource load source requiredSource year 2026Updated 2026-04-01

Index trail

Asymptomatic human immunodeficiency virus [HIV] infection status

See Tabular List: Z21

Z21, Asymptomatic human immunodeficiency virus [HIV] infection status

Selected code, source checked for the selected effective period

Commonly confused codes

official source

Not listed for this effective period.

Code details and official notes

Z21

Asymptomatic human immunodeficiency virus [HIV] infection status

Open the shareable code page for Z21→
billableHCC mapped

Includes

official source
  • HIV positive NOS

Excludes 1

official source
  • 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)

Excludes 2

official source

No Excludes 2 note is listed in this source payload.

Code First

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

Use Additional

official source

Not listed for this effective period.

Code Also

official source

Not listed for this effective period.

7th character

official source

Not listed for this code in the selected Tabular payload.

Placeholder X

official source

Not listed for this code in the selected Tabular payload.

Laterality

official source

No laterality instruction is listed for this code in the selected Tabular payload.

Effective period

source required
  • FY2026 Apr update
  • Source year 2026
  • Updated 2026-04-01
  • HCC Buddy public API
HCC Buddy
HCC Buddy
Alphabetic Index and Tabular path
HCC Buddy public API, FY2026 Apr updateSource load source requiredSource year 2026Updated 2026-04-01

Index trail

Asymptomatic human immunodeficiency virus [HIV] infection status

See Tabular List: Z21

Z21, Asymptomatic human immunodeficiency virus [HIV] infection status

Selected code, source checked for the selected effective period

Commonly confused codes

official source

Not listed for this effective period.

Code details and official notes

Z21

Asymptomatic human immunodeficiency virus [HIV] infection status

Open the shareable code page for Z21→
billableHCC mapped

Includes

official source
  • HIV positive NOS

Excludes 1

official source
  • 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)

Excludes 2

official source

No Excludes 2 note is listed in this source payload.

Code First

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

Use Additional

official source

Not listed for this effective period.

Code Also

official source

Not listed for this effective period.

7th character

official source

Not listed for this code in the selected Tabular payload.

Placeholder X

official source

Not listed for this code in the selected Tabular payload.

Laterality

official source

No laterality instruction is listed for this code in the selected Tabular payload.

Effective period

source required
  • FY2026 Apr update
  • Source year 2026
  • Updated 2026-04-01
  • HCC Buddy public API
HCC Buddy Insights

HCC Mapping

HCC 1 HIV/AIDS (V28)HCC 1 HIV/AIDS (V24)HCC 1 HIV/AIDS (RxHCC)HCC 1 HIV/AIDS (ESRD/PACE)HCC 1 HHS-HCC 1; HHS-HCC 2026 benefit year (HHS-HCC)

RAF Value

V28: RAF: 0.301V24: RAF: 0.335RxHCC: RAF: 8.523ESRD/PACE: RAF: 0.122HHS-HCC: RAF: Varies by metal level

Model Period

FY2026 Apr update

Source

source required

Audit Caution

Close codes need documentation support before selection. Do not assume relationships.
Reviewed by the HCC Buddy Coding Team

HCC Buddy workflow band

HCC mapping, RAF, MEAT, source trail, and audit caution stay in view.

MEAT supportaudit cautionsource required

V28

HCC 1

HIV/AIDS

RAF: 0.301

V24

HCC 1

HIV/AIDS

RAF: 0.335

RxHCC

RxHCC 1

HIV/AIDS

RAF: 8.523

ESRD/PACE

HCC 1

HIV/AIDS

RAF: 0.122

HHS-HCC

HCC 1

HHS-HCC 1; HHS-HCC 2026 benefit year

RAF: Varies by metal level

MEAT checklist

Reviewed by the HCC Buddy Coding Team

Monitor, Evaluate, Assess, or Treat must be supported in the provider note.

HCC Buddy guidance, not official ICD-10-CM text.

Audit caution

Reviewed by the HCC Buddy Coding Team

Close codes need documentation support before selection. Do not assume relationships.

HCC Buddy guidance, not official ICD-10-CM text.

Reviewer sign-off

Reviewed by the HCC Buddy Coding Team

MEAT, documentation support, audit cautions, and close-code guidance are reviewed and approved for this effective period.

HCC Buddy enrichment is separate from official source text.

Last updated: April 1, 2026 · Not a substitute for official coding guidelines. No PHI or patient data.
HCC Buddy Code Card
FY 2026 Apr update
Z21Billable

Asymptomatic human immunodeficiency virus [HIV] infection status

CMS-HCC V28

HCC 1

RAF 0.301

CMS-HCC V24

HCC 1

RAF 0.335

RxHCC

RxHCC 1

RAF 8.523

Reviewed by the HCC Buddy Coding TeamFY2026 Apr update

Code

Z21

V28 HCC

HCC 1

RAF

0.301

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