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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

Restrictive allograft syndrome

See Tabular List: J4A.0

J4A, Chronic lung allograft dysfunction

J4A.0, Restrictive allograft syndrome

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

J4A.0

Restrictive allograft syndrome

Open the shareable code page for J4A.0→
billableHCC mapped

Includes

official source

Not listed for this effective period.

Excludes 1

official source

No Excludes 1 note is listed in this source payload.

Excludes 2

official source

No Excludes 2 note is listed in this source payload.

Code First

official source
  • , if applicable:
  • heart-lung transplant rejection (T86.31)
  • lung transplant rejection (T86.810)
  • other complications of heart-lung transplant (T86.39)
  • other complications of lung transplant (T86.818)

Use Additional

official source

Not listed for this effective period.

Code Also

official source
  • , if applicable, for mixed chronic lung allograft dysfunction, bronchiolitis obliterans syndrome (J44.81)
  • , if applicable, bronchiolitis obliterans syndrome (J44.81)

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

Restrictive allograft syndrome

See Tabular List: J4A.0

J4A, Chronic lung allograft dysfunction

J4A.0, Restrictive allograft syndrome

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

J4A.0

Restrictive allograft syndrome

Open the shareable code page for J4A.0→
billableHCC mapped

Includes

official source

Not listed for this effective period.

Excludes 1

official source

No Excludes 1 note is listed in this source payload.

Excludes 2

official source

No Excludes 2 note is listed in this source payload.

Code First

official source
  • , if applicable:
  • heart-lung transplant rejection (T86.31)
  • lung transplant rejection (T86.810)
  • other complications of heart-lung transplant (T86.39)
  • other complications of lung transplant (T86.818)

Use Additional

official source

Not listed for this effective period.

Code Also

official source
  • , if applicable, for mixed chronic lung allograft dysfunction, bronchiolitis obliterans syndrome (J44.81)
  • , if applicable, bronchiolitis obliterans syndrome (J44.81)

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 276 Lung Transplant Status/Complications (V28)HCC 186 Major Organ Transplant or Replacement Status (V24)HCC 396 Allograft Complications (RxHCC)HCC 186 Major Organ Transplant or Replacement Status (ESRD/PACE)HCC 158 HHS-HCC 158; HHS-HCC 2026 benefit year (HHS-HCC)

RAF Value

V28: RAF: 2.531V24: RAF: 0.832RxHCC: RAF: Not separately weightedESRD/PACE: RAF: 0.138HHS-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 276

Lung Transplant Status/Complications

RAF: 2.531

V24

HCC 186

Major Organ Transplant or Replacement Status

RAF: 0.832

RxHCC

RxHCC 396

Allograft Complications

RAF: Not separately weighted

ESRD/PACE

HCC 186

Major Organ Transplant or Replacement Status

RAF: 0.138

HHS-HCC

HCC 158

HHS-HCC 158; 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
J4A.0Billable

Restrictive allograft syndrome

CMS-HCC V28

HCC 276

RAF 2.531

CMS-HCC V24

HCC 186

RAF 0.832

RxHCC

RxHCC 396

RAF Not separately weighted

Reviewed by the HCC Buddy Coding TeamFY2026 Apr update

Code

J4A.0

V28 HCC

HCC 276

RAF

2.531

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