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ICD-10-CM 2027 diagnosis code

J4AChronic lung allograft dysfunction

Not billable — use a more specific code

J4A is a header code, so it can't be reported by itself. Choose one of the 3 more specific codes beneath it.

Code last changed in FY2024 (effective October 1, 2023). Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About J4A

J4A is the ICD-10-CM diagnosis code for chronic lung allograft dysfunction. It belongs to block J40-J4B (chronic lower respiratory diseases) and chapter 10 (diseases of the respiratory system). It is a header code, so it can't be reported by itself; one of its 3 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: J4A.0 (syndrome), J4A.8 (dysfunction) and J4A.9 (unspecified).

Code first , if applicable: heart-lung transplant rejection (T86.31), lung transplant rejection (T86.810), other complications of heart-lung transplant (T86.39) and other complications of lung transplant (T86.818).

It was added in FY2024, effective October 1, 2023.

Specific codes under J4A

Coding notes

Code firstSequence the underlying condition first
  • , 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)
Code alsoTwo codes may be needed; sequencing depends on circumstances
  • , if applicable, bronchiolitis obliterans syndrome (J44.81)

Notes that apply from higher levels

Instructions written at a parent level also apply to J4A.

Broader instructions also apply from J40-J4B Chronic lower respiratory diseases and Chapter 10: Diseases of the respiratory system.

Codes whose notes reference J4A

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2024 (effective 10/1/2023): Added
  • No changes since FY2024.

Common questions about J4A

Is J4A billable?

No. J4A is a header code. Report one of its more specific subcodes instead.