ICD-10-CM 2027
ICD-10 code for transplant rejection
Unspecified transplanted organ and tissue rejection
From the official ICD-10-CM alphabetic index entry “Rejection › transplant”. Page updated September 29, 2026.
About coding transplant rejection
The ICD-10-CM code for transplant rejection is T86.91 (Unspecified transplanted organ and tissue rejection). The official index lists 15 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on T86.91.
Within T86.9, choose T86.91 (Unspecified transplanted organ and tissue rejection) only when documentation doesn't support a more specific option: unspecified complication of unspecified transplanted organ and tissue (T86.90), unspecified transplanted organ and tissue failure (T86.92), unspecified transplanted organ and tissue infection (T86.93) and other complications of unspecified transplanted organ and tissue (T86.99).
Use an additional code to identify other transplant complications, such as: graft-versus-host disease (D89.81-), malignancy associated with organ transplant (C80.2) and post-transplant lymphoproliferative disorders (PTLD) (D47.Z1).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
More specific transplant rejection codes (official index)
- bone T86.830 — Bone graft rejection
- marrow T86.01 — Bone marrow transplant rejection
- cornea T86.840 — Corneal transplant rejection
- heart T86.21 — Heart transplant rejection
- with lung (s) T86.31 — Heart-lung transplant rejection
- intestine T86.850 — Intestine transplant rejection
- kidney T86.11 — Kidney transplant rejection
- liver T86.41 — Liver transplant rejection
- lung (s) T86.810 — Lung transplant rejection
- with heart T86.31 — Heart-lung transplant rejection
- organ (immune or nonimmune cause) T86.91 — Unspecified transplanted organ and tissue rejection
- pancreas T86.890 — Other transplanted tissue rejection
- skin (allograft) (autograft) T86.820 — Skin graft (allograft) rejection
- specified NEC T86.890 — Other transplanted tissue rejection
- stem cell (peripheral blood) (umbilical cord) T86.5 — Complications of stem cell transplant
Common questions about transplant rejection ICD-10 codes
What is the ICD-10 code for transplant rejection?
- T86.91 — Unspecified transplanted organ and tissue rejection. More specific codes apply when the documentation supports them: T86.830, T86.01, T86.840, T86.21 and others below.
What is the ICD-10 code for bone transplant rejection?
- T86.830 — Bone graft rejection.
What is the ICD-10 code for cornea transplant rejection?
- T86.840 — Corneal transplant rejection (header code; choose a more specific subcode).
What is the ICD-10 code for heart transplant rejection?
- T86.21 — Heart transplant rejection.
What is the ICD-10 code for intestine transplant rejection?
- T86.850 — Intestine transplant rejection.
What is the ICD-10 code for kidney transplant rejection?
- T86.11 — Kidney transplant rejection.
What is the ICD-10 code for liver transplant rejection?
- T86.41 — Liver transplant rejection.
Is T86.91 billable?
- Yes. T86.91 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can T86.91 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict T86.91 as a principal diagnosis.
Is T86.91 a CC or MCC?
- T86.91 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.