ICD-10 code T86.41: Liver transplant rejection

Key takeaways

ICD-10 code T86.41 is the billable diagnosis code for liver transplant rejection, valid from October 1, 2025 through FY2026.

The physician’s note must contain the word rejection, because dysfunction or elevated enzymes will not support the code.

T86.41 covers rejection and T86.42 covers failure, and both can be reported when the record documents both.

Category T86 carries a use additional code note, so graft-versus-host disease under D89.81- is coded alongside T86.41.

Practice management software like Pabau links coded diagnoses to the clinical note and the claim, so nothing is retyped.

ICD-10 code T86.41: Definition and billable status

ICD-10 code T86.41 is the billable diagnosis code for liver transplant rejection. It took effect on October 1, 2025 and stays valid through the FY2026 coding year. The code sits in the CDC/NCHS ICD-10-CM system under parent category T86.4.

Chapter 19 of ICD-10-CM holds the code, inside the injury and poisoning block S00-T88. Coders and clinical documentation integrity (CDI) specialists reach for T86.41 when the recipient’s immune system attacks the transplanted liver.

That is a different event from graft failure, infection, or a biliary complication, and each of those has its own code. CMS lists T86.41 as a specific, billable code that needs no further subdivision.

Code details at a glance

The table below is the quick-reference summary for T86.41 as it appears in the FY2026 ICD-10-CM tabular list.

Clinical description of liver transplant rejection

Liver transplant rejection happens when the recipient’s immune system treats the transplanted liver as foreign tissue. It is an alloimmune process rather than an infection or a mechanical failure. Confirmation usually comes from a liver biopsy, which separates rejection from other causes of graft dysfunction.

The two main clinical subtypes are worth knowing, because the documentation language differs between them.

• Acute rejection: Occurs days to weeks after transplant. Liver enzymes rise quickly, biopsy shows cellular infiltration, and bile ducts are damaged. It is usually reversible with high-dose corticosteroids.
• Chronic rejection: Develops over months to years. It is associated with progressive bile duct loss and arteriopathy. It is often irreversible and may end in retransplantation.
• Hyperacute rejection: Rare and antibody-mediated. It occurs within hours of transplant and is typically catastrophic.

ICD-10-CM does not subdivide T86.41 by subtype. One code covers acute, chronic, and hyperacute rejection. The subtype still matters for the clinical record and for CDI queries, just not for code selection. Each transplanted organ has its own complication codes, so an infected lung graft takes T86.812 instead.

T86.41 in the ICD-10-CM hierarchy

The table below maps where T86.41 sits, from chapter down to the billable code. Sequencing rules follow from that placement.

Complication-of-care codes already describe what caused the complication, so no external cause code is required with T86.41. The code is also complete at five characters. Injury and poisoning codes such as T63.064D and T43.215A take a seventh character for the encounter type. Transplant complication codes in T86 do not.

Chapter 19 lets T86.41 stand as either a principal or a secondary diagnosis. When rejection is the reason for the encounter, it usually sequences first. That choice then drives MS-DRG assignment and payment.

Related codes under T86.4

The T86.4 subcategory holds five codes covering liver transplant complications. Picking the wrong sibling code is a frequent source of denied transplant claims.

One convention trips coders up more than any other here. Category T86 carries a use additional code note rather than an Excludes1. Graft-versus-host disease, or GVHD, sits under D89.81- and is reported alongside T86.41 when the record documents both.

GVHD runs in the opposite direction to rejection, with donor immune cells attacking the recipient. The same note also covers C80.2 and D47.Z1. Those pick up malignancy in a transplanted organ and post-transplant lymphoproliferative disorder.

T86.41 vs T86.42: rejection or failure

Rejection and failure are the two codes most often confused in liver transplant billing. CDI specialists query physicians whenever the note is ambiguous. The distinction is clinical rather than administrative.

When rejection progresses to failure, both codes can be reported if the physician documents both conditions. Neither code excludes the other. Accurate clinical record documentation at the point of care heads off later CDI queries and claim delays.

Coding guidelines for T86.41

The ICD-10-CM Official Guidelines for Coding and Reporting, Chapter 19, govern how transplant complication codes are applied. The rules below are the ones that decide whether a T86.41 claim survives review.

• Explicit physician documentation: The word rejection has to appear in the physician’s note. Coders cannot infer T86.41 from lab values, elevated enzymes, or ambiguous clinical language.
• Z94.4 as an additional code: Report Z94.4 whenever a patient with a prior liver transplant presents. It tells the payer the organ is a graft and supports accurate MS-DRG grouping.
• Sequencing: T86.41 is the principal diagnosis when rejection is the reason for admission. It drops to a secondary diagnosis when rejection is found during an admission for something else.
• Additional manifestation codes: Add codes for documented consequences of the rejection, such as bile duct damage or a named organ dysfunction.
• Use additional code note: Report D89.81- for graft-versus-host disease, plus C80.2 or D47.Z1, alongside T86.41 where the record supports them. None of these are excluded from T86.41.

Coders unsure about sequencing can check the AAPC ICD-10-CM lookup for crosswalk guidance and coding notes. Accurate coding inside a HIPAA-compliant workflow protects revenue and regulatory standing at the same time.

Documentation requirements for T86.41

Documentation failures are the main reason T86.41 claims are denied or downcoded. Check these elements before you assign the code.

The pitfall to watch: a pathology report can confirm rejection histologically while the attending physician’s note never uses the word. ICD-10-CM requires the physician’s own attestation.

A shared-care letter from primary care practices does not substitute for it either. Structured patient care documentation shortens the wait between the pathology result and the physician’s attestation.

When the note stays ambiguous, send a compliant query. Ask the physician to confirm whether the complication is rejection, failure, or an unspecified complication.

MS-DRG assignments for T86.41

MS-DRG grouping drives hospital payment on inpatient claims that carry T86.41. The assigned DRG depends on the full diagnosis profile, the procedure codes, and any complication or comorbidity reported.

T86.41 groups under liver transplant DRGs when a transplant procedure happened during the same admission. It groups under medical DRGs when the rejection is the only inpatient event.

Rejection without a concurrent transplant procedure commonly falls in DRG 441-443, disorders of liver except malignancy, cirrhosis, or alcoholic hepatitis. The exact DRG turns on CC and MCC presence.

Capturing Z94.4 alongside T86.41 keeps the transplant history on the claim. Claims management software links each coded diagnosis to the claim and the clinical note, so nothing is retyped from a lookup tool.

CC/MCC impact on DRG weight

T86.41 does not carry MCC status in most groupers, but comorbid conditions documented alongside it can. Acute kidney injury, sepsis, or respiratory failure coded as secondary diagnoses can move the claim to a higher-weighted DRG.

Audit every secondary diagnosis before submission. Check DRG numbers against the current CMS MS-DRG v43 definitions manual, because the values change with each fiscal year update.

Wording that maps to T86.41

The FY2026 tabular list carries no notes at all under T86.41. Two alphabetic index paths lead to the code. One runs from Complications, transplant, liver, rejection. The other runs from Rejection, transplant, liver.

Physicians write the same finding several ways. The phrasings below are plain-language equivalents rather than official inclusion terms, and each one should still send a coder to T86.41.

• Liver transplant rejection
• Hepatic allograft rejection
• Liver graft rejection
• Transplanted liver rejection
• Acute rejection of a liver transplant
• Chronic rejection of a liver transplant

None of these wordings change the code. All of them resolve to T86.41 once the physician has used the word rejection. Coders relying on EHR integration to auto-suggest codes should confirm each phrasing maps correctly in their system.

Some phrases do not map at all. Liver dysfunction post-transplant, abnormal liver function tests after transplant, and graft dysfunction all need physician clarification before a code is assigned.

How Pabau keeps transplant coding tied to the documentation

Coding a transplant complication usually spans three systems. The EMR holds the note, a lookup tool supplies the code, and a billing platform files the claim. Every handoff is a chance to mistype a code or lose the physician’s exact wording.

Pabau, an all-in-one practice management system, keeps those steps in one place. Pabau Scribe, our AI scribe, drafts the clinical note from the consultation. Digital intake forms capture the transplant history before the patient arrives.

Note templates can prompt for the specificity the code needs, which is what separates T86.41 from T86.42 at the point of writing. The coded diagnosis then moves to the claim without a copy-and-paste step in between.

Transplant recipients stay under review for years, often with metabolic complications from immunosuppression. Metabolic health practices running that long-term follow-up gain the most when the record and the claim sit in one system.

Keep coded diagnoses tied to the note

Pabau links each coded diagnosis, including T86.41, to the clinical note and the claim it belongs to. Your coders stop retyping between a lookup tool and a claim form.

Book a demo

Conclusion

T86.41 turns on one word in the chart. If the attending physician writes rejection, the code is supported. If the note stops at dysfunction, a query is the only route forward.

The rest is habit. Query early rather than after the denial. Keep Z94.4 on every post-transplant encounter, and code GVHD alongside T86.41 rather than choosing between the two.

Fixing the wording upstream saves the resubmission cycle downstream. Book a demo to see how Pabau keeps coded diagnoses tied to the clinical record and the claim.

Continue your research

Coding a complication in another transplanted organ? T86.812 walks through the documentation triggers and sibling codes for lung graft infection.

Need the seventh-character rules in Chapter 19? T43.215A shows how encounter characters work on an adverse effect code.

Reporting a subsequent encounter for a toxic effect? T63.064D covers sequencing and documentation for follow-up visits after venom exposure.

Bringing new coders up to speed on your system? EHR training sets out how to get a team confident with clinical software quickly.

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