J4A.0 ICD-10-CM Code: Restrictive allograft syndrome

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for J4A.0 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on J4A.0 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for J4A.0

MedCoder structured workflow — derived from this code’s own official record

Before you code J4A.0

1. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with J4A.0. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

   See the official tabular notes

Choose the right path

1. Does the documentation support a condition named in J4A.0’s Excludes1 note?
   Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
   No → Continue.

   ReviewJ68.0

2. Is the underlying (etiologic) condition the Code First note names documented?
   Yes → Sequence the underlying condition first, then J4A.0.
   No → Continue; do not add an underlying condition the record does not document.

   ReviewT86.31, T86.810, T86.39, T86.818

Consider J4A.0. Then review the Code Also note, and confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement

Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).

Acuity

Acute or chronic as documented; when both are documented and separate codes exist, both are reported with the acute code first (Guidelines I.B.8).

The underlying (etiologic) condition

Named in the Code First note; sequenced before this code when documented (Guidelines I.A.13).

Official instructions as workflow

• Excludes1 — check before selecting J4A.0(1 note)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with J4A.0: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareJ68.0

  See the official tabular notes · Guidelines I.A.12.a

• Excludes2 — not part of J4A.0(1 note)

  Coding workflow: The conditions named in this note are not included in J4A.0. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareE84

  See the official tabular notes · Guidelines I.A.12.b

• Code First — sequencing check(5 notes)

  Coding workflow: Check whether the underlying or etiologic condition the note names is documented. When it is, sequence it before J4A.0. Do not add an underlying condition the record does not document.

  ReviewT86.31, T86.810, T86.39, T86.818

  See the official tabular notes · Guidelines I.A.13

• Code Also — related condition(2 notes)

  Coding workflow: Review the related condition when both are documented and the instruction applies. A Code Also note does not fix sequencing; the order follows the circumstances of the encounter.

  ReviewJ44.81

  See the official tabular notes · Guidelines I.A.17

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Indexed Clinical Terms (2)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

• Dysfunction, chronic, lung allograft, mixed
• Syndrome, restrictive allograft

Don’t confuse J4A.0 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of J4A.0 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

• J68.0— Excludes1 conflict (Excludes1 — generally not reported together)

  Not coded here — the tabular list excludes this pair for the same encounter.

  Not reported together with this code, except where the two conditions are documented as unrelated.

  What moves you there: Documentation of bronchitis due to chemicals, gases, fumes and vapors moves the case to J68.0; the two are not reported together unless documented as unrelated.

  Full comparison: J4A.0 vs J68.0 →

• J4A.9— Specificity relationship (Review)

  Overlapping diagnoses in the same category.

  Overlapping codes in the same category — the documentation decides which is the more specific fit.

  What moves you there: A record that documents no more than “Chronic lung allograft dysfunction, unspecified” takes J4A.9; specificity in the record moves it back here.

  Full comparison: J4A.0 vs J4A.9 →

• E84— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of cystic fibrosis adds E84; it is not part of this code and both may be reported when both are documented.

  Full comparison: J4A.0 vs E84 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Decision Points

The directives on this code's own record, as a pre-claim checklist.

1. Sequencing: 5 Code First instructions — the underlying condition is sequenced before this code when present. See the Code First notes
2. 2 Code Also notes — a second code may apply; the guidelines leave its sequencing to the circumstances of the encounter. See the Code Also notes
3. 1 Excludes1 entry — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
4. 1 Excludes2 entry — those conditions are not part of this code and may be reported additionally when documented. See the Excludes2 notes

Checklist rows are derived from this code's own official directives; the wording of each check is MedCoder editorial. The official notes themselves are in the sections each row links to.

Verify Before Coding

• No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name J4A.0 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Code Also instruction: J44.81 — Bronchiolitis obliterans and bronchiolitis obliterans syndrome (via J4A.-).

These codes suggest coding this condition alongside when both are present.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 3 MS-DRGs: DRG 190 (MDC 04), DRG 191 (MDC 04), DRG 192 (MDC 04).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):INJ036 — Complication of transplanted organs or tissue, initial encounter (default); RSP016 — Other specified and unspecified lower respiratory disease.

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Lung Transplant Status/Complications) for risk-adjusted payment.

J4A.8 — Other chronic lung allograft dysfunction, J4A.9 — Chronic lung allograft dysfunction, unspecified, T86.30 — Unspecified complication of heart-lung transplant, T86.31 — Heart-lung transplant rejection, T86.32 — Heart-lung transplant failure, T86.33 — Heart-lung transplant infection, T86.39 — Other complications of heart-lung transplant, T86.810 — Lung transplant rejection, T86.811 — Lung transplant failure, T86.812 — Lung transplant infection, T86.818 — Other complications of lung transplant, T86.819 — Unspecified complication of lung transplant, Z48.24 — Encounter for aftercare following lung transplant, Z48.280 — Encounter for aftercare following heart-lung transplant, Z94.2 — Lung transplant status, Z94.3 — Heart and lungs transplant status

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Cystic Fibrosis, Idiopathic Pulmonary Fibrosis and Lung Involvement in Systemic Sclerosis, Severe Persistent Asthma, Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Complication of transplanted organs or tissue, initial encounter, Other specified and unspecified lower respiratory disease).

B44.1 — Other pulmonary aspergillosis, B45.0 — Pulmonary cryptococcosis, B46.0 — Pulmonary mucormycosis, B67.1 — Echinococcus granulosus infection of lung, D89.810 — Acute graft-versus-host disease, D89.811 — Chronic graft-versus-host disease, D89.812 — Acute on chronic graft-versus-host disease, D89.813 — Graft-versus-host disease, unspecified, J18.2 — Hypostatic pneumonia, unspecified organism, J22 — Unspecified acute lower respiratory infection, J4A.8 — Other chronic lung allograft dysfunction, J4A.9 — Chronic lung allograft dysfunction, unspecified, J81.0 — Acute pulmonary edema, J81.1 — Chronic pulmonary edema, J82 — Pulmonary eosinophilia, not elsewhere classified, J82.81 — Chronic eosinophilic pneumonia, J82.82 — Acute eosinophilic pneumonia, J82.83 — Eosinophilic asthma, J82.89 — Other pulmonary eosinophilia, not elsewhere classified, J84.01 — Alveolar proteinosis, +155 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Dysfunction”; these codes share that main term but sit in a different category of the Tabular List.

I20.81 — Angina pectoris with coronary microvascular dysfunction (coronary microvascular, with, angina pectoris), I21.B — Myocardial infarction with coronary microvascular dysfunction (coronary microvascular, with, myocardial infarction), I24.81 — Acute coronary microvascular dysfunction (coronary microvascular, acute), I25.85 — Chronic coronary microvascular dysfunction (coronary microvascular), I27.841 — Fontan-associated lymphatic dysfunction (lymphatic, Fontan-associated), I49.5 — Sick sinus syndrome (sinoatrial node), I50.9 — Heart failure, unspecified (ventricular, with congestive heart failure), I51.81 — Takotsubo syndrome (left ventricular, following sudden emotional stress), I51.89 — Other ill-defined heart diseases (heart), I51.9 — Heart disease, unspecified (ventricular), K31.89 — Other diseases of stomach and duodenum (stomach), K31.9 — Disease of stomach and duodenum, unspecified (pylorus), K59.9 — Functional intestinal disorder, unspecified (colon), K76.89 — Other specified diseases of liver (liver), K82.8 — Other specified diseases of gallbladder (gallbladder), K94.03 — Colostomy malfunction (colostomy), K94.13 — Enterostomy malfunction (ileostomy), K94.23 — Gastrostomy malfunction (gastrostomy), M26.62 — Arthralgia of temporomandibular joint (temporomandibular, joint-pain syndrome), M26.69 — Other specified disorders of temporomandibular joint (temporomandibular), +113 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

HbA1c Test (Glycated Hemoglobin), Blood Glucose Test

Contextual Map

Every relationship of J4A.0 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run J4A.0 with this related code in Claim Check

Hierarchy

• J00-J99 — Chapter 10: Diseases of the Respiratory System (J00-J99) (J00-J99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Code Also

• J44.81 — Bronchiolitis obliterans and bronchiolitis obliterans syndrome[Code Also]: “, if applicable, for mixed chronic lung allograft dysfunction, bronchiolitis obliterans syndrome (J44.81)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code Also instructions

• J44.81 — Bronchiolitis obliterans and bronchiolitis obliterans syndrome[Code Also](via J4A.-): “chronic lung allograft dysfunction (J4A.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• INJ036 — Complication of transplanted organs or tissue, initial encounter[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)
• RSP016 — Other specified and unspecified lower respiratory disease[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

Risk adjustment (CMS-HCC)

• HCC 276 — Lung Transplant Status/Complications [CMS-HCC]: “Lung Transplant Status/Complications — supersedes HCC 277 (Cystic Fibrosis), HCC 278 (Idiopathic Pulmonary Fibrosis and Lung Involvement in Systemic Sclerosis), HCC 279 (Severe Persistent Asthma), HCC 280 (Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders)”— CMS-HCC V28 · 2026

MS-DRG Grouper

• DRG 190 — CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITH MCC[MS-DRG]: “CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITH MCC (MDC 04)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 191 — CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITH CC[MS-DRG]: “CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITH CC (MDC 04)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 192 — CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITHOUT CC/MCC[MS-DRG]: “CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITHOUT CC/MCC (MDC 04)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

• MDC 04 — Diseases and Disorders of the Respiratory System[MDC crossing]: “Diseases and Disorders of the Respiratory System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 3,998 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries

• Dysfunction, chronic, lung allograft, mixed[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Syndrome, restrictive allograft[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes

• J4A — Chronic lung allograft dysfunction[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J4A.8 — Other chronic lung allograft dysfunction[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J4A.9 — Chronic lung allograft dysfunction, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Change history

• FY2024 — Added to the code set[Change history]— CMS release files (code change ledger) · icd10cm-fy2024

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data

CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page

Claim edits Official source data

CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page

Inpatient payment groups Official source data

CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page

Risk adjustment Official source data

2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page

Change history and date-of-service validity Official source data

CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page

Comparisons, relationships and the contextual map MedCoder structured relationship

Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears

Summary and FAQ answers MedCoder explanation

Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Nearest Codes in This Family

Official ICD-10-CM classifications closest to J4A.0 in its code family, with their registry titles.

• J4A — Chronic lung allograft dysfunction
• J4A.8 — Other chronic lung allograft dysfunction
• J4A.9 — Chronic lung allograft dysfunction, unspecified

View all codes in the J4A family