J84.2 ICD-10-CM Code: Lymphoid interstitial pneumonia

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for J84.2 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 J84.2 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for J84.2

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

Before you code J84.2

1. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with J84.2. 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 J84.2’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.

   ReviewJ98.2

Consider J84.2. 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).

Official instructions as workflow

• Excludes1 — check before selecting J84.2(2 notes)

  Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with J84.2: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

  CompareJ98.2

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

• Excludes2 — not part of J84.2(1 note)

  Coding workflow: The conditions named in this note are not included in J84.2. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

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

• Code Also — related condition(1 note)

  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.

  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 (4)

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.

• Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved), interstitial, lymphoid
• Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved), lymphoid interstitial
• Pneumonitis (acute) (primary), interstitial (chronic), lymphoid
• Pneumonitis (acute) (primary), lymphoid, interstitial

Don’t confuse J84.2 with…

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

The codes most likely to be picked instead of J84.2 — 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.

• J70.2— 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 drug-induced interstitial lung disorders moves the case to J70.2; the two are not reported together unless documented as unrelated.

  Full comparison: J84.2 vs J70.2 →

• J70.4— 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 drug-induced interstitial lung disorders moves the case to J70.4; the two are not reported together unless documented as unrelated.

  Full comparison: J84.2 vs J70.4 →

• J98.2— 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 interstitial emphysema moves the case to J98.2; the two are not reported together unless documented as unrelated.

  Full comparison: J84.2 vs J98.2 →

• J84.9— 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 “Interstitial pulmonary disease, unspecified” takes J84.9; specificity in the record moves it back here.

  Full comparison: J84.2 vs J84.9 →

• J60— 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 lung diseases due to external agents adds J60; it is not part of this code and both may be reported when both are documented.

  Full comparison: J84.2 vs J60 →

• J70— 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 lung diseases due to external agents adds J70; it is not part of this code and both may be reported when both are documented.

  Full comparison: J84.2 vs J70 →

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. 1 Code Also note — a second code may apply; the guidelines leave its sequencing to the circumstances of the encounter. See the Code Also notes
2. 2 Excludes1 entries — codes named there are generally not reported together with this code (Guidelines I.A.12.a). See the Excludes1 notes
3. 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

• CC as a secondary diagnosis (FY2026). Can raise the stay's MS-DRG severity tier.

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 J84.2 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 5 Excludes1 notes: J70.2 — Acute drug-induced interstitial lung disorders, J70.3 — Chronic drug-induced interstitial lung disorders, J70.4 — Drug-induced interstitial lung disorders, unspecified, J84.11 — Idiopathic interstitial pneumonia, J84.89 — Other specified interstitial pulmonary diseases.

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 1 Code Also instruction: I27.23 — Pulmonary hypertension due to lung diseases and hypoxia (via J84.-).

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: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 90 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 3 MS-DRGs: DRG 196 (MDC 04), DRG 197 (MDC 04), DRG 198 (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):RSP016 — Other specified and unspecified lower respiratory disease (default).

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 clinical process (MS-DRG)

Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

J84.02 — Pulmonary alveolar microlithiasis, J84.09 — Other alveolar and parieto-alveolar conditions, J84.10 — Pulmonary fibrosis, unspecified, J84.111 — Idiopathic interstitial pneumonia, not otherwise specified, J84.112 — Idiopathic pulmonary fibrosis, J84.113 — Idiopathic non-specific interstitial pneumonitis, J84.114 — Acute interstitial pneumonitis, J84.115 — Respiratory bronchiolitis interstitial lung disease, J84.116 — Cryptogenic organizing pneumonia, J84.117 — Desquamative interstitial pneumonia, J84.81 — Lymphangioleiomyomatosis, J84.82 — Adult pulmonary Langerhans cell histiocytosis, J84.89 — Other specified interstitial pulmonary diseases, J84.9 — Interstitial pulmonary disease, unspecified, J98.4 — Other disorders of lung, J98.8 — Other specified respiratory disorders, J98.9 — Respiratory disorder, unspecified, N80.B1 — Endometriosis of pleura, N80.B2 — Endometriosis of lung, N80.B31 — Superficial endometriosis of diaphragm, +69 more

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders) for risk-adjusted payment.

J84.03 — Idiopathic pulmonary hemosiderosis, J84.09 — Other alveolar and parieto-alveolar conditions, J84.10 — Pulmonary fibrosis, unspecified, J84.111 — Idiopathic interstitial pneumonia, not otherwise specified, J84.113 — Idiopathic non-specific interstitial pneumonitis, J84.114 — Acute interstitial pneumonitis, J84.115 — Respiratory bronchiolitis interstitial lung disease, J84.116 — Cryptogenic organizing pneumonia, J84.117 — Desquamative interstitial pneumonia, J84.178 — Other interstitial pulmonary diseases with fibrosis in diseases classified elsewhere, J84.81 — Lymphangioleiomyomatosis, J84.82 — Adult pulmonary Langerhans cell histiocytosis, J84.89 — Other specified interstitial pulmonary diseases, J84.9 — Interstitial pulmonary disease, unspecified, J98.2 — Interstitial emphysema, J98.3 — Compensatory emphysema, J99 — Respiratory disorders in diseases classified elsewhere, M32.13 — Lung involvement in systemic lupus erythematosus, M33.01 — Juvenile dermatomyositis with respiratory involvement, M33.11 — Other dermatomyositis with respiratory involvement, +58 more

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.

Lung Transplant Status/Complications, Cystic Fibrosis, Idiopathic Pulmonary Fibrosis and Lung Involvement in Systemic Sclerosis, Severe Persistent Asthma

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Other specified and unspecified lower respiratory disease).

J84.111 — Idiopathic interstitial pneumonia, not otherwise specified, J84.112 — Idiopathic pulmonary fibrosis, J84.113 — Idiopathic non-specific interstitial pneumonitis, J84.114 — Acute interstitial pneumonitis, J84.115 — Respiratory bronchiolitis interstitial lung disease, J84.116 — Cryptogenic organizing pneumonia, J84.117 — Desquamative interstitial pneumonia, J84.17 — Other interstitial pulmonary diseases with fibrosis in diseases classified elsewhere, J84.170 — Interstitial lung disease with progressive fibrotic phenotype in diseases classified elsewhere, J84.178 — Other interstitial pulmonary diseases with fibrosis in diseases classified elsewhere, J84.81 — Lymphangioleiomyomatosis, J84.82 — Adult pulmonary Langerhans cell histiocytosis, J84.83 — Surfactant mutations of the lung, J84.841 — Neuroendocrine cell hyperplasia of infancy, J84.842 — Pulmonary interstitial glycogenosis, J84.843 — Alveolar capillary dysplasia with vein misalignment, J84.848 — Other interstitial lung diseases of childhood, J84.89 — Other specified interstitial pulmonary diseases, J84.9 — Interstitial pulmonary disease, unspecified, J85.2 — Abscess of lung without pneumonia, +59 more

Same Index main term, other category

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

J69.0 — Pneumonitis due to inhalation of food and vomit (aspiration), J69.1 — Pneumonitis due to inhalation of oils and essences (lipid, lipoid), J69.8 — Pneumonitis due to inhalation of other solids and liquids (due to, detergent), J70.0 — Acute pulmonary manifestations due to radiation (radiation), J70.2 — Acute drug-induced interstitial lung disorders (chemotherapy, acute), J70.3 — Chronic drug-induced interstitial lung disorders (chemotherapy, chronic), J70.4 — Drug-induced interstitial lung disorders, unspecified (chemotherapy), J82.81 — Chronic eosinophilic pneumonia (eosinophilic), J82.82 — Acute eosinophilic pneumonia (eosinophilic, acute), J82.89 — Other pulmonary eosinophilia, not elsewhere classified (allergic), J85.0 — Gangrene and necrosis of lung (necrotic), J85.1 — Abscess of lung with pneumonia (with, lung abscess), J95.4 — Chemical pneumonitis due to anesthesia (postoperative), J95.851 — Ventilator associated pneumonia (due to, ventilator), J95.89 — Other postprocedural complications and disorders of respiratory system, not elsewhere classified (resulting from a procedure), J98.4 — Other disorders of lung, O29.01 — Aspiration pneumonitis due to anesthesia during pregnancy (postanesthetic, in pregnancy), O74.0 — Aspiration pneumonitis due to anesthesia during labor and delivery (aspiration, obstetric), O89.01 — Aspiration pneumonitis due to anesthesia during the puerperium (postanesthetic, postpartum, puerperal), P23.0 — Congenital pneumonia due to viral agent (viral, virus, congenital), +93 more

Contextual Map

Every relationship of J84.2 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 J84.2 with these 6 related codes 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
• J80-J84 — Other respiratory diseases principally affecting the interstitium[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• J70.2 — Acute drug-induced interstitial lung disorders[Excludes1]: “lymphoid interstitial pneumonia (J84.2)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• J70.3 — Chronic drug-induced interstitial lung disorders[Excludes1]: “lymphoid interstitial pneumonia (J84.2)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• J70.4 — Drug-induced interstitial lung disorders, unspecified[Excludes1]: “lymphoid interstitial pneumonia (J84.2)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• J84.11 — Idiopathic interstitial pneumonia[Excludes1]: “lymphoid interstitial pneumonia (J84.2)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• J84.89 — Other specified interstitial pulmonary diseases[Excludes1]: “lymphoid interstitial pneumonia (J84.2)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code Also instructions

• I27.23 — Pulmonary hypertension due to lung diseases and hypoxia[Code Also](via J84.-): “interstitial lung disease (J84.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• RSP016 — Other specified and unspecified lower respiratory disease[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

Risk adjustment (CMS-HCC)

• HCC 280 — Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

• CC — Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (CC).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2026
• DRG 196 — INTERSTITIAL LUNG DISEASE WITH MCC[MS-DRG]: “INTERSTITIAL LUNG DISEASE WITH MCC (MDC 04)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 197 — INTERSTITIAL LUNG DISEASE WITH CC[MS-DRG]: “INTERSTITIAL LUNG DISEASE WITH CC (MDC 04)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 198 — INTERSTITIAL LUNG DISEASE WITHOUT CC/MCC[MS-DRG]: “INTERSTITIAL LUNG 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

• Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved), interstitial, lymphoid[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved), lymphoid interstitial[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pneumonitis (acute) (primary), interstitial (chronic), lymphoid[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Pneumonitis (acute) (primary), lymphoid, interstitial[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes (30)

• J84 — Other interstitial pulmonary diseases[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J84.0 — Alveolar and parieto-alveolar conditions[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J84.01 — Alveolar proteinosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J84.02 — Pulmonary alveolar microlithiasis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J84.03 — Idiopathic pulmonary hemosiderosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J84.09 — Other alveolar and parieto-alveolar conditions[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J84.1 — Other interstitial pulmonary diseases with fibrosis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• J84.10 — Pulmonary fibrosis, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• and 22 more

Change history

• FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

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 J84.2 in its code family, with their registry titles.

• J84.116 — Cryptogenic organizing pneumonia
• J84.117 — Desquamative interstitial pneumonia
• J84.17 — Other interstitial pulmonary diseases with fibrosis in diseases classified elsewhere
• J84.170 — Interstitial lung disease with progressive fibrotic phenotype in diseases classified elsewhere
• J84.178 — Other interstitial pulmonary diseases with fibrosis in diseases classified elsewhere
• J84.8 — Other specified interstitial pulmonary diseases
• J84.81 — Lymphangioleiomyomatosis
• J84.82 — Adult pulmonary Langerhans cell histiocytosis
• J84.83 — Surfactant mutations of the lung
• J84.84 — Other interstitial lung diseases of childhood

View all codes in the J84 family