2027 ICD-10-CM Diagnosis Code J84.82Adult pulmonary Langerhans cell histiocytosis

ICD-10-CM Codes›J00–J99›J80-J84›J84

ICD-10-CM J84.82
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

J84.82 is a billable ICD-10-CM diagnosis code for adult pulmonary Langerhans cell histiocytosis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 196 through 198. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 90 closely related codes. The code is restricted by the Medicare Code Editor to adult patients (age 15 through 124). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified lower respiratory disease.

For Medicare Advantage risk adjustment, J84.82 maps to CMS-HCC Category 280 (Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders) under the V28 model, adding a risk factor of about 0.319 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
J84.82
Billable Status
Yes — Valid for Submission
Code Describes
Adult pulmonary Langerhans cell histiocytosis
Short Description
Adult pulmonary Langerhans cell histiocytosis
Same as the full description in the CMS dataset.
Parent Code
J84.8
Other specified interstitial pulmonary diseases

Code Classification

ChapterJ00–J99Diseases of the respiratory system
SectionJ80-J84Other respiratory diseases principally affecting the interstitium
CategoryJ84Other interstitial pulmonary diseases
This CodeJ84.82Adult pulmonary Langerhans cell histiocytosis

Code EditsBilling

Medicare Code Editor checks that affect claim validity for J84.82.

Adult diagnoses
The Medicare Code Editor detects inconsistencies in adult cases by checking a patient's age and any diagnosis on the patient's record. The adult code edits apply to patients age range is 15–124 years inclusive (e.g., senile delirium, mature cataract).

Medicare Risk Adjustment (HCC)Billing

J84.82 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 280— Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders
Payment HCC · PY 2027 one of 79 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.319
community, non-dual, aged · ranges 0.209–0.390 across segments
Hierarchy
Superseded by HCC 276, HCC 277, HCC 278, and HCC 279
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 112
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 112 · ESRD (V21): HCC 112 · ESRD (V24): HCC 112
ESRD V21 weights: 0.066 dialysis, 0.281–0.299 functioning graft · ESRD V24 weights: 0.058 dialysis, 0.080–0.256 functioning graft
Part D (RxHCC)
RxHCC 227 — Pulmonary Fibrosis, Except Idiopathic
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Adult pulmonary Langerhans cell histiocytosis
  • Langerhans cell histiocytosis of lung

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to J84.82: its own notes plus those printed at J84.8, J84, and Chapter 10. A note printed at a category, block or chapter applies to every code under it.

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Adult PLCH

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From J84.8 Other specified interstitial pulmonary diseases applies to 8 codes
  • exogenous lipoid pneumonia (J69.1)
  • unspecified lipoid pneumonia (J69.1)
From J84 Other interstitial pulmonary diseases applies to 24 codes
  • drug-induced interstitial lung disorders (J70.2-J70.4)
  • interstitial emphysema (J98.2)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From J84 Other interstitial pulmonary diseases applies to 24 codes
  • lung diseases due to external agents (J60-J70)
From Chapter 10 (J00-J99) Diseases of the respiratory system applies to 366 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • smoke inhalation (T59.81-)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 10 (J00-J99) Diseases of the respiratory system applies to 366 codes
  • code, where applicable, to identify:
  • exposure to environmental tobacco smoke (Z77.22)
  • exposure to tobacco smoke in the perinatal period (P96.81)
  • history of tobacco dependence (Z87.891)
  • occupational exposure to environmental tobacco smoke (Z57.31)
  • tobacco dependence (F17.-)
  • tobacco use (Z72.0)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

From J84 Other interstitial pulmonary diseases applies to 24 codes
  • if applicable, associated condition

Notes

General instructions on how these codes are used.

From Chapter 10 (J00-J99) Diseases of the respiratory system applies to 366 codes
  • When a respiratory condition is described as occurring in more than one site and is not specifically indexed, it should be classified to the lower anatomic site (e.g. tracheobronchitis to bronchitis in J40).

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name J84.82, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming J84.82: they are not reported together with it, unless the two conditions are unrelated.

  • C96.0 Multifocal and multisystemic (disseminated) Langerhans-cell histiocytosis
    adult pulmonary Langerhans cell histiocytosis (J84.82)
  • E88.89 Other specified metabolic disorders
    adult pulmonary Langerhans cell histiocytosis (J84.82)

Code Also 1

These codes say J84.82 may also be needed to fully describe the condition. The note gives no sequencing direction.

  • I27.23 Pulmonary hypertension due to lung diseases and hypoxia
    interstitial lung disease (J84.-) names J84.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR RSP016
Other specified and unspecified lower respiratory disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Interstitial Lung Diseases

Interstitial lung disease is the name for a large group of diseases that inflame or scar the lungs. The inflammation and scarring make it hard to get enough oxygen. The scarring is called pulmonary fibrosis.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert J84.82 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
516.5 Adlt pul Langs cell hist
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About J84.82Overview

What is the ICD-10 code for adult pulmonary Langerhans cell histiocytosis?

The ICD-10-CM code for adult pulmonary Langerhans cell histiocytosis is J84.82 (sometimes written as J8482). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is J84.82 (Other specified interstitial pulmonary diseases) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report adult pulmonary Langerhans cell histiocytosis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does J84.82 group to?

When adult pulmonary Langerhans cell histiocytosis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 198, 197, 196, with relative weights from 0.7256 to 1.8335 depending on complications. Higher weights mean higher Medicare reimbursement.

Is J84.82 a CC or MCC?

CMS lists J84.82 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 90 closely related codes in its exclusion list.

Who can J84.82 be reported for?

The Medicare Code Editor checks adult pulmonary Langerhans cell histiocytosis against patient demographics: this code is intended for adult patients (age 15 through 124). Claims outside these limits are flagged as inconsistent.

What HCC is J84.82?

J84.82 (adult pulmonary Langerhans cell histiocytosis) maps to CMS-HCC Category 280 (Chronic Obstructive Pulmonary Disease, Interstitial Lung Disorders, and Other Chronic Lung Disorders), commonly written as HCC 280, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 112 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 227.

Does J84.82 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, J84.82 adds a risk adjustment factor of about 0.319 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.209 to 0.390 depending on the payment segment). A more severe related category (HCC 276, HCC 277, HCC 278, and HCC 279) supersedes it when both are reported. See the full factor table on the HCC 280 category page.