2026 ICD-10-CM Diagnosis Code J85.1Abscess of lung with pneumonia

ICD-10-CM CodesJ00–J99J85-J86J85

ICD-10-CM J85.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

J85.1 is a billable ICD-10-CM diagnosis code for abscess of lung with pneumonia. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 177 through 179. Coders also document this condition as abscess of lung. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Pneumonia (except that caused by tuberculosis).

Code Identity

ICD-10-CM Code
J85.1
Billable Status
Yes — Valid for Submission
Code Describes
Abscess of lung with pneumonia
Short Description
Abscess of lung with pneumonia
Same as the full description in the CMS dataset.
Parent Code
Abscess of lung and mediastinum

Code Classification

ChapterJ00–J99Diseases of the respiratory system
SectionJ85-J86Suppurative and necrotic conditions of the lower respiratory tract
CategoryJ85Abscess of lung and mediastinum
This CodeJ85.1Abscess of lung with pneumonia

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abscess of lung
  • Abscess of lung with pneumonia
  • Confluent bronchopneumonia with abscess formation
  • Confluent pneumonia

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Code Also

  • the type of pneumonia

Index to Diseases and InjuriesGuidance

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Abscess(connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic)
      • lung (miliary) (putrid)
        • with pneumonia
    • Pneumonia(acute) (double) (migratory) (purulent) (septic) (unresolved)
      • with
        • lung abscess

Clinical ClassificationClinical

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

CCSR RSP002
Pneumonia (except that caused by tuberculosis)
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Abscess

An abscess is a pocket of pus. You can get an abscess almost anywhere in your body. When an area of your body becomes infected, your body's immune system tries to fight the infection. White blood cells go to the infected area, collect within the damaged tissue, and cause inflammation. During this process, pus forms.

Read the full article at MedlinePlus

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

Convert J85.1 to ICD-9-CMHistory

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

ICD-9-CM
513.0 Abscess of lung
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About J85.1Overview

Is J85.1 (Abscess of lung and mediastinum) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report abscess of lung with pneumonia on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does J85.1 group to?

When abscess of lung with pneumonia is the principal diagnosis on an inpatient stay, it groups to MS-DRG 177, 178, 179, with relative weights from 0.7550 to 1.5627 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of J85.1?

Under the General Equivalence Mappings, abscess of lung with pneumonia converts to ICD-9-CM 513.0 (abscess of lung). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.