2026 ICD-10-CM Diagnosis Code J22Unspecified acute lower respiratory infection

ICD-10-CM Codes›J00–J99›J20-J22›J22

ICD-10-CM J22
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

J22 is a billable ICD-10-CM diagnosis code for unspecified acute lower respiratory infection. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 205 through 206. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified lower respiratory disease.

Code Identity

ICD-10-CM Code
J22
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified acute lower respiratory infection
Chapter
J20-J22
Other acute lower respiratory infections

Code Classification

ChapterJ00–J99Diseases of the respiratory system
SectionJ20-J22Other acute lower respiratory infections
CategoryJ22Unspecified acute lower respiratory infection
This CodeJ22Unspecified acute lower respiratory infection

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute lower respiratory infection caused by respiratory syncytial virus
  • Acute lower respiratory tract infection
  • Acute respiratory infections
  • Bacterial lower respiratory infection
  • COVID-19
  • Infection of lower respiratory tract and mediastinum
  • Infection of lower respiratory tract caused by SARS-CoV-2
  • Lower respiratory tract infection
  • Postoperative lower respiratory tract infection
  • Severe acute respiratory infection
  • Viral lower respiratory infection

Tabular List NotesGuidance

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

Inclusion Terms

  • Acute (lower) respiratory (tract) infection NOS

Type 1 Excludes

  • upper respiratory infection acute J06.9

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

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

    • Infection, infected, infective(opportunistic)
      • chest
    • Infection, infected, infective(opportunistic)
      • respiratory (tract) NEC
        • acute
    • Infection, infected, infective(opportunistic)
      • respiratory (tract) NEC
        • lower (acute)

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

Lung Diseases

When you breathe, your lungs take in oxygen from the air and deliver it to the bloodstream. The cells in your body need oxygen to work and grow. During a normal day, you breathe nearly 25,000 times. People with lung disease have difficulty breathing. Millions of people in the U.S. have lung disease.

Read the full article at MedlinePlus

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

Convert J22 to ICD-9-CMHistory

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

ICD-9-CM
519.8 Resp system disease NEC
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 J22Overview

Is J22 (Unspecified acute lower respiratory infection) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report unspecified acute lower respiratory infection on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does J22 group to?

When unspecified acute lower respiratory infection is the principal diagnosis on an inpatient stay, it groups to MS-DRG 205, 206, with relative weights from 0.9411 to 1.8310 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of J22?

Under the General Equivalence Mappings, unspecified acute lower respiratory infection converts to ICD-9-CM 519.8 (resp system disease NEC). 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.