2026 ICD-10-CM Diagnosis Code A48.2Nonpneumonic Legionnaires' disease [Pontiac fever]

ICD-10-CM CodesA00–B99A30-A49A48

ICD-10-CM A48.2
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A48.2 is a billable ICD-10-CM diagnosis code for nonpneumonic Legionnaires' disease [Pontiac fever]. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 867 through 869. Coders also document this condition as cutaneous involvement legionellosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections.

Code Identity

ICD-10-CM Code
A48.2
Billable Status
Yes — Valid for Submission
Code Describes
Nonpneumonic Legionnaires' disease [Pontiac fever]
Short Description
Nonpneumonic Legionnaires' disease [Pontiac fever]
Same as the full description in the CMS dataset.
Parent Code
Other bacterial diseases, not elsewhere classified

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA30-A49Other bacterial diseases
CategoryA48Other bacterial diseases, not elsewhere classified
This CodeA48.2Nonpneumonic Legionnaires' disease [Pontiac fever]

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cutaneous involvement legionellosis
  • Disseminated legionella infection
  • Extrapulmonary legionella infection
  • Legionella encephalopathy
  • Legionella infection
  • Pontiac fever

Index to Diseases and InjuriesGuidance

Clinical ClassificationClinical

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

CCSR INF003
Bacterial infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Pontiac Fever

    a self-limited, febrile illness without pneumonia that occurs in epidemics, and that is caused by legionella species.

Patient EducationClinical

Legionnaires' Disease

Legionnaires' disease is a serious type of pneumonia caused by Legionella bacteria. The disease got its name when a group of people at an American Legion convention became ill with this type of pneumonia.

The full article covers:

  • What is Legionnaires' Disease?
  • What causes Legionnaires' disease?
  • Who is more likely to develop Legionnaires' disease?
  • What are the symptoms of Legionnaires' disease?
  • What other problems can Legionnaires' disease cause?
  • How is Legionnaires' disease diagnosed?
  • What are the treatments for Legionnaires' disease?
  • Can Legionnaires' disease be prevented?

Read the full article at MedlinePlus

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

Convert A48.2 to ICD-9-CMHistory

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

ICD-9-CM
040.89 Bacterial diseases 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 A48.2Overview

What is the ICD-10 code for nonpneumonic Legionnaires' disease [Pontiac fever]?

The ICD-10-CM code for nonpneumonic Legionnaires' disease [Pontiac fever] is A48.2 (sometimes written as A482). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is A48.2 (Other bacterial diseases, not elsewhere classified) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report nonpneumonic Legionnaires' disease [Pontiac fever] on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does A48.2 group to?

When nonpneumonic Legionnaires' disease [Pontiac fever] is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 868, 869, with relative weights from 0.7297 to 2.0932 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of A48.2?

Under the General Equivalence Mappings, nonpneumonic Legionnaires' disease [Pontiac fever] converts to ICD-9-CM 040.89 (bacterial diseases NEC). The mapping is approximate, so confirm the match fits the documentation.