2027 ICD-10-CM Diagnosis Code A48.2Nonpneumonic Legionnaires' disease [Pontiac fever]

ICD-10-CM Codes›A00–B99›A30-A49›A48

ICD-10-CM A48.2
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

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 2027 (October 1, 2026 through September 30, 2027) 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
A48
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

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to A48.2: its own notes plus those printed at A48 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Excludes1

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

From A48 Other bacterial diseases, not elsewhere classified applies to 8 codes

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 Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

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

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

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

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

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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

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, 2026 through September 30, 2027.

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, 2026 through September 30, 2027.

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, 869, 868, with relative weights from 0.6784 to 2.1855 depending on complications. Higher weights mean higher Medicare reimbursement.

Can A48.2 be reported with B47.1?

Not as a rule. The Excludes1 note at A48, which applies to A48.2, lists "actinomycetoma (B47.1)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

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.