2026 ICD-10-CM Diagnosis Code L04Acute lymphadenitis

ICD-10-CM Codes›L00–L99›L00-L08›L04

ICD-10-CM L04
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

L04 is a non-billable ICD-10-CM category code for acute lymphadenitis, so it cannot be submitted on claims. Use a more specific code from this category instead, such as L04.0, L04.1, L04.2, and L04.3.

Code Identity

ICD-10-CM Code
L04
Billable Status
No — Non-Billable Category
Code Describes
Acute lymphadenitis
Chapter
L00-L08
Infections of the skin and subcutaneous tissue

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL00-L08Infections of the skin and subcutaneous tissue
CategoryL04Acute lymphadenitis
This CodeL04Acute lymphadenitis

Specific Coding for Acute lymphadenitisOverview

Non-specific codes like L04 require more characters. Use one of these billable codes instead:

  • Use L04.0 for Acute lymphadenitis of face, head and neck

  • Use L04.1 for Acute lymphadenitis of trunk

  • Use L04.2 for Acute lymphadenitis of upper limb

  • Use L04.3 for Acute lymphadenitis of lower limb

  • Use L04.8 for Acute lymphadenitis of other sites

  • Use L04.9 for Acute lymphadenitis, unspecified

Tabular List NotesGuidance

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

Includes

  • abscess (acute) of lymph nodes, except mesenteric
  • acute lymphadenitis, except mesenteric

Type 1 Excludes

  • chronic or subacute lymphadenitis, except mesenteric I88.1
  • enlarged lymph nodes R59
  • human immunodeficiency virus HIV disease resulting in generalized lymphadenopathy B20
  • lymphadenitis NOS I88.9
  • nonspecific mesenteric lymphadenitis I88.0

Clinical InformationClinical

  • Acute Lymphadenitis

    acute inflammation of the lymph nodes.

Patient EducationClinical

Lymphatic Diseases

The lymphatic system is a network of tissues and organs. It is made up of:

Read the full article at MedlinePlus

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

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 L04Overview

Is L04 (Acute lymphadenitis) a billable code?

No. This is a category header that groups the codes for acute lymphadenitis, and headers cannot be submitted on claims. Claims for acute lymphadenitis need a more specific code from this category, such as L04.0, L04.1, and L04.2.