2027 ICD-10-CM Diagnosis Code L04.0Acute lymphadenitis of face, head and neck

ICD-10-CM Codes›L00–L99›L00-L08›L04

ICD-10-CM L04.0
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

L04.0 is a billable ICD-10-CM diagnosis code for acute lymphadenitis of face, head and neck. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 791, 793, 814 through 816. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Skin and subcutaneous tissue infections.

Code Identity

ICD-10-CM Code
L04.0
Billable Status
Yes — Valid for Submission
Code Describes
Acute lymphadenitis of face, head and neck
Short Description
Acute lymphadenitis of face, head and neck
Same as the full description in the CMS dataset.
Parent Code
L04
Acute lymphadenitis

Code Classification

ChapterL00–L99Diseases of the skin and subcutaneous tissue
SectionL00-L08Infections of the skin and subcutaneous tissue
CategoryL04Acute lymphadenitis
This CodeL04.0Acute lymphadenitis of face, head and neck

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute cervical lymphadenitis
  • Acute lymphadenitis of face
  • Acute lymphadenitis of face, head and neck
  • Acute lymphadenitis of head
  • Acute occipital lymphadenitis
  • Cervical lymph node abscess
  • Cervical lymphadenitis
  • Facial lymphadenopathy
  • Head and neck lymphadenopathy
  • Lymph node abscess
  • Occipital lymphadenopathy
  • Suppurative cervical lymphadenitis
  • Suppurative lymphadenitis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to L04.0: its own notes plus those printed at L04, block L00-L08, and Chapter 12. 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 L04 Acute lymphadenitis applies to 6 codes
  • abscess (acute) of lymph nodes, except mesenteric
  • acute lymphadenitis, except mesenteric

Excludes1

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

From L04 Acute lymphadenitis applies to 6 codes
  • 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)

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 Block L00-L08 Infections of the skin and subcutaneous tissue applies to 159 codes
  • hordeolum (H00.0)
  • infective dermatitis (L30.3)
  • local infections of skin classified in Chapter 1
  • lupus panniculitis (L93.2)
  • panniculitis NOS (M79.3)
  • panniculitis of neck and back (M54.0-)
  • Perlèche NOS (K13.0)
  • Perlèche due to candidiasis (B37.0)
  • Perlèche due to riboflavin deficiency (E53.0)
  • pyogenic granuloma (L98.0)
  • relapsing panniculitis [Weber-Christian] (M35.6)
  • viral warts (B07.-)
  • zoster (B02.-)
From Chapter 12 (L00-L99) Diseases of the skin and subcutaneous tissue applies to 1,001 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • lipomelanotic reticulosis (I89.8)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • systemic connective tissue disorders (M30-M36)
  • viral warts (B07.-)

Use Additional Code

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

From Block L00-L08 Infections of the skin and subcutaneous tissue applies to 159 codes
  • code (B95-B97) to identify infectious agent.

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name L04.0, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming L04.0: they are not reported together with it, unless the two conditions are unrelated.

  • I88 Nonspecific lymphadenitis
    acute lymphadenitis, except mesenteric (L04.-) names L04.-, which includes this code
  • R59 Enlarged lymph nodes
    acute lymphadenitis (L04.-) names L04.-, which includes this code

Excludes2 1

These codes carry an Excludes2 note naming L04.0: its condition is not part of those codes, and both may be reported when the patient has both.

  • D75 Other and unspecified diseases of blood and blood-forming organs
    acute lymphadenitis (L04.-) names L04.-, which includes this code

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 SKN001
Skin and subcutaneous tissue infections
Default principal diagnosis: inpatient Yes · outpatient Yes

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.

Convert L04.0 to ICD-9-CMHistory

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

ICD-9-CM
683 Acute lymphadenitis
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 L04.0Overview

What is the ICD-10 code for acute lymphadenitis of face, head and neck?

The ICD-10-CM code for acute lymphadenitis of face, head and neck is L04.0 (sometimes written as L040). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is L04.0 (Acute lymphadenitis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report acute lymphadenitis of face, head and neck on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does L04.0 group to?

When acute lymphadenitis of face, head and neck is the principal diagnosis on an inpatient stay, it groups to MS-DRG 816, 793, 791, 814, 815, with relative weights from 0.7378 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.

Can L04.0 be reported with I88.1?

Not as a rule. The Excludes1 note at L04, which applies to L04.0, lists "chronic or subacute lymphadenitis, except mesenteric (I88.1)". 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 L04.0?

Under the General Equivalence Mappings, acute lymphadenitis of face, head and neck converts to ICD-9-CM 683 (acute lymphadenitis). The mapping is approximate, so confirm the match fits the documentation.