L04 – Acute lymphadenitis

ICD-10-CM 2027 diagnosis code · Infections of the skin and subcutaneous tissue

Non-billable header

ICD-10-CM code L04

Code: L04 (claims format: L04)
Description: Acute lymphadenitis
Billable: No – use a more specific code below
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 12. Diseases of the skin and subcutaneous tissue (L00-L99)
Block: L00-L08 Infections of the skin and subcutaneous tissue

Billable codes under L04

L04 is a header code and cannot be used on claims. Choose the most specific code:

L04.0 – Acute lymphadenitis of face, head and neckBillable
L04.1 – Acute lymphadenitis of trunkBillable
L04.2 – Acute lymphadenitis of upper limbBillable
L04.3 – Acute lymphadenitis of lower limbBillable
L04.8 – Acute lymphadenitis of other sitesBillable
L04.9 – Acute lymphadenitis, unspecifiedBillable

Notes for L04

Includes:

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

Excludes1 (not coded here):

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)

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

Block L00-L08

Excludes2 (not included here):

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.-)

Use additional code:

code (B95-B97) to identify infectious agent.

Frequently asked questions

What is ICD-10 code L04?

L04 is the ICD-10-CM code for acute lymphadenitis, in the block L00-L08 (Infections of the skin and subcutaneous tissue).

Is L04 a billable code?

No. L04 is a header code with more specific child codes; report one of the billable codes listed above.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.