ICD-10 Code L04.2 – Acute lymphadenitis of upper limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L04.2 – Acute lymphadenitis of upper limb
What it is
L04.2 identifies acute inflammation of lymph nodes in the upper limb region. Use it when the record states acute lymphadenitis affecting arm or shoulder-area nodes, not a chronic or generalized process.
Clinical signs
Typical findings include tender, enlarged lymph nodes with local swelling and pain. Clinical features vary; refer to documentation for the exact site, laterality, and any associated skin or soft tissue source.
When to use this code
Use L04.2 when the provider documents acute lymphadenitis limited to the upper limb. It may appear after a nearby infection, wound, or other local inflammatory source, but the lymph node diagnosis must be stated clearly.
If the note only describes an arm infection without lymph node involvement, code the documented condition instead. Check documentation when the site is unclear or when the record suggests a broader lymphatic infection.
Do not use for
Do not use this code for chronic lymphadenitis, generalized lymphadenitis, or lymph node enlargement without acute inflammation. Do not assign it when the upper-limb location is not documented.
Coding tip
Confirm that “acute lymphadenitis” and the upper-limb site are both documented before assigning L04.2.