ICD-10 Code L04.3 – Acute lymphadenitis of lower limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L04.3 – Acute lymphadenitis of lower limb
What it is
L04.3 identifies acute inflammation of the lymph nodes in the lower limb. It usually reflects an infectious process causing tender, enlarged nodes in the groin or leg drainage areas.
Clinical signs
Typical findings include localized pain, swelling, and tenderness over affected lymph nodes, sometimes with overlying redness or warmth. Clinical features vary; refer to documentation.
When to use this code
Use L04.3 when the provider documents acute lymphadenitis involving the lower extremity or its drainage nodes. Code it when the record supports an acute inflammatory node process, often linked to a nearby skin or soft tissue infection. Check documentation if the site is unclear.
Do not use for
Do not use this code for chronic lymph node enlargement, generalized lymphadenopathy, or nonspecific swollen nodes without an acute inflammatory diagnosis. Check documentation for the exact anatomic site.
Coding tip
Confirm that the note states both acuity and lower-limb location before assigning L04.3.