ICD-10 Code L02.43 – Carbuncle of Limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L02.43 – Carbuncle of limb
What it is
L02.43 identifies a carbuncle on an arm or leg. It refers to a deeper skin infection with multiple connected boils in one limb.
Clinical signs
Typical findings include a painful, swollen, red area with pus drainage and surrounding inflammation. Clinical features vary; refer to documentation if the location or depth is unclear.
When to use this code
Use this code when the provider documents a carbuncle on the upper or lower extremity, such as the forearm, hand, thigh, or calf. It also fits when the record clearly states a limb site without a more specific subcategory. Check documentation if the note only says “abscess” or “boil.”
Do not use for
Do not use it for cellulitis, furuncle, or abscess without documentation of a carbuncle. If the site is not a limb, choose a more specific code.
Coding tip
Verify both the diagnosis and the limb location in the provider note before assigning L02.43.