ICD-10 Code L66.3 – Perifolliculitis capitis abscedens (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L66.3 – Perifolliculitis capitis abscedens
What it is
L66.3 identifies perifolliculitis capitis abscedens, a chronic inflammatory scalp disorder that damages hair follicles. It is commonly associated with scarring and permanent hair loss.
Clinical signs
Typical findings include painful scalp nodules, abscesses, draining sinuses, and patchy alopecia with scarring. Clinical features vary; refer to documentation.
When to use this code
Use L66.3 when the provider documents perifolliculitis capitis abscedens, also known as dissecting cellulitis of the scalp. Code it for confirmed visits where the diagnosis is established or being managed. If the note only describes a scalp abscess or folliculitis without this specific diagnosis, check documentation.
Do not use for
Do not use this code for nonscarring alopecia, simple folliculitis, or a generic scalp infection without documentation of perifolliculitis capitis abscedens. Check documentation if the terminology is unclear.
Coding tip
Confirm the exact provider wording, because this code is specific to a scarring follicular disorder, not any scalp inflammation.