ICD-10 Code L13.1 – Subcorneal Pustular Dermatitis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L13.1 – Subcorneal pustular dermatitis
What it is
L13.1 identifies subcorneal pustular dermatitis, a rare inflammatory skin disorder marked by superficial pustules in the upper layers of the epidermis. Use it when the diagnosis is documented as such.
Clinical signs
Typical findings include recurring flaccid pustules, often in annular or grouped patterns, with erythema and scaling. Clinical features vary; refer to documentation.
When to use this code
Use L13.1 when the provider specifically documents subcorneal pustular dermatitis or a synonymous diagnosis. It is appropriate for confirmed visits, consults, or problem-list entries tied to this condition. Check documentation if the note only describes a nonspecific pustular rash.
Do not use for
Do not use this code for pustular eruptions without a documented diagnosis of subcorneal pustular dermatitis. If the record instead names another bullous or pustular disorder, code the stated condition.
Coding tip
Confirm the exact dermatologic diagnosis in the assessment, not just the rash description.