ICD-10 Code E72.02 – Hartnup’s Disease (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E72.02 – Hartnup’s disease
What it is
E72.02 identifies Hartnup’s disease, an inherited disorder of amino acid transport. It affects absorption and reabsorption of neutral amino acids, especially tryptophan.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings include intermittent skin eruptions, neurologic symptoms, and episodes triggered by stress, illness, or poor nutrition.
When to use this code
Use E72.02 when the record specifically documents Hartnup’s disease or Hartnup disorder. It may also apply when the clinician confirms the inherited amino acid transport defect as the active diagnosis. If the note only mentions nonspecific rash or malabsorption, check documentation before coding.
Do not use for
Do not use this code for general nutritional deficiency, isolated dermatitis, or nonspecific amino acid abnormalities without a documented diagnosis. Check documentation if the condition is only suspected.
Coding tip
Code E72.02 only when the provider names Hartnup’s disease; otherwise, query for clarification.