ICD-10 Code E70.9 – Disorder of aromatic amino-acid metabolism, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E70.9 – Disorder of aromatic amino-acid metabolism, unspecified
What it is
E70.9 identifies an unspecified disorder affecting metabolism of aromatic amino acids. Use it when the record confirms a hereditary or metabolic problem in this pathway but does not name a specific disorder.
Clinical signs
Clinical features vary; refer to documentation. Affected patients may have developmental delay, neurologic symptoms, feeding problems, or abnormal screening results, but the chart must support a disorder of aromatic amino-acid metabolism.
When to use this code
Use E70.9 when the provider documents an aromatic amino-acid metabolism disorder without specifying phenylketonuria, tyrosinemia, or another named condition. It is also appropriate when the diagnosis is confirmed, but the exact subtype is not recorded.
Code from the documented diagnosis, not from a screening result alone. If the note gives a more specific metabolic disorder, choose that code instead of this unspecified category.
Do not use for
Do not use this code for isolated abnormal newborn screening, suspected disease, or a clearly named amino-acid disorder. Check documentation if the record points to a different inherited metabolic condition.
Coding tip
Query for the exact metabolic subtype whenever possible, because E70.9 is only for unspecified aromatic amino-acid metabolism disorders.