ICD-10 Code E70 – Disorders of aromatic amino-acid metabolism (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E70 – Disorders of aromatic amino-acid metabolism
What it is
E70 identifies inherited disorders that affect the body’s ability to break down aromatic amino acids, such as phenylalanine, tyrosine, and tryptophan. These are metabolic conditions that usually begin in infancy or childhood.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include developmental delay, feeding problems, neurologic symptoms, or abnormal odor, depending on the specific enzyme defect and severity.
When to use this code
Use E70 when the provider documents a disorder of aromatic amino-acid metabolism without naming a more specific diagnosis. It may also apply when the record confirms an inherited amino-acid metabolic defect but the exact subtype is not stated. Check documentation if a specific condition, such as phenylketonuria, is identified.
Do not use for
Do not use this code for acquired metabolic abnormalities, nonspecific abnormal laboratory results, or conditions outside aromatic amino-acid metabolism. If the chart names a specific disorder, code the more precise diagnosis instead.
Coding tip
Look for the exact inherited metabolic diagnosis in the record before assigning E70.