ICD-10 Code E70.89 – Other disorders of aromatic amino-acid metabolism (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code E70.89 – Other disorders of aromatic amino-acid metabolism
What it is
This code identifies inherited or acquired disorders affecting the breakdown of aromatic amino acids, such as phenylalanine, tyrosine, or tryptophan. Use it when the record specifies an aromatic amino-acid metabolism disorder but does not name a more specific condition.
Clinical signs
Clinical features vary; refer to documentation. Findings may include developmental delay, neurologic symptoms, feeding problems, or abnormal metabolic testing, depending on the specific disorder.
When to use this code
Use E70.89 when the clinician documents a nonspecific aromatic amino-acid metabolism disorder and the chart does not support a more exact diagnosis. It is also appropriate when the condition is confirmed but the subtype is not yet defined. Check documentation for the exact metabolic disorder named.
Do not use for
Do not use this code for a clearly identified disorder that has its own ICD-10-CM code, such as phenylketonuria or another specified amino-acid metabolism condition. Avoid it when documentation is vague and no metabolic disorder is confirmed.
Coding tip
Code the most specific metabolic diagnosis available, and use E70.89 only when the provider documents an unspecified aromatic amino-acid metabolism disorder.