ICD-10 Code A04.9 – Bacterial intestinal infection, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A04.9 – Bacterial intestinal infection, unspecified
What it is
A04.9 identifies a bacterial infection of the intestine when the organism is not specified. Use it when documentation confirms a bacterial cause, but the chart does not name a more precise intestinal infection.
Clinical signs
Clinical features vary; refer to documentation. Commonly, intestinal bacterial infections present with diarrhea, abdominal cramps, nausea, vomiting, or other acute gastrointestinal symptoms.
When to use this code
Use A04.9 when the provider documents a bacterial intestinal infection without naming the organism or a more specific condition. It also fits cases where the record supports a bacterial etiology, but details are incomplete. If the organism is identified elsewhere, code that more specific diagnosis instead.
Do not use for
Do not use this code for viral, parasitic, or toxin-mediated gastrointestinal illness. Also avoid it when documentation supports a specific bacterial diagnosis that has its own code.
Coding tip
Check the note carefully for the named organism or a more precise intestinal infection before defaulting to A04.9.