ICD-10 Code A49 – Bacterial infection of unspecified site (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A49 – Bacterial infection of unspecified site
What it is
This code identifies a bacterial infection when the site is not specified in the record. Use it only when documentation confirms a bacterial infection but does not name the affected body site.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include signs of infection such as fever, localized pain, redness, swelling, or drainage, but the chart should support a bacterial cause.
When to use this code
Use A49 when the provider documents a bacterial infection and no more specific site code is available. It is appropriate when the source is unclear, not yet identified, or not documented in the encounter note.
If later records identify the site, you should code the more specific diagnosis instead. Check documentation for any associated organism or site-specific infection that may change code selection.
Do not use for
Do not use this code for viral, fungal, or parasitic infections, or when the infection site is documented more specifically. If the record only says “infection” without bacterial confirmation, check documentation.
Coding tip
Query for the infection site whenever possible, because a more specific code is usually preferred over an unspecified bacterial infection code.