ICD-10 Code A03.9 – Shigellosis, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A03.9 – Shigellosis, unspecified
What it is
A03.9 identifies shigellosis when the record confirms infection with Shigella but does not specify the species or type. Use it for an unspecified intestinal infection caused by Shigella bacteria.
Clinical signs
Typical features include acute diarrhea, abdominal cramps, fever, and sometimes blood or mucus in stool. Clinical features vary; refer to documentation.
When to use this code
Use this code when the provider documents shigellosis without naming the Shigella organism or giving a more specific subtype. It also fits cases where the chart confirms Shigella infection, but details are incomplete. Check documentation if the record suggests a different infectious cause.
Do not use for
Do not use A03.9 when the organism is specified and a more exact shigellosis code applies. Also avoid it for other causes of infectious diarrhea or when shigellosis is only suspected.
Coding tip
Code to the highest documented specificity and query for the Shigella species if the note is unclear.