ICD-10 Code A03.1 – Shigellosis due to Shigella flexneri (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A03.1 – Shigellosis due to Shigella flexneri
What it is
A03.1 identifies shigellosis caused by Shigella flexneri. Use it for confirmed infection with this specific organism, which causes an acute intestinal illness.
Clinical signs
Typical findings include diarrhea, abdominal cramps, fever, and sometimes blood or mucus in stool. Clinical features vary; refer to documentation for organism confirmation and illness details.
When to use this code
Use this code when the record states Shigella flexneri as the cause of shigellosis, whether by culture, molecular testing, or clear provider documentation. It applies to symptomatic intestinal infection, not simple exposure or carrier status.
If the chart names only shigellosis without the species, check documentation before coding A03.1. Code the most specific organism documented and avoid guessing from travel history or symptoms alone.
Do not use for
Do not use this code for shigellosis due to another Shigella species or for unspecified shigellosis. Check documentation if the organism is not identified.
Coding tip
Code A03.1 only when Shigella flexneri is explicitly documented; otherwise, select the unspecified or different organism code supported by the record.