ICD-10 Code A04.1 – Enterotoxigenic Escherichia coli infection (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code A04.1 – Enterotoxigenic Escherichia coli infection
What it is
A04.1 identifies infection caused by enterotoxigenic Escherichia coli, a diarrheagenic E. coli strain. Use it when the record specifically documents this organism as the cause of illness.
Clinical signs
Typical features include acute watery diarrhea, abdominal cramps, and possible nausea. Clinical features vary; refer to documentation for the organism identified and whether the illness is confirmed or suspected.
When to use this code
Use this code when the provider documents enterotoxigenic E. coli infection as the diagnosis. It may appear in travel-related gastroenteritis or other infectious diarrhea workups when the causative strain is named. Code only what is documented, and check whether the case is confirmed by testing or clinical assessment.
Do not use for
Do not use this code for unspecified diarrhea, generic E. coli infection, or other diarrheagenic E. coli types. Check documentation if the record does not clearly identify enterotoxigenic E. coli.
Coding tip
Confirm the exact organism name in the chart before assigning A04.1.