ICD-10 Code B77 – Ascariasis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B77 – Ascariasis
What it is
Ascariasis is an intestinal infection caused by the roundworm Ascaris. Use this code when the record documents ascariasis without a more specific site or complication.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings include abdominal discomfort, nausea, cough during larval migration, or passage of worms in stool.
When to use this code
Use B77 when the provider diagnoses ascariasis and does not specify a different helminth infection code. It also fits confirmed cases described as intestinal roundworm infection or Ascaris infection. If the note identifies a complication or another parasite, check documentation for a more specific code.
Do not use for
Do not use this code for nonspecific abdominal symptoms or suspected parasite exposure without a confirmed diagnosis. Do not code it for other helminth infections, such as hookworm or pinworm.
Coding tip
Confirm the organism name in the record; “roundworm” alone may be too vague, so check documentation before assigning B77.