ICD-10 Code B83.9 – Helminthiasis, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B83.9 – Helminthiasis, unspecified
What it is
B83.9 identifies a helminth infection when the specific worm type is not documented. Use it for an unspecified parasitic worm infestation affecting the patient.
Clinical signs
Clinical features vary; refer to documentation. Patients may have nonspecific gastrointestinal complaints, weight loss, or eosinophilia, but the chart must support a helminth infection.
When to use this code
Use B83.9 when the record confirms helminthiasis but does not name the organism. It is appropriate when notes state worm infection, intestinal helminthiasis, or parasitic infestation without further detail. Check documentation if the species is later identified.
Do not use for
Do not use B83.9 for protozoal infections, fungal disease, or a documented specific helminth that has its own code. Do not assign it when the diagnosis is only suspected.
Coding tip
Query for the exact parasite whenever possible, because a more specific code is preferred over an unspecified one.