ICD-10 Code B74.9 – Filariasis, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code B74.9 – Filariasis, unspecified
What it is
B74.9 identifies filariasis when the specific parasite or type is not documented. Use it for a parasitic filarial infection that is confirmed, but not further specified in the record.
Clinical signs
Clinical features vary; refer to documentation. Filariasis may present with swelling, skin changes, or lymphatic involvement, but you should code only what is documented and supported by the provider.
When to use this code
Use B74.9 when the chart states filariasis or filarial infection without naming the organism or form. It also fits when the provider confirms filariasis but documentation is too limited to assign a more specific code.
If later notes identify a specific filarial disease, code the more precise diagnosis instead. Check documentation for site, organism, and any related complications before finalizing the code.
Do not use for
Do not use this code for suspected filariasis, ruled-out infection, or nonfilarial parasitic diseases. If the record names a specific filarial condition, choose that code rather than the unspecified category.
Coding tip
When the diagnosis is vague, query for the parasite type or clinical form before defaulting to B74.9.