Filariasis due to Brugia malayi

This code identifies lymphatic filariasis caused specifically by the parasitic nematode Brugia malayi. This infection typically manifests as lymphedema, elephantiasis, and hydrocele, resulting from the worms obstructing the lymphatic system.

Assign this code when documentation explicitly states a diagnosis of filariasis confirmed to be due to Brugia malayi. This typically follows laboratory identification of microfilariae or adult worms, or serological testing.

• Differentiate from filariasis due to Wuchereria bancrofti (B74.0) or unspecified filariasis (B74.9).
• Ensure the physician's documentation clearly specifies the causative organism.
• Code any associated manifestations, such as lymphedema (I89.0) or elephantiasis (I89.0), as secondary diagnoses.