Test Directory

The filaria IgG4 assay may be helpful in the diagnosis of infections with major filaria parasites, including Wuchereria brancrofti, Brugia malayi, Onchocerca volvulus, and Dirofilaria immitis. Because cross-reactivity may occur in infections with other nematodes, identification of parasites in blood or other body fluid remains the definitive means of diagnosis. A negative result on this test does not rule out chronic filarial infection.

Specimen Type: Serum

Collection Container: Red Top, Plain

Desired Specimen Volume: 0.2 mL

1. Collect a red top, plain tube via venipuncture

1. Separate serum from cells.
2. Transfer 0.2 mL of serum to a clear aliquot tube (screw cap).

Transport to the laboratory at room temperature.

See patient report.

This assay detects Filaria IgG4 associated with index infections caused by the major filarial parasites, including Dirofilaria immitis, Wuchereria brancrofti, Brugia malayi, and Onchocerca volvulus. Chronic filarial infections manifesting as elephantiasis may not show a significant IgG4 response and cannot be index ruled out using this test. Samples containing antibodies to other nematodes, particularly Strongyloides, may cross-react in the assay.

• Filariasis