Microfilaria Screen

Diagnostic Use

Microfilaria screening is used to detect the larval stage of filarial worms in peripheral blood in filarial infections such as lymphatic filariasis and loiasis. Processed from the FBC sample, patients with microfilaria may have an associated eosinophilia.
Microfilaria is often found in patients from tropical areas, especially the Pacific Islands where the parasite is endemic. It causes blockage of the lymphatic system. W bancrofti (var. Pacifica) is most commonly seen here in New Zealand.
Certain microfilaria have a nocturnal periodicity, and therefore blood collection is best performed at night. W. bancrofti (var. Pacifica) does not show nocturnal periodicity.
A specimen concentration procedure may be performed to increase the chances of detecting the parasite.