Microfilaria - QBC Method

Function

The Microfilaria test using the Quantitative Buffy Coat (QBC) method is a diagnostic technique used to detect the presence of larval stages (microfilariae) of filarial parasites in the blood. These parasites, such as Wuchereria bancrofti and Brugia malayi, are responsible for lymphatic filariasis. The QBC method utilizes a specialized capillary tube coated with acridine orange (a fluorescent stain) and a high-speed centrifuge to concentrate the parasites in the buffy coat layer, making them easier to visualize under a microscope.

Why it is Ordered

This test is ordered for patients living in or traveling from tropical or subtropical regions who present with:

• Lymphedema: Swelling of the limbs or genitals (Elephantiasis).
• Hydrocele: Accumulation of fluid in the scrotum.
• Tropical Pulmonary Eosinophilia: Characterized by coughing and wheezing.
• Fever and Lymphadenitis: Recurrent episodes of inflamed lymph nodes.

Associated Conditions

• Lymphatic Filariasis: The primary disease caused by these parasites, leading to significant disability and social stigma.
• Loiasis: Caused by Loa loa, often associated with eye worms or localized swellings.
• Onchocerciasis (River Blindness): Though microfilariae are usually found in skin snips, some species may appear in blood.
• Bancroftian Filariasis: Specific to the Wuchereria species.