A comparative study of available diagnostic tools for lymphatic filariasis - abstract

ABSTRACT

Venous blood from 300 patients attending a filaria clinic in Georgetown, Guyana, was taken and assayed by ELISA for IgG and IgM antibodies against filaria parasites, and by microscopic methods before and after concentration procedures for microfilaraemia. Negative serum titres (<132) of IgG and IgM coincided with 90 per cent and 65 per cent, respectively, of positive microscopy. A membrane filtration system (95 per cent) was slightly better than a centrifugation (92.5 per cent) technique, but significantly more efficient than a thick smear preparation (75 per cent) for the detection of microfilaraemia. The filtration system was vastly superior for yields of microfilaria. However, the Knott's concentration (sedimentation) was the most economical in terms of technician time and materials. Most microscopically confirmed filaria cases were in the 20 - 29 year-age group (25 per cent), followed by the broad 30 - 69 year-age group (10 - 12 per cent). Males were more commonly affected by the ratio of 2.6 1. Symptoms included swollen limbs, tenderness, fever, swollen glands, headache and joint pains but 17 (42.5 per cent) patients were asymptomatic (AU)