Abnormalities of the leg lymphatics are not specific for bancroftian filariasis

Studies using conventional angiography or non-invasive scintigraphy have re vealed widespread abnormalities in the lymphatics of the legs of patients w ith bancroftian filariasis, regardless of whether clinical lymphoedema is p resent. To determine if the observed changes were specific for filarial inf ections, we imaged the lymphatics of both legs in native residents of an ar ea in Brazil where filariasis is not endemic. Study participants mere match ed by age, socioeconomic status and physical activities to patients with fi lariasis in Recife, evaluated in parallel. Based on textbook criteria, only one of 15 study participants had a completely normal lymphoscintigram. Mod est to seven pathology of the leg lymphatics was observed in the remaining 14 residents of the non-endemic area and in 49 of 50 patients with bancroft ian filariasis. These results indicated that factors other than filarial wo rms an a common cause of subclinical pathology of the leg lymphatics in nor th-eastern Brazil, and that the latter is not specific for bancroftian fila riasis.