HISTOLOGICAL EVIDENCE FOR ADULTICIDAL EFFECT OF LOW-DOSES OF DIETHYLCARBAMAZINE IN BANCROFTIAN FILARIASIS

The ability of diethylcarbamazine (DEC) to kill adult Wuchereria;a ban crofti worms was evaluated by examining lymphatic nodules formed after treatment with 4 different treatment schedules of 193 males living in the endemic area of Greater Recife, Brazil. Lymphatic nodules appeare d in the spermatic cord or upper extremities in 43 of 138 microfilarae mic individuals, in 3 of 30 amicrofilaraemic patients with filarial di sease manifestations, and in 1 of 25 asymptomatic amicrofilaraemic res idents of the endemic area treated with DEC. Fourteen of these nodules were surgically removed 10-150 d after the start of treatment. Regard less of the DEC dosage and schedule used, all nodules contained damage d and degenerating adult worms. An exuberant granulomatous process wit h large numbers of eosinophils and progressive fibrosis gradually deve loped around the dead parasites. The mechanism(s) by which DEC killed adult W. bancrofti could not be determined.