Eficácia do praziquantel no tratamento da esquistossomose mansônica: comparação das dosagens por via oral de 50 mg/kg versus 80 mg/kg de peso corporal

Abstract

The efficacy of oral praziquantel in the treatment of schistosomiais - around 70% - has been considered low by most public health institutions in different countries. To evaluate the efficacy of higher doses of praziquantel in the treatment of chronic schistosomiasis mansoni a randomized, triple masked study, using praziquantel in two different doses was set up. 288 patients with eggs of S. mansoni in the stools, from a community in Governador Valadares (MG), with a prevalence for schistosomiasis of 22.5%, were randomized in two distinct groups; i) 145 (Group 1) received 80 mg/kg, body weight of oral praziquantel divided in two equal doses given with one hour interval; ii) 143 (Group 2) received 50 mg/kg, body weight of oral praziquantel - and to keep the study masked, they were given a dose of placebo one hour later. Before treatment all patients were subjected to clinical and ultrasonographic examination. The cure assessment was performed by repeating two stool examinations at 30, 90 and 180 days after treatment. The cure rates were of 89,7% for group 1 and 83,9% for group 2. As the study groups were comparable, adjustments were not needed before statistical analysis. The adverse events were as frequent and of the same sort of those already described in the literature; nevertheless, they were more frequent in Group 1 patients, when the adverse events were investigated 48 hours after treatment. The morbidity of schistosomiasis, evaluated by clinical and ultrasonographic examination, was low with a few cases of light periportal fibrosis and splenomegaly. In summary, there was no difference in the efficacy of both therapeutic doses of praziquantel assayed herein. It was observed higher frequency of adverse effects in the group treated with higher dose (80 mg/kg/body weight).