Comparative randomised trial of high and conventional doses of praziquantel in the treatment of schistosomiasis mansoni

The efficacy of oral praziquantel in the treatment of schistosomiasis has been considered low by most public health institutions. In this paper, we compared the efficacy of two dosages of praziquantel (80 mg/kg vs. 50 mg/kg) in patients with chronic schistosomiasis mansoni. Two hundred eighty-eight patients with schistosomiasis from a community in Brazil were randomly divided into two groups: 145 patients (Group 1) received 80 mg/kg body weight of oral praziquantel divided in two equal doses with 1 h interval and 143 patients (Group 2) received 50 mg/kg body weight of oral praziquantel. To keep the study masked, patients in Group 2 received placebo 1 h after the first dose. All patients were subjected to clinical and ultrasonographic examination. Cure assessment was performed by repeating two stool examinations, by a quantitative method, at 30, 90 and 180 days after treatment. The morbidity of schistosomiasis was low, with a few cases of light periportal thickening and 16 cases of mild splenomegaly. The cure rates were 89.7 percent for Group 1 and 83.9 percent for Group 2. There was no difference in the efficacy of both therapeutic dosages of praziquantel assayed. The adverse reactions were more frequent with higher dosage.

Assessment of antibilharzial and biochemical effects of triclabendazol in experimental schistomiasis

Schistomiasis is one of the major public health problems, and for more than two decades Praziquntel [PZQ] has remained the drug of choice for its treatment. However, studies proved that reliance on one drug raised the concern of development of tolerance or even resistance. The present work aimed at studying the effect of different schedules of the flukicidal drug triclabendazol [TCBZ], in a dose of 120mg/kg body weight, on Schistoma mansoni worm load, female fecundity and egg deposition in liver and intestine of infected mice, and at studying its biochemical toxic effects on some liver enzymes activities. The present findings indicated that the administration of TCBZ to mice infected with Egyptian S. mansoni strain was not effective except when the drug was given after the start of egg shedding in the stools. However, the anti-schistosomal effect was moderate as the results showed 50% reduction in worm burden and around 40% reduction in liver and intestinal egg loads. On the other hand, the impact on oogram pattern was not clear except regarding the percentage of dead ova which was much higher than the corresponding control. As regards the biochemical parameters studied, no change in the activity of all tested enzymes was observed. However, animals which received two doses of the drug after the start of egg shedding exhibited 24% reduction in alanine transaminase [ALT] activity. Our results indicated that, still, there is no alternative to prazquantel and there is an urgent need for discovery of new antischistosomal drugs. In addition studying different combinations and schedules of the already available drugs as artemether and TCBZ is recommended

Studies on the correlation between antischistosomal antibodies and infertility in men

Schistosomiasis affects the genitourinary system and thus might affect fertility. The present study tried to assess the relation between antischistosomal antibodies in serum and fertility. 44 oligospermic men [mean spermatic count 11.21 million sperms/ml] and 20 fertile men were studied. Both groups were treated from schistosomiasis years before and had no evidence of hepatosplenomegaly. Indirect hemagglutination test was positive in 81.8% of infertile men and 50% [P >0.05] of fertile men, while the circumoval precipitin test was positive in 18% of infertile men and 10% of fertile men [P >0.05]. This showed that there was no correlation between the level of antischistosomal antibodies in serum and fertility. It could be suggested that uncomplicated schistosomiasis is unlikely to be related to male infertility in Egyptians