Efficacy of administration of praziquantel on 2 days 2 weeks apart against Schistosoma japonicum eggs in mice.
We compared a group of mice given multiple oral doses of praziquantel (PZQ) on 1 day 7 weeks after infection with Schistosoma japonicum and another group given multiple doses of PZQ over 2 days (7 and 9 weeks after infection) by examining the number of schistosome eggs and oograms in their tissues and feces. In the 1-day-protocol group (4 x 100 mg/kg x 1 day), calcified dead eggs or shells accounted for 77.4 and 70.1% of the total EPG (the total number of immature eggs, mature eggs, and calcified eggs and shells per 1 g tissue) in the liver and small intestine, respectively, 11 weeks after infection. Shells accounted for nearly half of the total EPG (54.3% liver and 46.6% small intestine). Mature eggs accounted for 8.4% (liver) and 5.1% (small intestine) of the total EPG. Only shells were found in the feces. In the 2-day-protocol group (4 x 100 mg/kg x 2 days, 2 weeks apart), dead eggs accounted for 87.2 and 89.5% of the total EPG in the liver and small intestine, respectively, 11 weeks after infection. Shells accounted for 62.5% (liver) and 75.8% (small intestine) of the total EPG. In the 2-day group, mature eggs accounted for 0.9% (liver) and 0.6% (small intestine) of the total EPG. In liver and small intestine, the EPG of immature and mature eggs in the 2-day group was significantly smaller than in the 1-day group. Especially, the tendency was clear in the case of the EPG of mature eggs. There were no schistosome eggs in the feces of the 2-day group. We found that administration of PZQ over 2 days separated by a 2-week interval was effective against S. japonicum.
Hirose
Yoshinori
Y
Department of Tropical Medicine and Parasitology, Dokkyo University School of Medicine, Mibu, Tochigi 321-0293, Japan.
Kirinoki
Masashi
M
Matsuda
Hajime
H
D000818:Animals; D000871:Anthelmintics / Q000008:administration & dosage* / Q000627:therapeutic use; D004334:Drug Administration Schedule; D005243:Feces / Q000469:parasitology; D005260:Female; D007421:Intestine, Small / Q000469:parasitology; D008099:Liver / Q000469:parasitology; D051379:Mice; D008813:Mice, Inbred ICR; D010270:Parasite Egg Count; D011223:Praziquantel / Q000008:administration & dosage* / Q000627:therapeutic use; D012549:Schistosoma japonicum / Q000187:drug effects* / Q000196:embryology; D012554:Schistosomiasis japonica / Q000188:drug therapy* / Q000469:parasitology; D013997:Time Factors; D016896:Treatment Outcome
D000871:Anthelmintics; D011223:Praziquantel