Eighteen children with schistosomiasis mansoni were treated with oxamniquine (20mg/kg body weight, single oral dose) and follow-up was continued for twenty two months post-treatment, with twenty two stool examinations and one rectal biopsy in the last month. From 16 children considered as cured, the results of the oogram in the rectal snips revealed in 5 (31.3%), no eggs; in 11 (68.7%), calcified eggs; in 8 (50%), "recent-dead" eggs and in 3 (18.8%), granulomas. To study the dynamics of disappearance of S. mansoni eggs in the tissues, 31 white mices were infected with 100 S. mansoni cercariae and after 45 days treated with an association of known schistosomicidal drugs. The animals were sacrificed 30, 90, 180, 260 and 400 days after treatment and ileal fragments were microscopically examined and oograms were performed. A significant decrease in the number of dead eggs was observed, and after one year post-treatment only semi transparents, shells and calcified eggs as well as granulomas were still found. The finding of those types of eggs alone is a strong evidence of parasitological cure.
Schistosomiasis mansoni; Dead eggs; Cure control; Treatment; Rectal biopsy