Development of an experimental model of schistosomal myeloradiculopathy.

Schistosomal myeloradiculopathy (SMR) is a severe form of presentation of schistosomiasis in which Schistosoma spp. affect the spinal cord. The aims of the present study were to develop an animal model of SMR caused by S. mansoni, to characterize both sensory and motor abnormalities in the infected animals, and to investigate the relationship of the sensory, motor and histological findings with the progression of the infection over time. Mechanical sensitivity and behavioral tests were performed followed by euthanasia in male Wistar rats divided into six groups of five animals each, on days 5, 10, 20 and 30 after infection of S. mansoni eggs. The controls were subjected to the same procedure but were administered phosphate-buffered saline (PBS). The spinal cord was removed and subjected to histological analysis. S. mansoni eggs were found in the spinal cord of 25% of the infected animals, which belonged to the groups that exhibited more significant reduction of the superficial mechanical sensitivity, thermal sensitivity and muscle strength. This model proved to be satisfactory to assess functional changes in Wistar rats and might be used in studies investigating the pathogenesis of SMR. To our knowledge, this is the first experimental model of SMR.