Neuroschistosomiasis: clinical symptoms and pathogenesis.

Neuroschistosomiasis, referring to schistosomal involvement of the CNS, when symptomatic, is a severe disorder in which prognosis depends largely on early diagnosis and treatment. It is an underdiagnosed disorder, but has been increasingly reported in populations in endemic areas and in tourists. CNS involvement can occur at any time during schistosomal infection. Both the brain and the spinal cord can be affected. Schistosoma mansoni and Schistosoma haematobium usually cause myelopathy, whereas Schistosoma japonicum usually causes encephalic disease. There are substantial differences in the pathogenesis, clinical presentation, and outcome of the neurological disorder, depending on the phase and clinical form of schistosomiasis in which it occurs.