Les bilharzioses : aspects épidémio-cliniques et diagnostiques

Schistosoma is a fluke of the trematode family and has separate male and female forms. A freshwater snail is the intermediate host. The adult fluke are found in the venous system. The diagnosis should be considered in subjects living in, or returning from, endemic areas who have urinary symptoms, often including haematuria, and a peripheral blood eosinophilia. Confirmation of the diagnosis relies on the identification of the characteristic eggs, either in the urine and the stools or on bladder or rectal biopsy. They can also be found in biopsy specimens from the vagina, cervix and lever. The egg's terminal or lateral spine is not always visible on histological sections. Ziehl's staining method can be used to differenciate the different species. Serology is useful for diagnosis in the absence of egg detection in clinical sample. Antibody levels can be monitored serially to assess clinical cure after treatment. Radiological techniques can help to graduate the degree of severity of organ damage (ureters, bladder). Praziquantel with or without surgical intervention is the treatment of choice. Follow-up, which should include, Full Blood Count (FBC) (Angleterre, Irlande) or Complete Blood Count (CBC) (USA), serology and examination of the urine and stools for parasites should not be completed for at least six to eight weeks, as it takes this length of time for the eggs to migrate through the tissues in which they are embedded.