OBJECTIVE: To evaluate sonographic features associated with morbidity in patients with chronic clinical presentations of schistosomiasis mansoni, according to the protocol proposed by the World Health Organization (WHO). Materials and Methods: Two distinctive populations were evaluated: a) patients from an endemic area, and b) patients from a tertiary institution, with histopathologically confirmed periportal fibrosis. INCLUSION CRITERIA: diagnosis confirmed by parasitological stool examination for Schistosoma mansoni (Kato-Katz method). EXCLUSION CRITERIA: positive serology for HIV, HTLV-1, HBV or HCV. The Niamey protocol on ultrasonography proposed by the WHO was utilized. RESULTS:As the measures of periportal spaces were isolatedly evaluated, no alteration was observed in 21% of the tertiary institution patients with advanced disease. As all parameters of the Niamey protocol were considered, 100% of patients from the tertiary institution, with severe disease, presented advanced periportal fibrosis. In hepatosplenic patients from endemic areas, fibrosis was not identified at ultrasonography. CONCLUSION: The sonographic protocol proposed by the WHO can detect advanced periportal fibrosis in patients with severe form of disease with higher sensitivity than the isolated measurement of periportal space. The complexity involved in the sonographic identification of early stages of periportal fibrosis in endemic areas may give rise to the field of diagnostic supplementation and to a continued improvement of sonographic protocols in these areas.

Keywords: Schistosomiasis mansoni; Morbidity; Periportal fibrosis; Ultrasonography.