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. 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