Use of ultrasound in a study of schistosomal periportal fibrosis in rural Zimbabwe.

Ultrasound was used to diagnose periportal fibrosis (PPF) in a rural Zimbabwean community where Schistosoma mansoni is endemic. Ultrasound findings were compared with stool microscopy and abdominal palpation in 492 adults (305 females). 47 (9.6%) had definite PPF. The prevalence of PPF increased with age (P < 0.001), while S. mansoni egg counts decreased with age. Even within age groups, egg count did not correlate with PPF. No association was found between lifetime alcohol consumption and the presence of PPF. Splenomegaly and mid-line enlargement of the liver were specific (97% and 94%) but insensitive (21% and 28%) markers for PPF. Spleen size varied with S. mansoni egg count independently of the presence or degree of PPF. Endoscopy of 18 patients with PPF revealed oesophageal varices in two, both of whom had severe PPF.