Schistosoma japonicum infection: clinical significance of ultrasound findings.

Schistosoma japonicum infection can cause severe hepatic complications associated with portal hypertension, which may lead to death by bleeding from esophageal varices. Ultrasonography (US) enables the identification of two different types of liver fibrosis characteristic for S. japonicum infection: interseptal fibrosis (ISF) and portal fibrosis (PF). To date, these two forms of liver fibrosis have not been sufficiently investigated with regard to their potential to cause portal hypertension. Among the 121 reports published, only 56 (46.3%) distinguish between ISF and PF. In 31/56 (55.4%) of these publications, patients with only ISF, two (3.6%) with only PF, as well as 23 (41.1%) with concomitant ISF and PF, are reported. US signs of portal hypertension are reported in 10/25 (40.0%) of publications reporting PF, of which 2/2 (100%) of publications report PF alone and 8/23 (34.8%) of publications report concurrent PF and ISF. Also, 2/31 (6.5%) of publications report that ISF alone is associated with portal hypertension. Thus, PF appears to be the main risk factor for portal hypertension. Future studies need to assess the exact nature of liver fibrosis caused by S. japonicum in a standardized way to clarify the individual contributions of PF and ISF to morbidity.