Hepatic and splenic evaluation by ultrasonography and elastography of fibrosis and portal hypertension in Schistosomiasis mansoni

Abstract

Schistosomiasis is a neglected tropical disease and an important public health problem, mainly due to its magnitude and transcendence. Although most cases are characterized as a mild infection, due to its morbidity, the untreated disease can cause economic burden and incapacitation. Periportal fibrosis (PPF) is the most common complication of schistosomiasis mansoni chronic infection and a large number of deaths are mainly caused by the rupture of esophageal varices resulting from portal hypertension (non-cirrhotic). Regarding the diagnosis and assessment of PPF and portal hypertension, different methods are applied. Although wedge liver biopsy is considered the gold standard, it is not justified in non-surgical patients, whereas percutaneous liver biopsy, even considered informative, does not have sufficient sensitivity. Thus, imaging techniques such as ultrasonography, computed tomography, magnetic resonance imaging and elastography have been applied, not only to support the diagnosis of schistosomiasis, but also to assess signs of portal hypertension. In the present chapter, an evaluation of the non-invasive imaging methods currently available for the evaluation of PPF and portal hypertension in schistosomiasis was carried out. The objectivity of elastography compared to ultrasonography is emphasized, because even though ultrasound is more frequently performed, it still has the limitation of being operator-dependent. Transient elastography (TE) has been applied more and it has shown good results in differentiating clinical forms and PPF stages, in addition to presenting potential in predicting esophageal varices. On the other hand, point shear wave elastography (pSWE) has shown more promising results in the analysis of spleen stiffness, when compared to liver stiffness. Therefore, there is a need for further studies applying liver and spleen elastography in the evaluation of PPF and portal hypertension in these patients.