Study on histopathology, ultrasonography and some special serum enzymes and collagens for 38 advanced patients of schistosomiasis japonica

Abstract

Thirty-eight cases clinically diagnosed as advanced schistosomiaisis were subject to splenectomy in Dongzhi County Special Hospital for Schistosomiasis because of portal hypertension, splenomegaly and/or hypersplenism. Liver biopsy was undertaken in all cases during surgical intervention. Before operation, ultrasonography on the liver and spleen was carried out. Also done was biochemical assay on several indices related to liver damage and fibrosis. Among the 38 cases, 24 were diagnosed as schistosomiasis by the finding of eggs in feces, 13 were diagnosed by positive serological test with IHA or COPT, and only in one case, the diagnosis of schistosomiasis was doubtful before operation. However, the eggs were found in the liver section upon histological examination. All the 38 cases had symptoms and signs of portal hypertension and most of them had general symptoms. Histories of hematemesis and melena were recorded in three cases. The causes of hospitalization were mainly splenomegaly and abdominal distension, and two were suffering from upper gastrointestinal bleeding. Upon histopathological examination, schistosome eggs were found in 33 out of 38 cases. Advanced schistosomaiasis was shown in 18 cases and schistosomiasis associated with hepatitis or cirrhosis was seen in other 20 patients. The main pathological changes were egg granulomas with different degrees of fibrosis and some differences in the pathological changes between schistosomal liver fibrosis (SLF) and mixed liver cirrhosis (both schistosome and hepatitis in origin) were seen. Compared with normal ultrasonography, in all the 38 cases, the length of the left and right liver, and the spleen, and the thickness of the left liver, the width of portal trunk, were all out of normal ranges. The differences between the patients and normal records were significant. However, there were no statistically significant differences in terms of above-mentioned indices as well as liver parenchyma changes on ultrasound between advanced schistosomaiasis and schistosomiasis complicated with hepatitis or cirrhosis (all P>0.5). According to WHO classification criteria on ultrasonography for schistosomiasis, among 20 cases combined with hepatitis or cirrhosis, 11 cases fell in Grade II, and nine cases in Grade III hepatic fibrosis, whereas among 18 cases with schistosomiasis fibrosis, 12 and six were in Grade II and III, respectively. The mean value of serum MAO, PIIIP, IVC and HA in the 38 cases were all significantly higher than normal range. However, no significant differences (all P>0.1) were seen between advanced schistosomiasis and those complicated with hepatitis or cirrhosis in terms of the levels of the four indices. The results showed that ultrasonography has its importance in the diagnosis and evaluation of liver fibrosis. However, in differentiation of the two types of liver damage, ultrasound does not provide important information. Histopathological examination, on the other hand, can provide useful information to identify the hepatic diseases.

Introduction

The majority of advanced patients of schistosomiasis japonica have been in a sub-clinical state but some indices indicating the disease status are not sensitive, especially for the transition from chronic to advanced stage of the disease. The clinical manifestations and indices indicating the transition are non-specific, for instance, hemorrhage and hypoproteinemia etc, by which liver fibrosis due to schistosomiasis cannot be confirmed definitely. Histologically, main pathologic alterations of schistosomiasis are granuloma formation around schistosomal eggs which deposit in the parenchyma with continuously inflammatory fibrosis, especially in the liver. It has been the project for study of schistitosomiasis as how to use physical and biochemical examination results to indicate the transition from chronic to advanced stage of the disease and the degree of lesion, especially the degree of intrahepatic fibrosis.

Now ultrasonographic examination is a practical, non-invasive and harmless technique for testing directly the degree of lesion of hepatic parenchyma and has been extensively used as a tool in studies of epidemiology and pathology of schistosomiasis. It is not only used for clinical diagnosis in hospitalized patients, but also for screening cases of schistosomiasis in communities. Many studies on ultrasonographic examination for schistosomiasis, especially for liver fibrosis, have been reported (Cautinho, 1990, Mott et al., 1992, Abdel-Wahab and Strickland, 1993, Yuan et al., 1993, Strickland and Abdel-Wahab, 1993, Bisier et al., 1995).

Publications on histopathological examination for schistosomiasis japonica, either by autopsy or via liver biopsy, are very few in the literature, especially during the recent years owing to the facts that death due to schistosomiasis has been rare after praziquentel chemotherapy became available since late 1970s, and liver biopsy is an invasive technique and sometimes harmful to patients (Chen and Mott, 1989). During 1997–1998, splenectomy was performed in the Special Hospital for Schistosomiasis in Dongzhi County, Anhui Province, China in 38 cases clinically diagnosed as advanced schistosomiasis for the surgical treatment of their splenomegaly and/or hypersplenism. Before splenectomy, ultrasonographic and biochemical examinations were carried out to compare those with histopathological data from liver biopsy during splenectomy. This study is to compare results of ultrasound examination (mainly on the liver and spleen) and some special serum enzymes and collagens tested with the results of histopathological studies on the liver and spleen in 38 advanced patients diagnosed clinically, and to analyze with emphasis on the correlation between hepatic lesions and results of ultrasonographic and serological indices so as to use ultrasonography alone or in combination with serum examination to indicate the presence of hepatic lesion and its degree, used as a background for clinical diagnosis, treatment and prognosis.