Evaluation of the role of ultrasonography versus immunologic tests in diagnosis of chronic hepatosplenic sechistosomiasis

ABSTRACT

This study aims to evaluate the sensitivity of different EL1SA techniques versus ultrasonography as a 'stablished tool in diagnosis of chronic hepatosplenic schisosomiasis and assessment of different degrees of morbidity. Based on clinical, sonographic md laboratory testing 100 patients enrolled in this study were devided into 4 main groups Group I with simple intestinal schistosomiasis, group II with periportal fibrosis with or without organomegaly, group III with hepatosplenomegaly and portal hypertension and group IV with advanced morbidity and end stage liver disease. All patients were subjected to ultrasonographic evaluation and serological assessment using Two techniques of ELISA conventional versus Dot ELISA with two types of antigens crude adult worm and soluble egg antigens assessing both IgG and IgM antibodies. The positivity of different ELISA techniques decreases with the advance of morbidity being 95% in group [compared to 15% in group 4 for conventional ELISA and 75% in group I compared to 10% in group 4 for the Dot ELISA. Ultrasonographic evaluation proved to have the main role with the advance of the degree of morbidity and there is no relation between different stages of the disease and the degree of antibody positivity. Antibody burden was higher in the earlier stages of the disease compared to stages of advanced morbidity. IgM antibodies are more prevalent in the earlier stages of the disease while IgG antibodies are more consistent in different stages of the disease being also higher in the [earliest stages of the disease. Based on the conditions of antigen preparations used conventional ELISA was more Sensitive compared to dot ELISA [88% versus 80%] for the conventional using adult worm and soluble egg antigen in group 1 and [68% versus 60%] for the dot ELISA using the Be types of antigens. Conventional ELISA is more sensitive than Fdot ELISA with the adult worm antigen more sensitive than isoluble egg antigens. With advance of morbidity of the disease the sensitivity of both tests as well as the antibody burden decreases that may be attributed to decrease of the intensity of infection as well as low immune status of the individual and this spotlight on the role of ultrasonography with the advance of morbidity. Targeting treatment and control programmes for earlier stages of the disease is essential to reduce heavy antigenic burden that might be responsible for intense immune reaction and progression of the disease state to advanced irreversible morbidity.