[Detection of specific IgG in the sera of patients with chronic schistosomiasis japonica by dot-ELISA with the recombinant Sj26-Sj32 fusion protein].

OBJECTIVE: To study the diagnostic value of the Dot ELISA with rSj26-Sj32 fusion protein for chronic schistosomiasis japonica. METHODS: rSj26-Sj32 fusion protein and SjAWA were used to establish the HRP-IgG-Dot-ELISA. Serum samples from patients with chronic schistosomiasis japonica (40 cases), clonorchiasis sinensis (21 cases), paragonimiasis westermani(13 cases), alveolar echinococcosis (10 cases), cystic echinococcosis(9 cases), hepatitis B(20 cases), pulmonary tuberculosis (20 cases) and healthy persons (43 cases) were examined. RESULTS: Sensitivity and specificity were respectively 92.5% (37/40) and 95.4% (41/43) for rSj26-Sj32-Dot-ELISA and 95.0% (38/40) and 93.0% (40/43) for SjAWA-Dot-ELISA, and there was no significant difference between two antigens (P > 0.05). There were different cross reactions to the sera of patients with clonorchiasis sinensis, paragonimiasis westermani or alveolar echinococcosis, but no cross reaction to the sera of patients with cystic echinococcosis, hepatitis B or pulmonary tuberculosis. The positive and negative predictive value and efficiency of diagnosis of rSj26-Sj32-Dot-ELISA for chronic schistosomiasis japonica were 84.1% (37/44), 97.7% (129/132), and 94.3% (166/176), respectively, and those of SjAWA-Dot-ELISA were 77.6% (38/49), 98.4% (125/127), and 92.6% (163/176), respectively. There was no significant difference between the two methods (P > 0.05). CONCLUSION: rSi26-Si32 fusion protein can be applied to immunodiagnosis for chronic schistosomiasis japonica.