Schistosoma haematobium infection with egg deposition in the tissue gives rise to inflammation and granuloma formation leading to subsequent urinary tract pathology. Eosinophils, present in granulomas, participate in the inflammatory response around deposited eggs. Presence of eosinophils in urine might be a good indicator of bladder inflammation and hence urinary tract pathology. ultrasonography is an established, simple method of detecting urinary tract pathology in the field but this method can not visualize early inflammatory reactions in the bladder wall. Differential urine leucocyte or total eosinophil counts are time consuming and difficult to perform under field conditions and not realistic in the context of a control program. Eosinophil cationic protein (ECP) in urine gives an estimate of the degree of eosinophiluria and recently a sensitive ELISA assay for ECP has been developed. Schistosome eggs have been found viable up to several months after treatment. Excreted S. haematobium egg antigen in urine will indicate presence of viable eggs in the bladder wall.
The objectives of the proposed project are:
- to evaluate and further develop the ECP assay including development of an ECP reagent strip and to apply the assay in the study of factors responsible for eosinophil activation and degranulation.
- to evaluate the assay for S. haematobium egg antigen in urine with emphasis on antigens released in urine from bladder tissue
- to assess the effect of treatment and reinfection on urinary tract pathology among school children in Kenya and Tanzania using the non-invasive assays for ECP and egg antigen in urine compared to ultrasonography findings and conventional diagnostic methods
- to train Kenyan and Tanzanian investigators in laboratory techniques for Ecp and S. haematobium egg antigen in urine and on ultrasonograph including assessment of intra- and interobserver variations. The ECP and S. haematobium egg antigen assays will provide new non invasive tools for evaluation of chemotherapy effect and morbidity assessment in urinary schistosomiasis helping to understand the dynamic process of post treatment resolution and reappearance of urinary tract pathology.
Funding SchemeCSC - Cost-sharing contracts
2100 København Ø
2300 RC Leiden