Urine circulating soluble egg antigen in relation to egg counts, hematuria, and urinary tract pathology before and after treatment in children infected with Schistosoma haematobium in Kenya

A cohort of 117 school children infected with Schistosoma haematobium was f ollowed-up after therapy with praziquantel (0, 2, 4, 6, 12, and 18 months) and various infection and morbidity parameters (egg counts, hematuria, solu ble egg antigen [SEA] in urine, and ultrasonography-detectable pathology) w ere quantified. At the onset of the study, 97% of the children were positiv e for S. haematobium with a geometric mean egg count of 45.7 eggs/10 mi of urine. Eighty-one percent of the children were positive for SEA in urine wi th a geometric mean SEA concentration of 218.8 ng/ml of urine. Ninety-two p ercent and 56% of the children were microhematuria positive and macrohematu ria positive, respectively, Two months after treatment, all infection and m orbidity indicators had significantly decreased. Reinfection after treatmen t as determined by detection of eggs in urine was observed by four months p ost-treatment while the other parameters remained low. The clearance of SEA was slower than that of egg counts while pathology resolved at an even slo wer pace. Levels of SEA and egg output showed similar correlations with ult rasound detectable pathology; these correlations were better than the corre lation between hematuria and pathology.