Intermittent chemotherapy with trichlorfon (metrifonate) reverses proteinuria, hematuria, and leukocyturia in urinary schistosomiasis: results of a three-year field study.

Trichlorfon (metrifonate) was given intermittently to 37 schoolboys with urinary schistosomiasis living in a hyperendemic area of the Sudan. Patients were followed up for three years. Initially, 10 mg of trichlorfon/kg of body weight was administered; this dosage was repeated 14 days and 16 months later. Patients still excreting eggs after 24 months received a fourth dose. At month 24, 61% and at month 36, 56% of the patients had no detectable egg excretion; the others showed severe reduction of egg output. The number of ova excreted was always paralleled by a combined scale of hematuria, leukocyturia , and proteinuria, as assessed by urine analysis reagent strips. Quantitative urine analysis at month 36 revealed pathological findings in only eight individuals. Thus, trichlorfon given three or four times in a dose of 10 mg/kg of body weight spaced over a period of two years was highly effective in reducing parasite load and disease in children living under hyperendemic conditions.