ULTRASONOGRAPHY OF URETERAL ABNORMALITIES INDUCED BG SCHISTOSOMA-HAEMATOBIUM INFECTION BEFORE AND AFTER PRAZIQUANTEL TREATMENT

Objective To describe the ultrasonographic appearance of ureteric lesi ons due to Schistosoma haematobium infection and to report prevalence rates of such lesions in endemic communities in Mall before and after praziquantel treatment. Subjects and methods The total population (n=9 61) of three S. haematobium-endemic villages in Mali was examined ultr asonographically to detect urinary tract morbidity. Urine was tested f or S. haematobium ova and for haematuria. An identical follow-up study was performed 1 year after mass treatment with praziquantel. Results Prevalence rates of S. haematobium infection in the three villages wer e 53%, 72% and 73%. Ultrasonography revealed dilatation of the ureters in 143 subjects (15%). In 20 of these, mainly children and adolescent s, thickening and irregularities of the ureteric wall with distal uret er obstruction were directly visualized on ultrasonography. Within the bladder of two others, an intraluminal structure of ureterocele-like appearance was seen. None of these alterations has been previously des cribed as an ultrasonographic feature of schistosomal uropathy. Active S. haematobium infection and microhaematuria were found in 21 and 20 of these 22 subjects respectively, Significant renal obstruction was p resent in 10 of them. One year after treatment, an entirely normal uri nary tract was found in 85% of 104 re-examined individuals who had had ureter dilatation. Ureteric wall thickening or ureterocele-like lesio ns had disappeared in 95% of subjects. Conclusions The role of ultraso und in the evaluation of schistosomal uropathy is confirmed. Ureteric wall abnormalities causing strictures and ureterocele-like lesions of the ostium must be regarded as further ultrasonographic features of th is condition. The study documents the excellent reversibility of urete ric abnormalities after antischistosomal treatment in children and ado lescents, thus emphasizing the need for early and efficient medical tr eatment of the infection.