Urine reagent strips for diagnosis of schistosomiasis haematobium in women of fertile age

Hematuria, proteinuria and leukocyturia were semiquantitatively assessed by reagent strips in single morning urine of women of fertile age visiting the outpatient department of the Mangochi district hospital, Malawi. This was part of a diagnostic approach to female genital schistosomiasis (FGS). In 51 women ova of Schistosoma haematobium were detected in urine by a filtration technique. In 33 of these women ova were also present in genital tissue as demonstrated by microscopic examination of biopsies. In 209 women no ova were found in the single urine filtered. There were significantly higher scores for hematuria, proteinuria and leukocyturia as well as of the combined reagent strip index (RSI) in egg-excreting than in egg-negative women. The sensitivity of a single hematuria, proteinuria and leukocyturia reading was 98, 84 and 73%, respectively. However, the respective specificity was only 24, 22 and 23%. The best prediction of urinary schistosomiasis was achieved by a +2 score for hematuria, of which the sensitivity was 94% and the specificity was 61%. The high false-positive rates can probably be explained by contamination of urine by vaginal secretion. Moreover, cases of schistosomiasis have probably been overlooked because only a single morning urine sample was examined. The total absence of hematuria, proteinuria and leukocyturia, however, may be used to rule out heavy infections in community surveys. There was no difference in reagent strip scores between women with genital and urinary schistosomiasis as compared with those with urinary tract lesions alone. Thus urine analysis reagent strip readings do not help to discriminate between S. haematobium infected women with and without FGS.