Cost-effective screening for urinary tract infections in urogynaecological patients.

This study aims to test the cost-effectiveness of reagent-strip urine nitrite compared with microbiological laboratory testing for screening of urinary tract infections (UTI). The study is a retrospective review of 708 female patients who underwent cystometry during a 1-year period. Urine dipstick nitrite was used as a screening test for UTI while urine cultures were taken as an outcome. Symptoms of UTI were noted. Of 708 patients screened, 70 (9.9%) had a significant UTI. Only 32 (4.5%)of 708 patients were nitrite positive. Urine dipstick nitrite has sensitivity of 40%, specificity of 99%, positive predictive value (PPV) of 88 % and negative predictive value (NPV) of 94%. If the screening test included symptoms for UTI together with urine nitrite, the results are: sensitivity 89%, specificity 31%, PPV 12% and NPV 96%. A combination of screening with urine nitrite and UTI symptoms can increase sensitivity to 89%. A total of 29% of specimens (screen negative=nitrite negative/asymptomatic) can then be excluded from UFEME/culture testing, thus resulting in cost savings.