Pierluigi Marzuillo1, Stefano Guarino2, Daniela Furlan2, Anna Pecoraro2, Marcella Pedullà2, Emanuele Miraglia Del Giudice2, Angela La Manna2. 1. Department of Woman, Child and of General and Specialized Surgery, Università degli Studi della Campania "Luigi Vanvitelli", Via Luigi De Crecchio 2, 80138, Napoli, Italy. pierluigi.marzuillo@gmail.com. 2. Department of Woman, Child and of General and Specialized Surgery, Università degli Studi della Campania "Luigi Vanvitelli", Via Luigi De Crecchio 2, 80138, Napoli, Italy.
Abstract
We evaluated, both in toilet-trained and not-toilet-trained children, the impact of cleaning the genital area with plain water on the false positive rate at urine dipstick, and evaluated which factors could be associated to falsely positive findings. We prospectively enrolled 612 patients consecutively attending our nephro-urological outpatient clinic. Firstly, we performed urine dipsticks on urine samples collected from patients whose genital area had not been cleaned before. Then we collected a second sample from the patients with positive urine dipstick, after their genital area had been cleaned with plain water. The urine dipstick was considered falsely positive if we documented its normalization at urine dipstick made on the urine sample collected after cleaning the genital area. We found a falsely positive urine dipstick in 25.5% of the patients, and more in detail in 22.9% of the not-toilet-trained children, and in 26.6% of the toilet-trained children (p = 0.37). The only factors leading to a significant increased RR to have a false positive were non-retractable foreskin (RR = 4.38; 95% CI, 2.15-8.9; p = 0.0001) and female gender (RR = 2.47; 95% CI, 1.77-3.44; p < 0.0001). CONCLUSION: Cleaning the genital area with plain water should always be performed before collecting urine samples, even if only a urine dipstick without culture is needed. What is Known: • Cleaning the genital area reduces the urine bacterial contamination rate in populations of toilet-trained pediatric patients. • There are no studies assessing the impact of cleaning the genital area on the quality of the urine dipstick, nor on which factors could affect the urine dipstick findings. What is New: • Falsely positive urine dipstick was found in 25.5% of the 612 prospectively enrolled toilet-trained and not-toilet-trained children. • Non-retractable foreskin and female gender significantly increases the relative risk of falsely positive urine dipsticks.
We evaluated, both in toilet-trained and not-toilet-trained children, the impact of cleaning the genital area with plain water on the false positive rate at urine dipstick, and evaluated which factors could be associated to falsely positive findings. We prospectively enrolled 612 patients consecutively attending our nephro-urological outpatient clinic. Firstly, we performed urine dipsticks on urine samples collected from patients whose genital area had not been cleaned before. Then we collected a second sample from the patients with positive urine dipstick, after their genital area had been cleaned with plain water. The urine dipstick was considered falsely positive if we documented its normalization at urine dipstick made on the urine sample collected after cleaning the genital area. We found a falsely positive urine dipstick in 25.5% of the patients, and more in detail in 22.9% of the not-toilet-trained children, and in 26.6% of the toilet-trained children (p = 0.37). The only factors leading to a significant increased RR to have a false positive were non-retractable foreskin (RR = 4.38; 95% CI, 2.15-8.9; p = 0.0001) and female gender (RR = 2.47; 95% CI, 1.77-3.44; p < 0.0001). CONCLUSION: Cleaning the genital area with plain water should always be performed before collecting urine samples, even if only a urine dipstick without culture is needed. What is Known: • Cleaning the genital area reduces the urine bacterial contamination rate in populations of toilet-trained pediatric patients. • There are no studies assessing the impact of cleaning the genital area on the quality of the urine dipstick, nor on which factors could affect the urine dipstick findings. What is New: • Falsely positive urine dipstick was found in 25.5% of the 612 prospectively enrolled toilet-trained and not-toilet-trained children. • Non-retractable foreskin and female gender significantly increases the relative risk of falsely positive urine dipsticks.
Authors: Gabrielle J Williams; Petra Macaskill; Siew F Chan; Robin M Turner; Elisabeth Hodson; Jonathan C Craig Journal: Lancet Infect Dis Date: 2010-04 Impact factor: 25.071
Authors: Pierluigi Marzuillo; Stefano Guarino; Anna Grandone; Allegra Di Somma; Nicoletta Della Vecchia; Tiziana Esposito; Giulia Macchini; Rosaria Marotta; Andrea Apicella; Mario Diplomatico; Pier Francesco Rambaldi; Laura Perrone; Emanuele Miraglia Del Giudice; Angela La Manna; Cesare Polito Journal: J Urol Date: 2017-05-26 Impact factor: 7.450