TITLE:
Evaluation of the Effectiveness of Urine Dipstick in the Screening of Urinary Infection in Relation to the Reference Method: The Cytobacteriological Examination of Urine
AUTHORS:
Bianza Moise Bakadia, Bakamona Lina Babidi, Tshilumbayi Falone Mutoba, Mazono Pierre Mbang, Kabengele Arlette Ndaya, Mutumukole Jeanluc Biampata, Ilunga Eric Kasamba
KEYWORDS:
Urine Dipstick, Urinary Tract Infection, Cytobacteriological Examination
JOURNAL NAME:
Open Access Library Journal,
Vol.5 No.8,
August
16,
2018
ABSTRACT: The cytobacteriological examination of urine is a biological test most commonly asked in the hospital. The results of a large part of urinary sample analyzed are negative, representing a heavy workload for bacteriology laboratories, burden that we would like to limit. In this context the aim of our study was to evaluate a screening test for urinary tract infection by urine dipstick compared to the reference method; the cytobacteriological examination of urine finally promotes the realization of the urine dipstick before any urine culture. We selected 600 patients whom the physician asked the cytobacteriological examination of urine, and on every patient, we proceeded to urine collection and finally realized the urine dipstick before urine culture; two parameters on urine dipstick have helped us to confirm the negativity and positivity of the dipstick, its leukocytes and nitrites. The results of urine dipstick are positive if one or less of the two tests, leukocyte and nitrite is positive; the result is negative if both tests are negative. The urine culture was done on cled agar and bacterial identification was made on cultural characteristics, biochemical (API 2OE gallery of biomerieux). The results of urine culture were collected 72 hours after culture. For the analysis of results, the sensitivity, specificity, predictive values (positive predictive value and negative predictive value), the youden index, the proportion of correctly-classified subjects and the likelihood ratio (positive likelihood ratio and negative likelihood ratio) were calculated. The urine dipstick has the sensitivity of 96%, specificity of 90%, the positive predictive value of 74%, the negative predictive value of 98.8%, youden index of 0.86, the proportion of subjects correctly classified of 91.6%, a positive likelihood ratio of 9.6 and a negative likelihood ratio of 0.04. In the light of these results, the urine dipstick is an elimination test, by its very high sensitivity (96%), its high negative predictive value (98.8%) and negative likelihood ratio close to 0 or 0.04, and if the dipstick does not detect nitrite and leukocyte, the diagnosis of urinary tract infection is highly unlikely (