Comparison of urine culture and urine dipstick analysis in diagnosis of urinary tract infection

ABSTRACT

Urine dipstick is a useful and commonly used test because of its rapidity and low cost; however its diagnostic accuracy is debatable. This research was carried out to determine sensitivity, specificity and positive and negative predictive values of nitrite [NIT] and leukocyte esterase [LE] testing in relation to urine culture. This research was conducted on 100 hospitalized patients with clinical signs and symptoms compatible with urinary tract infections [UTI]]. Urine culture and dipstick tests were carried out on urine samples of all patients. Urinalysis LE and NIT studies were performed in fresh and uncentrifuged urine by using a manual urine analyzer [rapignost, Co. Marburg, Germany]. The urine culture was considered as gold standard. Urine cultures were positive in 75 [75%] patients. Dipstick tests of urine were positive in 79[79%] patients. Sensitivity, specificity, positive predictive value [PPV] and negative predictive value [NPV] of Dipstick test were 76%, 12%, 72% and 14% respectively. Although dipstick test of LE and NIT can avoid a large part of the cost incurred by urine culture, any method of urine screen [LE and NIT] shouldn't be substituted for a urine culture in the symptomatic patients in childhood