مقايسه كاربرد كشت ادرار با رنگ آميزي گرم ادرار در تشخيص عفونت هاي ادراري

Comparison of urine cultures and gram stained smears of urine in diagnosis of urinary tract infections

Background: Different methods are used for diagnosis of urinary tract infections (UTI), however, they have different specificity, sensitivity and time consuming procedures. Objective: To evaluate and comparing the urine culture results with gram stained smears of urine in diagnosis of urinary tract infections. Methods: This research was conducted on 100 hospitalized patients with clinical signs and symptoms compatible with UTI. Urine cultures and gram staining were performed on urine samples of all patients. Findings: Urine culture was positive in 75 (75%) of patients. Gram stained smears on urine sediments were positive in 68 (68%) of patients. Sensitivity, specificity and positive predictive value of gram staining were 85%, 84% and 94% respectively. Conclusion: Gram stained smears of urine, as a diagnostic assay for UTI, is not as sensitive as urine cultures, but it takes only a few minutes to be performed, comparing with urine culture which takes several days.