Nergiz ZORBOZAN, İlker AKARKEN, Orçun ZORBOZAN

Mikroskobik idrar analizini öngörmede idrar strip testinin performansı

Amaç: Çalışmanın amacı, manuel mikroskopik idrar analizi öngörmek için idrar strip analizinin performansını değerlendirmektir. Yöntem: İdrar yolu enfeksiyonu (İYE) şüphesi olan hastalardan alınan ve hem mikroskopik hem de strip analizi yapılan idrar örnekleri çalışmaya dahil edildi. Eritrosit strip (Erit-S) ve lökosit strip (Lök-S) testlerinin “eser”, “1+”, “2+”, “3+” kestirim değerleri için duyarlılık, özgüllük, pozitif ve negatif olabilirlik oranları (LR+, LR-), test öncesi ve sonrası şans, test sonrası olasılık değerleri hesaplandı. Koşullu olasılığı belirlemek için Bayes teoremi kullanıldı. ROC eğrisinin altındaki alan (AUC) hesaplandı. Bulgular: Lök-S ve Erit-S için AUC sırası ile 0,923 ve 0,975 olarak bulundu. Lök-S testi “1+”, Erit-S testi “eser” kestirim değerinde yeterli duyarlılık ve özgüllükteydi (>%80). LR+ değerine göre Lök-S “3+” kestirim değerinde, Erit-S tüm kestirim değerlerinde; LR- değerine göre Lök-S eser, Erit-S eser ve “1+” kestirim değerlerinde post-test olasılıkta anlamlı farklılık sağladı (

The performance of the urine strip test for predicting microscopic urine analysis

Objective: The aim of the study is to evaluate the performance of urine strip analysis for predicting manual microscopic urine analysis. Methods: Urine samples, which were ordered from patients with suspected urinary tract infection (UTI), and which were analyzed with both microscopic and strip analysis, were included in the study. Sensitivity, specificity, positive and negative likelihood ratios (LR +, LR-), pre- and post-test odds and post-test probability for cut-off values of “trace”, “1+”, “2+”, “3+” of erythrocyte-strip (Eryth-S) and leucocyte-strip (Leuc-S) tests were calculated. Bayes theorem was used to determine conditional probability. Area under curve (AUC) of ROC was calculated. Results: The AUC for Leuc-S and Eryth-S was 0.923 and 0.975, respectively. The Leuc-S test in “1+” and Eryth-S test in “trace” cut-off value had adequate sensitivity and specificity (>80%). Leuc-S of “3+” and Eryth-S of all cut-off values for LR+ value; Leuc-S of “trace” and Eryth-S of “trace” and “1+” for LR- value were significantly different for posttest probability(

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