Original Articles

Impact of Pre-analytic Practices on Diagnostic Accuracy of Urine Cultures-A Retrospective Study

Abstract

Background:   Several pre-analytic factors adversely affect the diagnostic accuracy of urine cultures. The aim of our study is to identify and evaluate preanalytic practices associated with urine specimens and assess their impact on the accuracy of urine culture microbiology.

Methods:   A retrospective study was conducted from January 2019 to June 2019 on urine cultures showing discrepant results. This included 225 patients whose culture showed growth of a single pathogen with no pus cells in the Gram stain. The details regarding the sample type, repeat cultures sent, and complete urine analysis (CUE), were analyzed.

Results:   Of the 225 samples, 208(93.4%) were clean catch and 17 (3.1%) were catheter catch. Of 17 patients with catheter catch, urine culture and CUE were done in 12 (70.5%) patients. CUE was normal in 10 (83.3%) of the patients. The culture was sent within 1-7 days in 12 (70.5%) patients. Of 208 patients with clean catch urine culture, CUE was done in 174 (83.6%) patients. CUE was normal in 162 (93.1%) of patients. The culture was sent in 1-7 days in 146 (70.1%) patients. Escherichia coli was the predominant organism isolated in clean and catheter catch. Of 450 polymicrobial cultures, Gram stain showed pus cells with/without organisms in 66(14.6%) of cases.

Conclusion:   In the majority of the urine cultures, there was no correlation between microscopy and culture. The samples would have been sent without proper indication and collected improperly. A positive urine culture alone is insufficient for the diagnosis of UTI, it has to be correlated with microscopy and clinical history.

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IssueVol 13 No 3 (2025) QRcode
SectionOriginal Articles
Keywords
Asymptomatic bacteriuria Complete urine analysis Contamination.
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How to Cite
1.
Sudhaharan S, Pamidimukkala U, J S, Naaz S. Impact of Pre-analytic Practices on Diagnostic Accuracy of Urine Cultures-A Retrospective Study. J Med Bacteriol. 2025;13(3):1-7.