The Survey of the Turbidity Interference Rate in 24-Hour Urine Protein Measurement before and after Cold Treatment in Centrifuged Samples

Authors
Masoud Mobini
Maryam Asghar Heydari
Mohammad Salehi
Mahmud Gholami
Abstract
Introduction and Aims

Proteinuria means the presence of an excess of serum proteins in the urine that is very important to achieve accurate and reliable results to the physicians. The aim of this study was to evaluate the interference of turbidity in the measurement of 24-hour urine protein before and after cold treatment in turbid centrifuged samples.

Materials and Methods

This experimental study was performed in ACECR (Academic Center for Education, Culture and Research), that was conducted on a random sample of 1000 people in 2015 March to September. The measurement of 24-hour urine protein was performed by using three chloral acetic acid method (TCA) and photometer.

Results

Ten samples (1%) just were turbid after centrifuge. There was a significant difference (P<0.05) between the samples which were turbid after centrifuge and the samples which their turbidity have removed by cold treatment. So that, in some cases the interpretation of the results after cold treatment is quite different with before (the lowest difference was 0.05 and most difference was 0.43).

Conclusion

In order to deposit interfering factors, the urine samples that are taken to measure protein and are turbid after centrifuge should be given cold treatment and centrifuge again.



* Corresponding Author: Iranian Academic Center for Education, Medical Diagnostic Laboratory of ACECR-Razavi Khorasan.

Email: Mohammadsalehi73@gmail.com
Keywords
proteinuria
urine turbid interference rate
24 hour urine protein
treatment
cold temperature
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