INFLUENCE OF STORAGE CONDITIONS AND PRESERVATIVES ON URINALYSIS

¹Post Graduate Student, Department of Pathology, Mahatma Gandhi Mission Medical College
²Professor and Head of Department of Pathology, Mahatma Gandhi Mission Medical College
³Post Graduate Student, Department of Pathology, Mahatma Gandhi Mission Medical College
⁴Associate Professor, Department of Pathology, Mahatma Gandhi Mission Medical College
⁵Post Graduate Student, Department of Pathology, Mahatma Gandhi Mission Medical College

ABSTRACT:
Introduction: Urinalysis is very susceptible to pre-analytical issues, one of which arises due to improper or no preservation of urine samples before analysis. Thymol as a preservative because of its antimicrobial property has the advantage of preserving glucose and sediments well. The current study is to evaluate how different concentrations of preservative (thymol) used for storage of urine samples affected the outcome of urine analyses. Aim and Objective: To evaluate how refrigeration and use of preservative (thymol) for storage of urine samples affected the outcome of urine analysis. Material and methods: Spot urine samples were collected from 507 volunteers. Each fresh sample of urine was divided into three 10 ml aliquots, one without preservative, one with 1 drop of thymol and one with 2 drops of thymol. Each urine sample was analysed immediately after collection (0 hour) and after 24 hours. Results: Sugars were best preserved with the use of thymol and that specific gravity, urine protein, occult blood, BS/BP and urine ketones measured after 24 hours were similar to those at 0 hour when samples were stored at low temperature as well as with the use of thymol. Conclusion: Antibacterial preservatives like thymol can be recommended as preservatives for urine samples taking more than 2 hours. Ideally, the samples can be stored at 4 °C without any preservatives.

KEYWORDS: Thymol, preservatives, urinalysis.