[Effect of storage conditions of clinical materials on virological tests results by RT-PCR]

Obtaining a reliable laboratory test result depends on many factors, among which preanalitical factors play a significant role. The aim of this study was to determine the effect of temperature, storage time of samples and number of freezing and thawing cycles on the results of tests carried out by RT-PCR. The study was conducted in a model of measles virus (RNA). The results revealed that: (1) Samples of clinical material (serum, cerebrospinal fluid, urine) for testing by RT-PCR can be stored for at least 5 days at room temperature or refrigerated and at least 7 days when frozen, (2) Freezing and thawing three times, samples of clinical material does not affect the outcome of the presence of viral RNA, (3) Isolated viral RNA is stable at freezer temperature and can be subjected to at least 20 freeze-thaw cycles without affecting the results.