COMPARISON OF PCR AND CULTURE METHODS TO DETECT LISTERIA MONOCYTOGENES IN VAGINAL SPECIMENS

Background and Aim:Listeria monocytogenes is a facultative-anaerobic Gram-positive bacilli and causes infections such as meningoencephalitis, septicemia and abortion in humans, especially pregnant women. One of the basic problems with this organism is its determine the prevalence and comparison of culture and PCR methods in diagnosis of this organism in vaginal samples.Methods:In this study, 126 vaginal samples were collected from patients hospitalized in hospitals of Sari (North of Iran) based on demographic characteristics including age, education, occupation, history of abortion, stillbirth and preterm labor, type of delivery and contraceptive method. Samples were cultured in Blood agar medium. The bacterial genome was also extracted from vaginal specimens and used in the PCR method using ActA gene amplification.Results:Listeria monocytogenes were detected in 42 (33.3%) samples by PCR method and from 4 (3.1%) samples using culture method. The prevalence of this bacterium in this study was 39%.Conclusion:The results indicate that PCR is a faster, more sensitive and accurate method for diagnosis of listeria monocytogenes in vaginal samples compared with the culture method. Also, using a standard and reliable method, such as PCR, is essential for rapid detection of this bacterium.

Keywords:

Listeria monocytogenes , culture , PCR , laboratory diagnosis