Comparison of Two PCR Assays for Trichomonas vaginalis

Abstract

PCR is known to be the most sensitive method for diagnosing Trichomonas vaginalis infections. This study aimed to compare the sensitivity of a PCR assay for trichomoniasis (HY-PCR) developed in Hanyang University with the use of a Seeplex Ace Detection Kit®, using urine collected from four Korean men with prostatic disease. Overall, HY-PCR was more sensitive than the Seeplex Kit. The use of Chelex 100 is recommended for DNA isolation in order to increase the sensitivity of the PCR test.

Keywords: DNA isolation; PCR; Trichomonas vaginalis.

Fig. 1

Sensitivity of HY-PCR tested with varying numbers of trophozoites (1, 10, 100) of T. vaginalis. (A) Chelex^® 100, (B) QIAamp^® DNA Mini Kit were used for DNA extraction. The PCR product formed a 318 bp band. N, Negative control (DW); 1, 10, 100, number of trichomonads used.

Fig. 2

Comparison between Chelex^® 100 (A) and QIAamp^® DNA Mini Kit (B) as DNA extraction methods for PCR using a Seeplex^® ACE Detection Kit. T. vaginalis trophozoites (1, 10, 100) were added to the urine of a normal male and incubated overnight before DNA extraction. N, negative control (DW); M, marker; arrowhead, T. vaginalis product.

Fig. 3

Two PCR assay systems were used with DNA isolated from the urine of the 4 patients by 2 DNA extraction methods. (A) All 4 urine samples gave positive bands in HY-PCR using DNA extracted with Chelex^®100. (B, C) PCR with Seeplex^® ACE Detection Kit. (B) Only one of the 4 samples gave a positive band with DNA isolated with Chelex^® 100, and (C) none gave positive band with DNA extracted with QIAamp^® DNA Mini Kit. Arrowhead, T. vaginalis.