Non-detection of Chlamydia trachomatis infection by polymerase chain reaction in pregnant Iranian women

Abstract

Chlamydia trachomatis is the most common cause of sexually transmitted infection. In 75% of women and 50% of men infection is asymptomatic. According to World Health Organization reports, the number of new genital infections with Chlamydia trachomatis reaches 100 million annually. The sensitivity and specificity of nacid amplification tests are 95% and 99%, respectively. Urine samples can provide a non-invasive method of testing for the detection of Chlamydia trachomatis by polymerase chain reaction (PCR). The aim of this study was to evaluate the prevalence of Chlamydia trachomatis infection in pregnant women referred to a teaching hospital affiliated to Shiraz University of Medical Sciences. Urine samples were obtained from 210 pregnant women and investigated microscopically and macroscopically by urinalysis. Precipitants were also used for DNA extraction and PCR test for detecting Chlamydia trachomatis. Among 210 urine specimens from women aged 15-39 years, none were positive for Chlamydia trachomatis by PCR. In spite of the high sensitivity and specificity of PCR, and the elimination of inhibitory effects on PCR test, no pregnant woman was positive for Chlamydia trachomatis. Here, we suggest that a larger sample should be studied and other sensitive methods could also be used in the future.

Rapid and visual Chlamydia trachomatis detection using loop-mediated isothermal amplification and hydroxynaphthol blue

“…; Hassanzadeh et al . ). This included a minimum of two confirmed PCR‐GE results, and then ompA sequencing.…”

“…; Hassanzadeh et al . ). Polymerase chain reaction was performed in a 25 μ l reaction mixture containing 100 ng of template DNA, 0·3 μ mol l −1 of forward and reverse primers, and 12·5 μ l EmeraldAmp ® GT PCR Master Mix (TakaRa Bio Inc., Shiga, Japan).…”

“…; Hassanzadeh et al . ). For conventional C. trachomatis PCR detection, using the DNA coding region of an outer membrane protein A gene ( ompA ) and visualization of the result by agarose gel electrophoresis (GE) is widely accepted, and sequencing of this region further allows classification of C. trachomatis into 19 serovars (Gomes et al .…”

“…; Hassanzadeh et al . ; CDC ). However, ompA PCR–GE is inappropriate for point‐of‐care (POC) as a high‐priced thermal cycler and electrophoresis equipment are required, carcinogenic ethidium bromide may be used, and the process takes 3·5–4 h (3–3·5 h for PCR and 0·5 h for GE).…”

“…A polymerase chain reaction (PCR) has been established elsewhere for superior detection limit and specificity for many disease pathogens, including Chlamydia (Bandea et al 2008;Ficarra et al 2008;Hassanzadeh et al 2012). For conventional C. trachomatis PCR detection, using the DNA coding region of an outer membrane protein A gene (ompA) and visualization of the result by agarose gel electrophoresis (GE) is widely accepted, and sequencing of this region further allows classification of C. trachomatis into 19 serovars (Gomes et al 2006;Hassanzadeh et al 2012;CDC 2014). However, ompA PCR-GE is inappropriate for point-of-care (POC) as a high-priced thermal cycler and electrophoresis equipment are required, carcinogenic ethidium bromide may be used, and the process takes 3Á5-4 h (3-3Á5 h for PCR and 0Á5 h for GE).…”