Prevalence of Chlamydia infection among women visiting a gynaecology outpatient department: evaluation of an in-house PCR assay for detection of Chlamydia trachomatis

Abstract

BackgroundScreening women for Chlamydia trachomatis infection in developing countries is highly desirable because of asymptomatic infection. The existing diagnostic methods in developing countries are not effective and their sensitivity fall below 45.0% which leads to further spread of infection. There is an urgent need for improved and cost effective diagnostic tests that will reduce the burden of sexually transmitted infections in the developing world.MethodsPrevalence of C. trachomatis infection among women visiting gynaecology department of Hindu Rao hospital in Delhi, India was determined using Roche Amplicor Multi Well Plate kit (MWP) as well as using in-house PCR assay. We used 593 endocervical swabs for clinical evaluation of the in-house developed assay against Direct Fluorescence Assay (DFA; Group I n = 274) and Roche Amplicor MWP kit (Group II, n = 319 samples) and determined the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of the in-house developed assay.ResultsWe detected 23.0% positive cases and there was a higher representation of women aged 18-33 in this group. An in-house PCR assay was developed and evaluated by targeting unique sequence within the gyrA gene of C. trachomatis. Specificity of the reaction was confirmed by using genomic DNA of human and other STI related microorganisms as template. Assay is highly sensitive and can detect as low as 10 fg of C. trachomatis DNA. The resolved sensitivity of in-house PCR was 94.5% compared with 88.0% of DFA assay. The high specificity (98.4%) and sensitivity (97.1%) of the in-house assay against Roche kit and availability of test results within 3 hours allowed for immediate treatment and reduced the risk of potential onward transmission.ConclusionsThe in-house PCR method is cost effective (~ 20.0% of Roche assay) and hence could be a better alternative for routine diagnosis of genital infection by C. trachomatis to facilitate improved screening and treatment management.

Prevalence of cases of Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum and Chlamydia trachomatis in women with no gynecologic complaints

“…Codes et al [22] found a prevalence of 6.9 % of Chlamydia in asymptomatic women. Patel et al [23] found a large prevalence of 23 % of Chlamydia in woman visiting gynecology department of Hindu Rao hospital in Delhi. The authors attribute the high prevalence to better detection procedures.…”

Prevalência de Chlamydia trachomathis em amostras endocervicais de mulheres em São Paulo e Santa Catarina pela PCR

“…Portanto, visto que é um agente com alta prevalência no mundo, faz-se necessário o emprego de metodologias de diagnóstico e monitoria adequada da CT (1) . Entre a vasta gama de metodologias, a mais utilizada é a identificação por métodos sorológicos (9,28) , no entanto, é fundamental o emprego de metodologias da Biologia Molecular na identificação, principalmente pelo material genético, do agente, entre elas destaca-se a PCR (2,6,8,10,12,22,25,27,(30)(31)(32) , por possuir eficácia e sensibilidade de 100%, enquanto o imunoensaioenzimático, por exemplo, possui sensibilidade de 58,8% e especificidade de 100% (14) .…”

Detection of Chlamydia trachomatis by Immunological and Genetic Methods in Female Sex Workers and the Local Female Population of Reproductive Age in Mymensingh, Bangladesh

“…The largest number of new cases (42.89 million) occurred in the region of South and Southeast Asia, accounting for 47z of the total infected cases. The prevalence of C. trachomatis infection diagnosed by polymerase chain reaction (PCR) using genital specimens among women in India was reportedly 23z-32z (2,3). In Bangladesh, there have been some studies on the prevalence of C. trachomatis infections, which examined only female sex workers (FSW) in Dhaka or other cities (4)(5)(6)(7).…”