High prevalence of hpv multiple genotypes in women with persistent chlamydia trachomatis infection

Background: Chlamydia trachomatis interaction with HR-HPV types has highlighted a central role in cervical cancer development. The aim of this study was to investigate HPV prevalence and genotypes distribution in women at risk for C. trachomatis infection and negative for intraepithelial lesion or malignancy. Methods: 1071 cervical swabs were tested for C. trachomatis by Real Time PCR and genotyping by ompA gene sequencing. Additionally, a quantitative Real time-PCR was performed to assess the expression of the C. trachomatis Hsp60–encoding gene (Ct604 portion), linked to a persistent status of infection. HPV infection and genotypes was investigated in C. trachomatis positive women using Luminex technology. Results: C. trachomatis infection was detected in 53 out of 1071 (4.5%) samples, of which the 53% resulted positive for Hsp60 gene expression. The overall prevalence of HPV infection in C. trachomatis positive samples was of 60.4% (32/53): in 37.5% of samples was present a single genotype, while multiple genotypes infections were found in the 62.5% of them. Among women with a C. trachomatis chronic infection, 68% were HPV co-infected and the 79% showed multiple genotypes. Should be noted that levels of C. trachomatis Hsp60 expression in HPV co-infected women were significantly lower compared to women infected only with C. trachomatis. The C. trachomatis serotype F was found in the majority of samples, independently of HPV infection. Conclusions: A high prevalence of HPV multiple infections have been found in young women affected with a C. trachomatis chronic infection. These observations suggested that the expression of CHSP60-1, interfering with both apoptotic and cellular senescence pathways, may promote a favourable local microenvironment for HPV infection. Keywords: Human papillomavirus, Chlamydia trachomatis, HPV multiple genotypes, Hsp60 RNA persistent infectio