C. trachomatis may raise risk for precancerous anal lesions in patients with HIV
Study findings showed that patients with HIV who are coinfected with HPV and Chlamydia trachomatis face a substantially increased risk for high-grade anal intraepithelial neoplasia, suggesting that C. trachomatis may enhance the oncogenic potential of HPV, researchers said.
“Anal cancer has become one of the leading causes of non-AIDS defining cancers among people living with HIV (PLWH), especially among men who have sex with men (MSM). Oncogenic strains of HPV are the major etiological agents linked to the development of high-grade anal intraepithelial neoplasia (HGAIN), the precursor lesion of anal cancer. However, other contributory factors should be implicated to explain that only a small proportion of patients infected with these high-risk HPV genotypes develop HGAIN,” Mar Masiá, MD, from the infectious diseases unit at the General Hospital of Elche and Miguel Hernández University in Alacant, Spain, told Infectious Disease News.
“Besides HPV, coinfection with other sexually transmitted pathogens, and particularly with Chlamydia, is highly frequent among HIV-positive MSM. In HPV-infected women, coinfection with Chlamydia trachomatis (CT) has been associated with cervical cancer, but limited data are available about the role of Chlamydia trachomatis in anal lesions in men.”
Masiá and colleagues conducted a prospective study in an HIV cohort at the General Hospital of Elche to assess the relationship between STIs, including HPV, and HGAIN in HIV-positive MSM. According to the study, participants underwent high-resolution anoscopy for anorectal swab collection to investigate STIs and for anal biopsy.
In total, 145 participants were included in the study, and 35 were diagnosed with HGAIN. According to Masiá and colleagues, 26.2% of participants were infected with HPV16, the most prevalent HPV genotype identified in the study, and 9% of asymptomatic participants were coinfected with CT. Masiá explained that coinfection with CT and HPV16 substantially increased the risk for HGAIN (OR = 31; 95% CI, 4.34-221.71) compared with either infection alone. Additionally, the researchers found that HPV53 and HPV70, two genotypes not yet characterized as high-risk, were associated with HGAIN and persisted in all the participants with recurrent lesions.
“The probability of high-grade anal dysplasia increases when infection with both Chlamydia and HPV16 coexist,” Masiá concluded. “Because of the high and growing frequency of infection with Chlamydia in MSM and the paucity of related symptoms, as observed in our cohort, screening and eventual therapy for this pathogen should be considered among measures to prevent anal cancer. In addition to the classical high-risk HPV genotypes, HPV53 and HPV70 could also be linked with the development of anal dysplasia and, consequently, anal cancer.” – by Caitlyn Stulpin
Disclosures: Masiá reports receiving personal feed from Janssen-Cilag, ViiV Healthcare and Gilead Sciences. Please see the study for all other authors’ disclosures.