Chlamydia trachomatis as a probable cofactor in human papillomavirus infection in aboriginal women from northeastern Argentina

Objectives: High-risk types of human papillomavirus (HPV) are strongly associated with cervical cancer (CC), and Chlamydia trachomatis (CT), the most frequent sexually transmitted bacterial infection (STBI) worldwide, seems to be a risk factor for HPV infection and for CC. It is also known that both agents are more prevalent in vulnerable communities where lack of adequate primary health care is a cause for concern. The aim of this work was to determine the impact of CT and HPV infections in women belonging to an isolated aboriginal population (Pilaga community) from a poor region in Northern Argentina (province of Formosa). For this purpose, a cross-sectional study was performed in all sexually active Pilaga women, who attended a local community-based gynecological health screening project. The polymerase chain reaction (PCR) method on a cervical brush specimen was used to detect both agents. Results: A total of 227 women (20 percent of the total female population of the Pilaga community) were studied and the overall prevalence was 26.4 percent for CT, 46.7 percent for HPV and 16.3 percent for concurrent infection. CT infection was higher in HPV DNA positive (34.2 percent) than in HPV DNA negative women (19 percent; OR: 2.22/95 percent CI = 1.16-4.28 / p = 0.009) and the most prevalent HPV types were HPV-16 (19.4 percent), 6 and 18 (5.3 percent), 58 (3.5 percent) and 33 (3.1 percent). Conclusions: The prevalence of CT and HPV observed in Pilaga women are among the worst registered in Latin America. Also, data collected suggest that chlamydial infection may play an important role in the natural history of HPV infection. On this respect, we propose that the association between these two agents seems to be more related to a mutual potentiation than to the fact that they share a common route of transmission.

Chlamydia trachomatis as a probable cofactor in human papillomavirus infection in aboriginal women from northeastern Argentina.

OBJECTIVES: High-risk types of human papillomavirus (HPV) are strongly associated with cervical cancer (CC), and Chlamydia trachomatis (CT), the most frequent sexually transmitted bacterial infection (STBI) worldwide, seems to be a risk factor for HPV infection and for CC. It is also known that both agents are more prevalent in vulnerable communities where lack of adequate primary health care is a cause for concern. The aim of this work was to determine the impact of CT and HPV infections in women belonging to an isolated aboriginal population (Pilaga community) from a poor region in Northern Argentina (province of Formosa). For this purpose, a cross-sectional study was performed in all sexually active Pilaga women, who attended a local community-based gynecological health screening project. The polymerase chain reaction (PCR) method on a cervical brush specimen was used to detect both agents. RESULTS: A total of 227 women (20% of the total female population of the Pilaga community) were studied and the overall prevalence was 26.4% for CT, 46.7% for HPV and 16.3% for concurrent infection. CT infection was higher in HPV DNA positive (34.2%) than in HPV DNA negative women (19%; OR: 2.22/95% CI = 1.16-4.28 / p = 0.009) and the most prevalent HPV types were HPV-16 (19.4%), 6 and 18 (5.3%), 58 (3.5%) and 33 (3.1%). CONCLUSIONS: The prevalence of CT and HPV observed in Pilaga women are among the worst registered in Latin America. Also, data collected suggest that chlamydial infection may play an important role in the natural history of HPV infection. On this respect, we propose that the association between these two agents seems to be more related to a mutual potentiation than to the fact that they share a common route of transmission.

[Chlamydia trachomatis and papillomavirus infection in women with cytohistological abnormalities in uterine cervix]. / Infección por Chlamydia trachomatis y papilomavirus en mujeres con alteraciones citohistológicas de cuello uterino.

The presence of Chlamydia trachomatis and human papillomavirus (HPV) was evaluated by PCR technique in 189 sexually active women, between 15 and 58 years old, with cytological abnormalities in their uterine cervical epithelium and belonging to a region of Argentina with high incidence of cervical cancer. Risk factors in relation to chlamydial infection were also analyzed. Total prevalence for C. trachomatis infection was 24.9%, but there was a significant difference between prevalence in low socio-economical level (32.9%) and high or medium socio-economical level (17.7%). Total prevalence for DNA of HPV was 52.9%, but women infected with C. trachomatis showed a higher risk for viral infection than non-infected ones (OR = 2.27 / CI 95% = 1.10-4.73), with statistical significant difference (p = 0.016).

Human papillomavirus genotypes in women with cervical cytological abnormalities from an area with high incidence of cervical cancer.

It has been well demonstrated the relationship between the infection with high-risk human papillomavirus (HPVs) genotypes and cervical cancer. In Northeastern Argentina a high incidence of this pathology has been described and therefore a high prevalence of HPV infection is expected. In order to identify HPV genotypes associated with malignant and pre-malignant cervical lesions present in the area, 53 ecto-endo cervical cell specimens obtained from women with cytohistological alterations were studied by a PCR-RFLP technique. Out of 53 patients, 34 (64.2%) were positive for HPV infection, being HPV-16 (32.3%) the most frequently found genotype, followed by HPV-58 (14.7%), -6, -18 and -45 (5.9%), -33, -52, -53, -54, -56, -66, -MM4 and -LVX100 (2.9%). Also 5 cases of infection caused by multiple genotypes were found, which corresponded to 14.7% of the positive cases. Results indicate that besides HPV-16 and -18, the most prevalent high-risk HPV genotypes worldwide, others like -45 and -58 as well as co-infection cases are frequent between women of Northeastern Argentina, and a particular attention should be paid to this circumstance because it could be an epidemiological feature of regional importance and a useful information for a future vaccination program.

Human papillomavirus genotypes in women with cervical cytological abnormalities from an area with high incidence of cervical cancer

La relación entre la infección por los virus papiloma humanos (HPVs) de alto riesgo y el cáncer de cuello de útero ha sido bien demostrada. En el Nordeste de Argentina se observa una alta incidencia de esta patología y en consecuencia se estima una alta prevalencia de infección por HPV. A fin de identificar los genotipos de HPV presentes en el área, asociados a casos de lesiones malignas y premalignas de cuello de útero, se estudiaron 53 muestras ecto-endo cervicales de mujeres con alteraciones citohistológicas residentes permanentes de las ciudades de Resistencia y Corrientes. De las 53 pacientes estudiadas, 34 resultaron positivas para HPV (64.2 por ciento), correspondiendo la mayor frecuencia a HPV-16 (32.3 por ciento), seguido por HPV-58 (14.7 por ciento), HPV-6, -18 y -45 (5.9 por ciento), -33, -52, -53, -54, -56, -66, -MM4 y -LVX100 (2.9 por ciento). Además, se encontraron 5 casos de infecciones mixtas causadas por mas de un genotipo, lo que resulta de importancia ya que representan el 14.7 por ciento del total de los casos positivos. Los resultados demuestran que, además de HPV-16 y -18 que son los genotipos de alto riesgo de mayor prevalencia a nivel mundial, otros como el HPV-45 y -58 y los casos de infecciones múltiples son frecuentes en mujeres del nordeste argentino, lo que podría constituir un rasgo epidemiológico de importancia regional y ser de utilidad en el futuro en los programas de vacunación.