La circumcisió masculina pot reduir el risc de contraure algunes malalties de transmissió sexual

Uns resultats sorprenents que ara ja gaudeixen d'evidència científica. Mitjançant un estudi multicèntric de més de 1000 dones amb les seves respectives parelles, es va aconseguir quantificar per primer cop la sospita que existia entre la comunitat científica: que la circumcisió masculina s'associa a un menor risc de virus del papiloma humà (VPH) al penis, i un risc menor de càncer de coll d'úter en la seva parella. A més a més, existeix també una forta evidència científica que mostra que aquesta senzilla intervenció quirúrgica redueix la infecció per VIH. Dades molt importants i que han donat suport a estudis observacionals i assajos clínics realitzats a l'Àfrica. De tota manera, els mecanismes que redueixen aquest risc d'infecció per VIH o VPH no es coneixen encara. Existeixen algunes hipòtesis. Per exemple, un possible mecanisme seria que amb l'eliminació del prepuci, s'estan eliminant també les cèl·lules receptores de la infecció, de manera que es redueix l'àrea d'exposició a la infecció. Tot i això, actualment l'Organització Mundial de la Salut (OMS) dóna suport a la introducció de la circumcisió masculina com una de les millors estratègies preventives en homes adults en països d'alt risc que no es poden permetre la implantació d'altres estratègies de prevenció del VIH, del VPH i altres malalties de transmissió sexual.Unos resultados sorprendentes que ahora ya gozan de evidencia científica. Mediante un estudio multicéntrico de más de 1000 mujeres con sus respectivas parejas, se logró cuantificar por primera vez la sospecha que existía entre la comunidad científica: que la circuncisión masculina se asocia a un menor riesgo de Virus del Papiloma Humano (VPH) en el pene, y un menor riesgo de cáncer de cuello de útero en su pareja. Además, existe también una fuerte evidencia científica que muestra que esta sencilla intervención quirúrgica reduce la infección por VIH. Datos muy importantes y que se han apoyado en estudios observacionales y ensayos clínicos realizados en África. De todos modos, los mecanismos que reducen este riesgo de infección por VIH o VPH no se conocen todavía. Existen algunas hipótesis. Por ejemplo, un posible mecanismo sería que con la eliminación del prepucio, se están eliminando también las células receptoras de la infección, de manera que se reduce el área de exposición a la infección. Sin embargo, actualmente la Organización Mundial de la Salud (OMS) apoya la introducción de la circuncisión masculina como una de las mejores estrategias preventivas en hombres adultos en países de alto riesgo que no se pueden permitir la implantación de otras estrategias de prevención del VIH, del VPH y otras enfermedades de transmisión sexual

Human Papillomavirus (HPV) infection in pregnant women and mother-to-child transmission of genital HPV genotypes: a prospective study in Spain

Background: Studies on HPV infection in pregnant women and HPV transmission to the child have yielded inconsistent results. Methods: To estimate mother-to-child HPV transmission we carried out a prospective cohort study that included 66 HPV-positive and 77 HPV-negative pregnant women and their offspring attending a maternity hospital in Barcelona. To estimate HPV prevalence and genotype distribution in pregnancy we also carried out a related screening survey of cervical HPV-DNA detection among 828 pregnant women. Cervical cells from the mother were collected at pregnancy (mean of 31 weeks) and at the 6-week post-partum visit. Exfoliated cells from the mouth and external genitalia of the infants were collected around birth, at the 6-week post-partum visit, and around 3, 6, 12, and 24 months of age. All samples were tested for HPV using PCR. Associations between potential determinants of HPV infection in pregnant women and of HPV positivity in infants were also explored by logistic regression modelling. Results: Overall cervical HPV-DNA detection in pregnant women recruited in the HPV screening survey was 6.5% (54/828). Sexual behavior-related variables, previous histories of genital warts or sexually transmitted infections, and presence of cytological abnormalities were statistically significantly and positively associated with HPV DNA detection in pregnant women recruited in the cohort. At 418 infant visits and a mean follow-up time of 14 months, 19.7% of infants born to HPV-positive mothers and 16.9% of those born to HPV-negative mothers tested HPV positive at some point during infants' follow-up. The most frequently detected genotype both in infants and mothers was HPV-16, after excluding untyped HPV infections. We found a strong and statistically significant association between mother's and child's HPV status at the 6-week post-partum visit. Thus, children of mothers' who were HPV-positive at the post-partum visit were about 5 times more likely to test HPV-positive than children of corresponding HPV-negative mothers (p = 0.02). Conclusion: This study confirms that the risk of vertical transmission of HPV genotypes is relatively low. HPV persistence in infants is a rare event. These data also indicate that vertical transmission may not be the sole source of HPV infections in infants and provides partial evidence for horizontal mother-to-child HPV transmission

El rol de la circuncisión masculina en la infección genital por el virus del papiloma humano

Introducción: El efecto protector de la circuncisión masculina (CM) y la infección genital por el virus del papiloma humano (VPH) y las enfermedades relacionadas no ha sido consistente en todos los estudios. Objetivo: El objetivo de esta tesis ha sido estudiar el rol de la CM en la infección por el VPH genital en los hombres. Metodologia: En primer lugar, se examinó el efecto de la CM en la infección de VPH en el pene mediante revisiones sistemáticas de la literatura para poder evaluar el efecto de la CM con distintos indicadores de la infección por el VPH. En segundo lugar, se evaluó la asociación entre la CM y la prevalencia, la incidencia y la resolución del VPH genital en los hombres en el estudio prospectivo HIM. Con un total de 4074 hombres entre 18-70 años de Brasil, México y los Estados Unidos de América es uno de los estudios más grandes realizado hasta la fecha que permite explorar estas asociaciones. Para la detección de ADN del VPH, se combinaron en una única muestra células exfoliadas del surco coronal/glande, cuerpo del pene y escroto. Resultados: Los resultados del metanálisis muestran una prevalencia global de VPH genital menor entre los hombres circuncidados en comparación a los hombres no circuncidados. En cambio, la CM no está asociada con una reducción de la incidencia o un aumento de la resolución del VPH. La CM no está asociada con una reducción en la prevalencia de las verrugas genitales. Los resultados del estudio HIM indican que la prevalencia de VPH genital es menor entre los hombres circuncidados en comparación a los hombres no circuncidados pero sólo con los tipos de VPH no oncogénicos. La CM no está asociada con la incidencia o la resolución del VPH, excepto para ciertos tipos específicos de VPH. Conclusiones: Esta tesis muestra que no existe una asociación clara entre la CM y las diferentes medidas de la infección por el VPH genital en los hombres. La combinación de diferentes localizaciones del pene y del escroto probablemente limita la capacidad para identificar un efecto de la CM en la infección por el VPH en el pene distal, la zona probablemente más protegida por la eliminación del prepucio.Background: The protective effect of male circumcision (MC) and genital human papillomavirus (HPV) infection and related diseases has not been consistent across all studies. Objective: The purpose of this thesis was to study the association between MC and genital HPV infection in men. Methods: First, we examined the effect of MC on HPV infection in the penis by systematic reviews of the literature to be able to evaluate the effect of MC with different indicators of HPV infection. Second, we evaluated the association between MC and the prevalence, incidence and clearance of genital HPV infection in men in the prospective HIM study. A total of 4074 men between 18-70 years were enrolled in a study conducted in Brazil, Mexico and the United States of America. It is one of the largest studies conducted to date to explore these associations. Exfoliated cell specimens from the coronal sulcus/glans, penile shaft, and scrotum were collected and combined into one sample per person for HPV DNA detection. Results: The meta-analysis results show an overall reduction in the prevalence of genital HPV infection among circumcised men compared to uncircumcised men. In contrast, MC is not associated with the incidence and clearance of genital HPV infection. MC is not associated with a reduction in the prevalence of genital warts. The results of the HIM study indicate that the prevalence of genital HPV is lower among circumcised men compared to uncircumcised men but only with non-oncogenic HPV types. MC is not associated with the incidence and clearance of genital HPV infection, except for certain HPV types. Conclusions: This thesis shows that the association between MC and different measures of genital HPV infection in men is no clear. The combination of different locations of the penis and scrotum probably limits the ability to identify an effect of MC on HPV infection in the distal penis, the area most likely protected by removal of the foreskin

El Rol de la circuncisión masculina en la infección genital por el virus del papiloma humano /

Introducción: El efecto protector de la circuncisión masculina (CM) y la infección genital por el virus del papiloma humano (VPH) y las enfermedades relacionadas no ha sido consistente en todos los estudios. Objetivo: El objetivo de esta tesis ha sido estudiar el rol de la CM en la infección por el VPH genital en los hombres. Metodologia: En primer lugar, se examinó el efecto de la CM en la infección de VPH en el pene mediante revisiones sistemáticas de la literatura para poder evaluar el efecto de la CM con distintos indicadores de la infección por el VPH. En segundo lugar, se evaluó la asociación entre la CM y la prevalencia, la incidencia y la resolución del VPH genital en los hombres en el estudio prospectivo HIM. Con un total de 4074 hombres entre 18-70 años de Brasil, México y los Estados Unidos de América es uno de los estudios más grandes realizado hasta la fecha que permite explorar estas asociaciones. Para la detección de ADN del VPH, se combinaron en una única muestra células exfoliadas del surco coronal/glande, cuerpo del pene y escroto. Resultados: Los resultados del metanálisis muestran una prevalencia global de VPH genital menor entre los hombres circuncidados en comparación a los hombres no circuncidados. En cambio, la CM no está asociada con una reducción de la incidencia o un aumento de la resolución del VPH. La CM no está asociada con una reducción en la prevalencia de las verrugas genitales. Los resultados del estudio HIM indican que la prevalencia de VPH genital es menor entre los hombres circuncidados en comparación a los hombres no circuncidados pero sólo con los tipos de VPH no oncogénicos. La CM no está asociada con la incidencia o la resolución del VPH, excepto para ciertos tipos específicos de VPH. Conclusiones: Esta tesis muestra que no existe una asociación clara entre la CM y las diferentes medidas de la infección por el VPH genital en los hombres. La combinación de diferentes localizaciones del pene y del escroto probablemente limita la capacidad para identificar un efecto de la CM en la infección por el VPH en el pene distal, la zona probablemente más protegida por la eliminación del prepucio.Background: The protective effect of male circumcision (MC) and genital human papillomavirus (HPV) infection and related diseases has not been consistent across all studies. Objective: The purpose of this thesis was to study the association between MC and genital HPV infection in men. Methods: First, we examined the effect of MC on HPV infection in the penis by systematic reviews of the literature to be able to evaluate the effect of MC with different indicators of HPV infection. Second, we evaluated the association between MC and the prevalence, incidence and clearance of genital HPV infection in men in the prospective HIM study. A total of 4074 men between 18-70 years were enrolled in a study conducted in Brazil, Mexico and the United States of America. It is one of the largest studies conducted to date to explore these associations. Exfoliated cell specimens from the coronal sulcus/glans, penile shaft, and scrotum were collected and combined into one sample per person for HPV DNA detection. Results: The meta-analysis results show an overall reduction in the prevalence of genital HPV infection among circumcised men compared to uncircumcised men. In contrast, MC is not associated with the incidence and clearance of genital HPV infection. MC is not associated with a reduction in the prevalence of genital warts. The results of the HIM study indicate that the prevalence of genital HPV is lower among circumcised men compared to uncircumcised men but only with non-oncogenic HPV types. MC is not associated with the incidence and clearance of genital HPV infection, except for certain HPV types. Conclusions: This thesis shows that the association between MC and different measures of genital HPV infection in men is no clear. The combination of different locations of the penis and scrotum probably limits the ability to identify an effect of MC on HPV infection in the distal penis, the area most likely protected by removal of the foreski

Human Papillomavirus (HPV) infection in pregnant women and mother-to-child transmission of genital HPV genotypes : a prospective study in Spain

Background: Studies on HPV infection in pregnant women and HPV transmission to the child have yielded inconsistent results. Methods: To estimate mother-to-child HPV transmission we carried out a prospective cohort study that included 66 HPV-positive and 77 HPV-negative pregnant women and their offspring attending a maternity hospital in Barcelona. To estimate HPV prevalence and genotype distribution in pregnancy we also carried out a related screening survey of cervical HPV-DNA detection among 828 pregnant women. Cervical cells from the mother were collected at pregnancy (mean of 31 weeks) and at the 6-week post-partum visit. Exfoliated cells from the mouth and external genitalia of the infants were collected around birth, at the 6-week post-partum visit, and around 3, 6, 12, and 24 months of age. All samples were tested for HPV using PCR. Associations between potential determinants of HPV infection in pregnant women and of HPV positivity in infants were also explored by logistic regression modelling. Results: Overall cervical HPV-DNA detection in pregnant women recruited in the HPV screening survey was 6.5% (54/828). Sexual behavior-related variables, previous histories of genital warts or sexually transmitted infections, and presence of cytological abnormalities were statistically significantly and positively associated with HPV DNA detection in pregnant women recruited in the cohort. At 418 infant visits and a mean follow-up time of 14 months, 19.7% of infants born to HPV-positive mothers and 16.9% of those born to HPV-negative mothers tested HPV positive at some point during infants' follow-up. The most frequently detected genotype both in infants and mothers was HPV-16, after excluding untyped HPV infections. We found a strong and statistically significant association between mother's and child's HPV status at the 6-week post-partum visit. Thus, children of mothers' who were HPV-positive at the post-partum visit were about 5 times more likely to test HPV-positive than children of corresponding HPV-negative mothers (p = 0.02). Conclusion: This study confirms that the risk of vertical transmission of HPV genotypes is relatively low. HPV persistence in infants is a rare event. These data also indicate that vertical transmission may not be the sole source of HPV infections in infants and provides partial evidence for horizontal mother-to-child HPV transmission

Male circumcision and prevalence of genital human papillomavirus infection in men : a multinational study

Background: Accumulated evidence from epidemiological studies and more recently from randomized controlled trials suggests that male circumcision (MC) may substantially protect against genital HPV infection in men. The purpose of this study was to assess the association between MC and genital HPV infection in men in a large multinational study. Methods: A total of 4072 healthy men ages 18-70 years were enrolled in a study conducted in Brazil, Mexico, and the United States. Enrollment samples combining exfoliated cells from the coronal sulcus, glans penis, shaft, and scrotum were analyzed for the presence and genotyping of HPV DNA by PCR and linear array methods. Prevalence ratios (PR) were used to estimate associations between MC and HPV detection adjusting for potential confounders. Results: MC was not associated with overall prevalence of any HPV, oncogenic HPV types or unclassified HPV types. However, MC was negatively associated with non-oncogenic HPV infections (PR 0.85, 95% confident interval: 0.76-0.95), in particular for HPV types 11, 40, 61, 71, and 81. HPV 16, 51, 62, and 84 were the most frequently identified genotypes regardless of MC status. Conclusions: This study shows no overall association between MC and genital HPV infections in men, except for certain non-oncogenic HPV types for which a weak association was found. However, the lack of association with MC might be due to the lack of anatomic site specific HPV data, for example the glans penis, the area expected to be most likely protected by MC