Distribution of human papillomavirus genotypes in women with cervical alterations from north Argentina.

BACKGROUND: Cervical cancer remains a major public health problem in northern Argentina, showing the highest mortality rate in the country (approximately 22 cases/100000 women). OBJECTIVE: The aim of this study was to provide epidemiological data on the prevalence and type distribution of human papillomavirus (HPV) in women with pre-neoplastic lesions before the massive introduction of HPV vaccination in the country. MATERIALS AND METHODS: Exfoliated cervical cells were collected to screen for HPV using the widely known MY09/11 PCR, followed by the restriction fragment-length polymorphism (RFLP) technique from a total of 714 women with previously diagnosed atypical squamous cells of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (LG-SIL) and high-grade squamous intraepithelial lesion (HG-SIL). RESULTS: Overall HPV prevalence was 48.2% in ASCUS (24 different HPV types detected), 66.5% in LG-SIL (37 HPV types detected) and 82.6% in HG-SIL (16 HPV types detected). HPV-16 was the most prevalent type among all cases. With respect to multiple HPV infections, 9.6% were observed in ASCUS, 14.3% in LG-SIL and 11.4% in HG-SIL. CONCLUSION: The major strength of our study is the assessment of a large series of women with cytological alterations in this region. The information attained will be useful as a regional baseline for future epidemiological vigilance, in the context of the national HPV vaccination program.

Características clínico-demográficas y tipificación del virus de papiloma humano en mujeres paraguayas con citologías negativas para lesión escamosa intraepitelial / Clinical-demographic characteristics and typification of the human papilloma virus in Paraguayan women with negative citology for squamous intraepithelial lesion

Paraguay posee una alta tasa de incidencia de cáncer de cuello uterino de 35/100.0000 mujeres en el año 2008 y el virus de papiloma humano (HPV) es su agente causal. La planificación de medidas de prevención puede ser beneficiada con conocimientos sobre los tipos virales, por ello, el objetivo de este estudio fue determinar características clínico-demográficas y los tipos de HPV presentes en mujeres con citología negativa para lesión escamosa intraepitelial. Estudio de corte transverso con componente analítico en 207 mujeres con citología negativa para lesión escamosa intraepitelial provenientes de centros de salud de Asunción. La tipificación fue realizada por reacción en cadena de la polimerasa utilizando cebadores MY09/11 y GP5/GP6, seguida de polimorfismo de longitud de fragmentos de restricción e hibridación lineal reversa, respectivamente. La asociación entre HPV y las características clínico-demográficas fue determinada por análisis de Chi cuadrado (EpiInfo versión 3,2). Se detectó alta frecuencia de HPV (21%), siendo el tipo predominante HPV 16 (4,3%) seguido de HPV 58/31 (2,4% cada uno). Se observó asociación entre la presencia de HPV y la edad (p=0,0002), detectándose mayor frecuencia de HPV en mujeres menores a 30 años, la cual, disminuyó al aumentar la edad, presentando un ligero aumento en mujeres de 60 años o más. En conclusión, los datos muestran una alta frecuencia de HPV y HPV 16 en mujeres menores a 30 años con citología negativa y sugieren la necesidad de realizar control posteriormente, a fin de identificar las infecciones persistentes que podrían causar lesión de cuello uterino

Distribution of human papillomavirus genotypes in Paraguayan women according to the severity of the cervical lesion.

The incidence of cervical cancer in Paraguay is among the highest in the world. This study aimed to determine the distribution of human papillomavirus (HPV) genotypes in Paraguayan women, according to the severity of the cervical lesion. This cross-sectional study included 207 women without a squamous intraepithelial lesion, 164 with low-grade squamous intraepithelial lesions, 74 with high-grade squamous intraepithelial lesions, and 41 with cervical cancer. Type-specific HPV was determined by the polymerase chain reaction with MY9/11 L1 and GP5+/GP6+ L1 primers, followed by restriction fragment length polymorphism and reverse line blotting hybridization, respectively. In total, 12 high-risk and 24 low-risk HPVs types were detected. HPV 16 was the most prevalent, followed by HPV 18 in cervical cancer (14.6%), HPV 31 in high-grade squamous intraepithelial lesions (14.9%), HPVs 58/42 in low-grade squamous intraepithelial lesions (9.1% each), and HPVs 31/58 (2.4% each) in women without squamous intraepithelial lesions. Among 285 positive samples, 24.2% harbored multiple HPV types, being this more prevalent in women with squamous intraepithelial lesions (30.8% in low-grade squamous intraepithelial lesions, 22.5% in high-grade squamous intraepithelial lesions, and 22.0% in cervical cancer) than in women without lesions (9.3%). The higher prevalence of HPV 16 and other high-risk HPVs in women both with and without cervical lesions may explain the high incidence of cervical cancer in Paraguay. This information may be of importance for local decision makers to improve prevention strategies. In addition, these results may be useful as baseline pre-vaccination data for a future virological surveillance in Paraguay.

[Prevalence of cervical infection by human papilloma virus (HPV) in the Caucasian and Guaraní populations residing in the province of Misiones, Argentina]. / Prevalencia de la infección cervical por virus papiloma humano (HPV) en población caucásica y guaraní, residente en la provincia de Misiones, Argentina.

A genital infection with human papillomavirus (HPV) of a high risk type is necessary for the development of cervical carcinoma. HPV viral distribution among diverse world populations is not homogeneous, viral reservoirs having been detected in particular regions that can interact when humans engage in active contacts. Such viral dynamics alters the population cervical cancer relative risk, particularly when the prevalence of HPV oncogenic risk types is high. We have compared women exposed to different social, cultural and environmental conditions regarding cervical HPV infection, analyzing two populations from Misiones, Argentina: White urban women and--Guarani indian women living in the rain forest. Demographic, clinical and sexual behavior data were collected and cytological, colposcopical and virological analysis performed. Detection and genotypification of HPV was performed by PCR-RFLP. The prevalence for generic HPV infection found was high in both populations, urban women: 43%, Guarani indians: 60%, with a statistically significant difference. These values were positively associated to age of first intercourse, number of male partners and smoking history. HPV type-specific prevalences showed a relative homogeneity between populations when the main representatives of the high risk (16 and 18: 23%) and low risk (6 y 11: 12%) types were grouped together. However, the presence of other viral types was notoriously different, representing only 9% in urban women and 29% in Guarani indians with particularly high risk HPV types (33, 35, 39, 45, 51, 52, 58, 67, 68). This situation might be of importance for future viral dynamics, phylogenetic and vaccine formulation studies.

Prevalencia de la infección cervical por virus papiloma humano (HPV) en población caucásica y guaraní, residente en la provincia de Misiones, Argentina / [Prevalence of cervical infection by human papilloma virus (HPV) in the Caucasian and Guaraní populations residing in the province of Misiones, Argentina]

A genital infection with human papillomavirus (HPV) of a high risk type is necessary for the development of cervical carcinoma. HPV viral distribution among diverse world populations is not homogeneous, viral reservoirs having been detected in particular regions that can interact when humans engage in active contacts. Such viral dynamics alters the population cervical cancer relative risk, particularly when the prevalence of HPV oncogenic risk types is high. We have compared women exposed to different social, cultural and environmental conditions regarding cervical HPV infection, analyzing two populations from Misiones, Argentina: White urban women and--Guarani indian women living in the rain forest. Demographic, clinical and sexual behavior data were collected and cytological, colposcopical and virological analysis performed. Detection and genotypification of HPV was performed by PCR-RFLP. The prevalence for generic HPV infection found was high in both populations, urban women: 43

, with a statistically significant difference. These values were positively associated to age of first intercourse, number of male partners and smoking history. HPV type-specific prevalences showed a relative homogeneity between populations when the main representatives of the high risk (16 and 18: 23

) types were grouped together. However, the presence of other viral types was notoriously different, representing only 9

in urban women and 29

in Guarani indians with particularly high risk HPV types (33, 35, 39, 45, 51, 52, 58, 67, 68). This situation might be of importance for future viral dynamics, phylogenetic and vaccine formulation studies.

) and low risk (6 y 11: 12

Prevalencia de la infección cervical por virus papiloma humano (HPV) en población caucásica y guaraní, residente en la provincia de Misiones, Argentina. / [Prevalence of cervical infection by human papilloma virus (HPV) in the Caucasian and Guaraní populations residing in the province of Misiones, Argentina]

A genital infection with human papillomavirus (HPV) of a high risk type is necessary for the development of cervical carcinoma. HPV viral distribution among diverse world populations is not homogeneous, viral reservoirs having been detected in particular regions that can interact when humans engage in active contacts. Such viral dynamics alters the population cervical cancer relative risk, particularly when the prevalence of HPV oncogenic risk types is high. We have compared women exposed to different social, cultural and environmental conditions regarding cervical HPV infection, analyzing two populations from Misiones, Argentina: White urban women and--Guarani indian women living in the rain forest. Demographic, clinical and sexual behavior data were collected and cytological, colposcopical and virological analysis performed. Detection and genotypification of HPV was performed by PCR-RFLP. The prevalence for generic HPV infection found was high in both populations, urban women: 43

, Guarani indians: 60

, with a statistically significant difference. These values were positively associated to age of first intercourse, number of male partners and smoking history. HPV type-specific prevalences showed a relative homogeneity between populations when the main representatives of the high risk (16 and 18: 23

) and low risk (6 y 11: 12

) types were grouped together. However, the presence of other viral types was notoriously different, representing only 9

in urban women and 29

in Guarani indians with particularly high risk HPV types (33, 35, 39, 45, 51, 52, 58, 67, 68). This situation might be of importance for future viral dynamics, phylogenetic and vaccine formulation studies.