RESUMEN
INTRODUCTION: The incidence of intraepithelial anal neoplasia is increasing in certain risk behaviour groups, and human papillomavirus (HPV) infection is involved in its pathogenesis. The systematic use of anal cytology, and more recently HPV detection by hybrid capture and genotyping, have been introduced into screening programs in recent decades. MATERIAL AND METHODS: A retrospective cohort study was carried out on individuals with risk behaviours of developing intraepithelial anal neoplasia and who attended Sexually Transmitted Infections clinics in the Dermatology area of the Hospital Costa del Sol from January 2010 to December 2012. The intraepithelial anal neoplasia screening was performed using anal cytology and HPV genotyping. RESULTS: Half (50%) of the study population were HIV positive. A high frequency of anal dysplasia and presence of HPV in cytology (82.1%) and genotype (79%) was found. A statistically significant association (P<.005) was obtained between the presence of high-risk HPV genotypes and the presence of high-grade dysplasia in the second directed cytology. HPV genotyping enabled 17 cases (22%) of severe dysplasia to be identified that were under-diagnosed in the first cytology. CONCLUSION: Cases of high-grade dysplasia can be under-diagnosed by a first anal cytology. Detection of HPV can supplement this procedure, leading to the identification of those patients most at risk of developing high-grade anal dysplasia.