Is there a higher frequency of anal dysplasia and infection by human papillomavirus in Crohn's disease patients?

The aim of this study was to compare the frequency of dysplasia and human papillomavirus (HPV) infection in the anal canal of patients with Crohn's disease (CD) with a control group and assess whether there is a correlation between use of immunosuppressants and anal manifestation of CD. Patients with CD and control individuals were submitted to anal cytology and material collection for polymerase chain reaction (PCR). The cytology was classified as normal, atypical squamous cells of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (LSIL), or high-grade (HSIL). PCR was considered positive or negative according to virus presence or absence. A total of 117 patients were included (54 in the control group and 63 in the CD group, being 32 without and 31 with immunosuppressants). ASCUS and LSIL were found in 25.9 and 22.2% of control patients and 28.6 and 39.7% of CD patients. HPV was identified in 14.8% of the control group and 27% of the CD group. In CD patients, HPV was found in 37.5 and 16.1% of those without and with immunosuppressants, respectively. Patients with perianal involvement had 15.6% of PCR positivity. There was no statistical difference in dysplasia and infection by HPV between the groups. Use of immunosuppressants did not influence the result, but anal manifestation was inversely proportional to viral detection.