title: Prevalence of Anal Dysplasia in Patients With Inflammatory Bowel Disease.
abstract: OBJECTIVE
  Although the prevalence of anal dysplasia is higher in some immunosuppressed populations, the prevalence in patients with inflammatory bowel disease (IBD) is unknown. We examined the prevalence of abnormal anal cytology among IBD patients, and its relation to the human papilloma virus (HPV).
  
  
  METHODS
  Adults with IBD and age-matched healthy controls (HC) were recruited. IBD patients were categorized as nonimmunosuppressed (IBD-N) or immunosuppressed (IBD-I). Anal Papanicolaou tests were performed for HPV testing and classification by a cytopathologist as follows: negative, atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesion, high-grade squamous intraepithelial lesion, cancer, or unsatisfactory.
  
  
  RESULTS
  A total of 270 subjects (100 IBD-I, 94 IBD-N, and 76 HC) were recruited. ASC-US were detected in 19 subjects, with a trend toward a higher prevalence among IBD subjects compared with HC (8.8% vs 2.6%; P = .10). The prevalence did not differ with respect to immunosuppression. Crohn's disease (CD) subjects had a higher prevalence of ASC-US compared with others with IBD (P = .02). Among those with CD, female sex and disease duration longer than 10 years were risk factors. There were no cases of low-grade squamous intraepithelial lesion, high-grade squamous intraepithelial lesion, or anal cancer in the cohort. HPV was present in 5.3% and 1.5% of subjects with and without ASC-US, respectively (P = .26).
  
  
  CONCLUSIONS
  Although there was a trend toward abnormal anal Papanicolaou tests in IBD subjects compared with HC, there was no difference based on immunosuppression. The presence of HPV did not correlate with abnormal anal cytology. Risk factors associated with this increased trend include female CD subjects and those with a longer duration of CD. ClinicalTrials.gov number: NCT01860963; https://clinicaltrials.gov/ct2/show/NCT01860963.
authors.affiliation: Division of Gastroenterology, Stanford University School of Medicine, Stanford, California. Electronic address: shamita.shah@stanford.edu.
authors.forename: Shamita B
authors.initials: SB
authors.lastname: Shah
authors.affiliation: Division of Colorectal Surgery, Stanford University School of Medicine, Stanford, California.
authors.forename: Danielle
authors.initials: D
authors.lastname: Pickham
authors.affiliation: Division of Gastroenterology, Stanford University School of Medicine, Stanford, California.
authors.forename: Hiwot
authors.initials: H
authors.lastname: Araya
authors.affiliation: Division of Gastroenterology, Santa Clara Valley Medical Center, San Jose, California.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Kamal
authors.affiliation: Division of Colorectal Surgery, Stanford University School of Medicine, Stanford, California.
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Pineda
authors.affiliation: Division of Colorectal Surgery, Stanford University School of Medicine, Stanford, California.
authors.forename: Saif
authors.initials: S
authors.lastname: Ghole
authors.affiliation: Division of Colorectal Surgery, Stanford University School of Medicine, Stanford, California.
authors.forename: Lauren
authors.initials: L
authors.lastname: Shih
authors.affiliation: Department of Pathology, Stanford University School of Medicine, Stanford, California.
authors.forename: Christina
authors.initials: C
authors.lastname: Kong
authors.affiliation: Department of Pathology, Stanford University School of Medicine, Stanford, California.
authors.forename: Reet
authors.initials: R
authors.lastname: Pai
authors.affiliation: Surgery-Colorectal Surgery, Stanford University School of Medicine, Stanford, California.
authors.forename: Mark
authors.initials: M
authors.lastname: Welton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001005:Anus Neoplasms / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications*; D008297:Male; D008875:Middle Aged; D065006:Papanicolaou Test; D027383:Papillomaviridae / Q000302:isolation & purification; D011230:Precancerous Conditions / Q000453:epidemiology*; D015995:Prevalence; D055815:Young Adult
keywords: Anal Cancer; Anal Dysplasia; Anal Pap Test; Atypical Squamous Cells of Undetermined Significance (ASC-US); Crohn's Disease; High-Grade Squamous Intraepithelial Lesion (HSIL); Human Papilloma Virus (HPV); Immunosuppression; Inflammatory Bowel Disease (IBD); Low-Grade Squamous Intraepithelial Lesion (LSIL); Ulcerative Colitis