title: Anal dysplasia
text: # Anal dysplasia
  
  Anal dysplasia is a pre-cancerous condition which occurs when the lining of the anal canal undergoes abnormal changes. It can be classified as low grade squamous intraepithelial lesions (LSIL) and high-grade squamous intraepithelial lesions (HSIL). Most cases are not associated with symptoms, but people may notice lumps in and around the anus.
  
  ## Causes
  
  Anal dysplasia is most commonly linked to human papillomavirus (HPV), a usually sexually-transmitted infection. HPV is the most common sexually transmitted infection in the United States while genital herpes (HSV) was the most common sexually transmitted infection globally.
  
  