Male patient 54-year-old presented with constipation and a complaint of anal stenosis. The condition started about 30 years ago with a perianal abscess, the patient sought medical advice and surgical treatment of the abscess was done. One year later, the patient presented with anal pain, fever, and bleeding per rectum and was diagnosed with piles. Medical treatment, including antibiotics, was given. The patient clinical condition was improved. Three years later, there was a similar attack of fever, anal pain, and bleeding. This time the patient was diagnosed with anal stenosis and anal dilation was done with post dilation bleeding, the patient was admitted to the hospital for blood transfusion.A biopsy was taken from anal canal during dilation and histopathological examination revealed nonspecific inflammation. One year ago, there was constipation, straining during defecation. Computed tomography was done that revealed mild rectal wall thickening. Barium enema with double contrast was normal. Colonoscopy till hepatic flexure revealed hyperemic rectal mucosa with sessile polyp where multiple biopsies were taken for histopathology that revealed inflammatory colonic polyp. Anal dilation was done again without improvement. Biopsies from two anal skin nodules were taken during dilation revealed epidermal cysts. One month ago, spiral CT of the abdomen and pelvis revealed mild dilatation of the colon and the rectum with mural thickening. Another colonoscopy was done that revealed multiple erosions in the colonic mucosa, more on the left side of the colon. Also, there were internal piles. Multiple biopsies were taken from the colonic erosions for histopathological examination. PR before the colonoscopy revealed that the anal canal is not straight, may be due to surgical procedures around the anal verge.
What is your diagnosis?